EP3143382A1 - Measuring apparatus and method for determining a substance concentration - Google Patents

Measuring apparatus and method for determining a substance concentration

Info

Publication number
EP3143382A1
EP3143382A1 EP15721588.0A EP15721588A EP3143382A1 EP 3143382 A1 EP3143382 A1 EP 3143382A1 EP 15721588 A EP15721588 A EP 15721588A EP 3143382 A1 EP3143382 A1 EP 3143382A1
Authority
EP
European Patent Office
Prior art keywords
measuring
wavelength
volume
measurement
fluorescence
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP15721588.0A
Other languages
German (de)
French (fr)
Inventor
Daniel Platte
Peter SCHROEREN
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
optek-Danulat GmbH
Optek Danulat GmbH
Original Assignee
optek-Danulat GmbH
Optek Danulat GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by optek-Danulat GmbH, Optek Danulat GmbH filed Critical optek-Danulat GmbH
Priority to EP23210847.2A priority Critical patent/EP4300079A3/en
Priority to EP20195394.0A priority patent/EP3770585B1/en
Publication of EP3143382A1 publication Critical patent/EP3143382A1/en
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/314—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry with comparison of measurements at specific and non-specific wavelengths
    • G01N2021/317—Special constructive features
    • G01N2021/3174—Filter wheel
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N2021/3185—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry typically monochromatic or band-limited
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/33—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using ultraviolet light

Definitions

  • the present invention relates to a measuring device for determining a substance concentration of a fluid arranged in a measuring volume according to claim 1 and a corresponding method according to claim 9.
  • Measuring accuracy in the largest possible concentration range of the substance to be measured important. It is equally important that the measurement accuracy is maintained over a long measuring period, so that calibration of the measuring device is as rare as possible, if at all unnecessary.
  • the latter is used, for example, in the chromatographic separation of protein solutions.
  • the absorption measurement controls a selection with regard to concentration and / or impurities based on the measurement results.
  • a replacement substance can be used for the purpose of device calibration. This is particularly advantageous if the substance to be measured is expensive, has a poor resistance or this is generally difficult to handle.
  • the object of the present invention is therefore to provide a measuring device and a method for determining a substance concentration, which allow the most accurate and long-term reproducible measurement.
  • the invention is based on the idea to minimize unwanted effects of a source spectrum on the measurement / determination of the substance concentration. This is done according to the invention in particular by arranging a fluorescence-reducing element in the beam path, preferably between the detector and the measuring volume and limiting the
  • Irradiation into the measuring volume in particular of the radiation having a wavelength deviating from the measuring wavelength, preferably short-wave radiation.
  • Measuring wavelength or measuring wavelength range are used below as alternative names, but should each relate to both.
  • the spectrum which arrives at a detector without influencing a substance to be measured in the measurement volume is regarded as the measurement spectrum.
  • an optical determination in particular with an electromagnetic radiation in the measuring wavelength range between 1 nm and 5 ⁇ m, is preferred.
  • the (decadic) logarithm of the quotient of transmitted (Lt) and irradiated (L0) light power at a given layer thickness D at each wavelength is proportional to the substance concentration c (in particular particle number per volume, for example mol / l) :
  • the proportionality constant k will be called the absorption coefficient below.
  • the relationship shown in the above equation applies to almost all substances over a wide concentration range.
  • the transmitted light have the same wavelength and no scattering of the light takes place in the measuring volume.
  • the practical measurement of A presupposes that the total optical radiation covers an approximately equal distance in the measuring volume. It is therefore preferred according to the invention if the measurement volume in the beam path direction is limited by plane-parallel windows and / or a measurement beam emitted by a measurement source runs approximately parallel, ie in particular non-scattering.
  • the present invention is based in particular on the knowledge that with substances contained in the fluid to be measured
  • a broad fluorescence light is produced at a measuring wavelength of 280 nm with a maximum at approximately 350 nm.
  • Attenuation of the light at the measurement length by more than two Orders of magnitude. Furthermore, the fluorescence yield depends on the temperature and environment of the molecule and can be disturbed by other substances. Deviations from the linearity of the measurement result at different concentrations, so that the measurement results are less reproducible and scalable.
  • the core of the present invention is therefore in particular the measurement of the spectral absorption for the determination of a substance concentration, wherein in the beam path both before and after the measurement volume
  • wavelength selective means / components are arranged.
  • wavelength-selective means / components are characterized in particular by the fact that radiation from the source spectrum in undesired wavelength ranges, ie in particular outside the measurement wavelength, is reduced more strongly than in the desired one
  • wavelength-selective means are arranged, through which harmful
  • Radiation of the source spectrum in particular in a short wavelength with respect to the measurement wavelength range, is reduced.
  • the fluid arranged in the measuring volume is loaded as little as possible with radiation.
  • the wave length-selective means arranged behind the measurement volume can in particular be a fluorescence-reducing element.
  • the fluorescence-reducing element is preferably an interference filter with more than 10% transmission, in particular more than 20% transmission, preferably more than 30% transmission
  • the source spectrum becomes the measurement wavelength
  • the further wavelength-selective means / components can be formed, in particular, by forming the source as a narrow-band light source and / or an additional filter, which is preferably arranged downstream of the measurement volume and arranged in the beam path.
  • the spectral distribution of the measuring radiation is preferably determined essentially by the wavelength-selective means arranged in front of the measuring volume, in particular a monochromator having a measuring wavelength of 280 nm and a maximum half-value width of 5 nm.
  • the intensity of the measuring radiation is reduced by at most a factor of 10, preferably at most a factor of 5, by the wavelength-selective means arranged after the measuring volume.
  • the fluorescent light is preferably at least a factor of 20, preferably reduced by at least a factor of 50, more preferably at least a factor of 100.
  • An inventively preferred wavelength-selective means for wavelength selection before the measurement volume is a, in particular a narrow-band source spectrum emitting source.
  • the wave selection can be done by providing a narrow band light source,
  • the source may comprise a broadband light source with a downstream wavelength-selective intermediate element, in particular one of the following:
  • optical elements are in particular discretely constructed one behind the other. It is alternative or additionally conceivable, in particular, to effect a spatial separation and the optical radiation (source spectrum) between individual
  • the measuring device for determining the absorption is normalized or normalized to the intensity irradiated into the measuring volume. It is done in particular by the measuring volume with a not
  • absorbing reference fluid is filled to one or more
  • the wavelength-selective component connected downstream according to the invention is preferably a fluorescence-reducing element.
  • a filter is used which significantly less influences the measurement wavelength to be measured by the detector than compared to the measurement wavelength
  • the fluorescence-reducing element preferably has an absorption of less than 50%, more preferably less than 20%, at the measurement wavelength. In contrast, the fluorescence-reducing element has in the wavelength range in which a
  • Fluorescence emission would stimulate the highest possible absorption.
  • Beam path limiting component formed.
  • the fluorescence-reducing element in particular with a radiation-direction-selective element,
  • fluorescent radiation is at least predominantly reduced via the utilization of the different angular distribution, while the radiation to be measured at least predominantly passes through the fluorescence-reducing element and can be measured without the measurement at the detector
  • Fluorescence radiation is significantly affected. This can be
  • the detector for measuring the wavelength-related absorption of the source spectrum output by the source and passing through the measurement volume converts the measurement spectrum impinging on the detector into a photocurrent by means of an electrical current measurement.
  • a photomultiplier in particular a photomultiplier, a photodiode semiconductor and / or a vacuum tube used.
  • bolometric methods are conceivable since a wavelength-selected measurement spectrum impinges on the measuring wavelength on the detector.
  • a bolometer can be used as the detector.
  • the wavelength considered to be the measurement wavelength which at arithmetic averaging of, preferably weighted with the respective radiation intensity, at wavelength
  • the measuring wavelength lies in particular between 2 ⁇ nm and 1 ⁇ m, preferably between 250nm and 320nm, more preferably at 280nm +/- 5nm and / or 260nm +/- 5nm and / or 254nm +/- 5nm, more preferably at 280nm +/- 0, 1 nm.
  • the half-value width is, in particular, the distance, measured in wavelength, between the points in the intensity spectrum
  • the half-width in accordance with the invention is in particular at most 1/5 of the measuring wavelength, preferably at most 1/1 of the measuring wavelength, more preferably at most 1/50 of the measuring wavelength.
  • the thousandth of the width of the measuring radiation according to the invention is, in particular, the distance measured between the points in FIG.
  • the millisecond is according to the invention in particular a maximum of half the measuring wavelength, preferably a maximum of a quarter of
  • means for reducing shortwave and / or longwave radiation with respect to the measurement wavelength are at least a factor of 2, preferably at least a factor of 10, more preferably at least a factor of 100, based on the irradiated power density
  • Measuring wavelength provided before entering the measuring volume a wavelength selection takes place between the measurement volume and the detector, the source spectrum being limited, in particular at least long-wave to the measurement wavelength, preferably with a decrease of at least a factor of 2, preferably at least a factor of 10, more preferably at least a factor of 1 00 to the measuring wavelength.
  • the waste occurs in particular in an environment around the measuring wavelength, which is in particular 50/100, preferably 2/100.
  • Figure 1 is a schematic, perspective view of a first
  • Figure 2 is a schematic, perspective view of a second
  • Embodiment of the measuring device according to the invention Embodiment of the measuring device according to the invention.
  • FIG. 1 shows a source 1 which is formed from a light source 2 and a wavelength-selective optical element 3.
  • Light source 2 is designed as a broadband light source, a
  • broadband source spectrum outputs with a beam path 7, which extends, in particular linear, up to a detector 6.
  • the broadband source spectrum of the light source 2 strikes the wavelength-selective optical element 3 and, when passing through the wavelength-selective optical element 3, radiation power is significantly reduced in the short-wave to a measurement wavelength of 280 nm.
  • the wavelength-selective element 3 leaves a narrowband
  • the narrowband source spectrum delimited at least below the measuring wavelength strikes a measuring volume 4 along the beam path 7.
  • the measuring volume 4 is bounded by a measuring space which has windows 8, 8 'arranged transversely to the beam path 7 at least in the direction of the beam path 7.
  • Beam path 7 arranged and preferably have a defined distance along the beam path 7. The distance corresponds to the layer thickness through which the narrow-band spectrum passes along the beam path 7 through a fluid arranged in the measurement volume.
  • the fluid is arranged either in the measuring volume 4 static or transverse to the beam path 7.
  • the fluid has a substance concentration to be determined of a substance (target substance), preferably tryptophan, which causes a measurable change by the detector 6 at the passing through the measurement volume 4 narrow-band source spectrum in the measurement wavelength range.
  • a substance target substance
  • tryptophan preferably tryptophan
  • the narrow-banded source spectrum can cause a fluorescence, in particular caused by the target substance, in the measuring volume 4, which fluoresces, inter alia, along the beam path 7 to a falsification of
  • the detector 6 can carry signals to be measured, in particular in a spectrum having a wavelength above the measuring wavelength.
  • Fluorescence radiation at least predominantly, preferably largely, more preferably fully absorbed.
  • the narrow-band spectrum provided for the measurement of the substance concentration, in particular short-wave and long-wave limited, meets the detector 6, which has its power density at least predominantly in the measurement length range.
  • the measuring spectrum preferably has a maximum of the power density at the measuring wavelength.
  • the fluorescence reducing element 5 is preferably selective at 280nm +/- 5nm and / or 260nm +/- 5nm and / or 254nm +/- 5nm.
  • the detector 6 measures this from the measuring volume 4 and through the
  • fluorescence-reducing element 5 passed light by conversion into a photocurrent via an electrical current measurement, in particular a photomultiplier. From this, it is possible to deduce the substance concentration of the target substance.
  • FIG. 2 differs from the embodiment described in FIG. 1 in that a narrow-band light source 2 'is provided as the source 1, so that a light source 2' is provided
  • the wavelength-selective optical element 3 can be omitted in this embodiment.
  • the light source 2 ' is already at least one predominantly in the measuring wavelength range radiant source spectrum and thus includes the front of the measuring volume 4 arranged
  • the fluorescence-reducing element 5 ' is preferably at least predominantly, preferably almost exclusively boring, selective to the measuring wavelength.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)

Abstract

The present invention relates to a measuring apparatus for determining a substance concentration in a fluid arranged in a measurement volume (4), having: – a source (1) that outputs a source spectrum, – a wavelength-selective means arranged before the measurement volume, – a measurement chamber that delimits the measurement volume (4) at least in a beam path (7), and – a detector (6) for measuring a wavelength-related absorption of a measurement spectrum that has passed through the measurement volume (4), wherein a fluorescence-reducing element (5) is arranged in the beam path (7) between the detector (6) and the measurement volume (4). The present invention also relates to a corresponding method.

Description

Messvorrichtung und Verfahren zur Bestimmung einer Stoffkonzentration  Measuring device and method for determining a substance concentration

B e s c h r e i b u n g Description

Die vorliegende Erfindung betrifft eine Messvorrichtung zur Bestimmung einer Stoffkonzentration eines in einem Messvolumen angeordneten Fluids gemäß Anspruch 1 und ein korrespondierendes Verfahren gemäß Anspruch 9. The present invention relates to a measuring device for determining a substance concentration of a fluid arranged in a measuring volume according to claim 1 and a corresponding method according to claim 9.

Bei der Prozesssteuerung sowie in der Qualitätssicherung von Produkten spielen gattungsgemäße Messvorrichtungen und Verfahren sowohl im In the process control as well as in the quality assurance of products, generic measuring devices and methods both in the

Labor- als auch im Prozessmaßstab eine große Rolle. Dabei ist die Laboratory as well as on a process scale a big role. It is the

Messgenauigkeit in einem möglichst großen Konzentrationsbereich des zu messenden Stoffes wichtig. Eine ebenso große Rolle spielt es, dass die Messgenauigkeit über einen langen Messzeitraum aufrechterhalten bleibt, so dass eine Kalibrierung der Messvorrichtung möglichst selten bis gar nicht erforderlich ist. Measuring accuracy in the largest possible concentration range of the substance to be measured important. It is equally important that the measurement accuracy is maintained over a long measuring period, so that calibration of the measuring device is as rare as possible, if at all unnecessary.

In der Biotechnologie finden Absorptionsmessungen vor allem zur In biotechnology, absorption measurements are mainly used

Bestimmung der Konzentration von Nukleinsäuren sowie zur Bestimmung der Proteinkonzentration oder der Konzentration von Aminosäuren Determination of the concentration of nucleic acids as well as for the determination of the protein concentration or the concentration of amino acids

Anwendung. Letztere kommt beispielsweise bei der chromatographischen Trennung von Proteinlösungen zum Einsatz. Dabei entstehen insbesondere Produktströme, in welchen die zu bestimmende Substanz zu Application. The latter is used, for example, in the chromatographic separation of protein solutions. In particular, arise Product streams in which the substance to be determined to

unterschiedlichen Zeiten in unterschiedlicher Konzentration enthalten ist. Durch die Absorptionsmessung wird beispielsweise eine Selektion im Hinblick auf Konzentration und/oder Verunreinigungen aufgrund der Messergebnisse gesteuert. different times in different concentration is included. The absorption measurement, for example, controls a selection with regard to concentration and / or impurities based on the measurement results.

Für die Messvorrichtung, in der Regel ein Prozessphotometer, wird daher ein möglichst dynamischer und breiter Messbereich gefordert. Außerdem werden eine gute Reproduzierbarkeit der Messungen sowie eine gute For the measuring device, usually a process photometer, a dynamic and wide measuring range is therefore required. In addition, a good reproducibility of the measurements as well as a good

Vergleichbarkeit unterschiedlicher Messstellen bevorzugt. Um Comparability of different measuring points preferred. Around

aussagefähige Messergebnisse zu erlangen, deren Fehlerabschätzungen möglichst schmale Toleranzbänder ergeben, sind neben der guten to obtain meaningful measurement results whose error estimates give as narrow tolerance bands as possible, in addition to the good ones

Reproduzierbarkeit und Unabhängigkeit von Störeinflüssen auch eine gute Vergleichbarkeit der Messungen im Prozess mit denen im Labormaßstab sowie insbesondere eine gute Linearität zwischen der Stoffkonzentration und der Absorption gewünscht. Reproducibility and independence of interference also desired a good comparability of the measurements in the process with those on a laboratory scale and in particular a good linearity between the substance concentration and the absorption desired.

Ebenso ist es von Vorteil, wenn statt der eigentlich zu messenden Substanz für die Zwecke der Gerätekalibrierung eine Ersatzsubstanz eingesetzt werden kann. Dies ist besonders dann von Vorteil, wenn die zu vermessende Substanz teuer ist, eine schlechte Beständigkeit aufweist oder diese allgemein schlecht handhabbar ist. Likewise, it is advantageous if, instead of the substance actually to be measured, a replacement substance can be used for the purpose of device calibration. This is particularly advantageous if the substance to be measured is expensive, has a poor resistance or this is generally difficult to handle.

Aufgabe der vorliegenden Erfindung ist es daher, eine Messvorrichtung und ein Verfahren zur Bestimmung einer Stoffkonzentration anzugeben, die eine möglichst genaue und langfristig reproduzierbare Messung ermöglichen. The object of the present invention is therefore to provide a measuring device and a method for determining a substance concentration, which allow the most accurate and long-term reproducible measurement.

Die vorgenannten technischen Probleme werden insbesondere mit einer Messvorrichtung gemäß Anspruch 1 und/oder einem Verfahren gemäß Anspruch 9 gelöst. Vorteilhafte Weiterbildungen der Erfindung sind in den Unteransprüchen angegeben. In den Rahmen der Erfindung fallen auch sämtliche Kombinationen aus zumindest zwei von in der Beschreibung, den Ansprüchen und/oder den Figuren angegebenen Merkmalen. Bei The aforementioned technical problems are solved in particular with a measuring device according to claim 1 and / or a method according to claim 9. Advantageous developments of the invention are specified in the subclaims. Within the scope of the invention also fall all combinations of at least two features specified in the description, the claims and / or the figures. at

angegebenen Wertebereichen sollen auch innerhalb der genannten Grenzen liegende Werte als Grenzwerte offenbart und in beliebiger Kombination beanspruchbar sein. specified ranges of values are also within the limits mentioned limits as limits and be claimed in any combination claimable.

Der Erfindung liegt der Gedanke zugrunde, unerwünschte Einflüsse eines Quellspektrums auf die Messung/Bestimmung der Stoffkonzentration zu minimieren. Dies erfolgt erfindungsgemäß insbesondere durch Anordnung eines fluoreszenzreduzierenden Elements im Strahlengang, vorzugsweise zwischen dem Detektor und dem Messvolumen und Begrenzung der The invention is based on the idea to minimize unwanted effects of a source spectrum on the measurement / determination of the substance concentration. This is done according to the invention in particular by arranging a fluorescence-reducing element in the beam path, preferably between the detector and the measuring volume and limiting the

Einstrahlung in das Messvolumen, insbesondere der Strahlung mit zur Messwellenlänge abweichender Wellenlänge, vorzugsweise kurzwelligeren Strahlung. Die erfindungsgemäße Messvorrichtung und das Irradiation into the measuring volume, in particular of the radiation having a wavelength deviating from the measuring wavelength, preferably short-wave radiation. The measuring device according to the invention and the

erfindungsgemäße Verfahren werden daher bevorzugt bei Fluiden Processes according to the invention are therefore preferred for fluids

verwendet, die auf das, insbesondere schmalbandige, Quellspektrum und/oder die Messwellenlänge fluoreszierend ansprechen. used, which respond to the, in particular narrow-band, source spectrum and / or the measuring wavelength fluorescently.

Messwellenlänge oder Messwellenlängenbereich werden nachfolgend als alternative Bezeichnungen verwendet, sollen aber jeweils beides betreffen. Als Messspektrum wird erfindungsgemäß das Spektrum angesehen, das ohne Beeinflussung durch eine zu messende Substanz in dem Messvolumen an einem Detektor ankommt. Measuring wavelength or measuring wavelength range are used below as alternative names, but should each relate to both. According to the invention, the spectrum which arrives at a detector without influencing a substance to be measured in the measurement volume is regarded as the measurement spectrum.

Erfindungsgemäß bevorzugt wird eine optische Bestimmung, insbesondere mit einer elektromagnetischen Strahlung im Messwellenlängenbereich zwischen l OOnm und 5 μιη. Entsprechend dem Lambert-Beerschen Gesetz ist der (dekadische) Logarithmus des Quotienten aus transmittierter (Lt) und eingestrahlter (L0) Lichtleistung bei einer gegebenen Schichtdicke D bei j eder Wellenlänge proportional zu der Stoffkonzentration c (insbesondere Teilchenzahl pro Volumen, beispielsweise mol/I): A (Lamda) = logl O (LO/Lt) = k* c* D According to the invention, an optical determination, in particular with an electromagnetic radiation in the measuring wavelength range between 1 nm and 5 μm, is preferred. According to the Lambert-Beer law, the (decadic) logarithm of the quotient of transmitted (Lt) and irradiated (L0) light power at a given layer thickness D at each wavelength is proportional to the substance concentration c (in particular particle number per volume, for example mol / l) : A (lambda) = logl O (LO / Lt) = k * c * D

Die Proportionalitätskonstante k wird nachfolgend Absorptionskoeffizient genannt. Der in obiger Gleichung dargestellte Zusammenhang gilt für fast alle Substanzen über einen breiten Konzentrationsbereich. Durch die The proportionality constant k will be called the absorption coefficient below. The relationship shown in the above equation applies to almost all substances over a wide concentration range. By the

Verwendung der logarithmisch skalierten Verhältniszahl A ergibt sich ein linearer Zusammenhang zwischen dieser Größe und dem stoffabhängigen Absorptionskoeffizienten k, der Stoffkonzentration c und der Schichtdicke D. Der Zusammenhang gilt insbesondere, wenn eingestrahltes und Using the logarithmically scaled ratio A results in a linear relationship between this size and the substance-dependent absorption coefficient k, the substance concentration c and the layer thickness D. The relationship applies in particular when irradiated and

transmittiertes Licht die gleiche Wellenlänge haben und keine Streuung des Lichts im Messvolumen stattfindet. Die praktische Messung von A setzt voraus, dass die gesamte optische Strahlung eine annähernd gleiche Strecke im Messvolumen zurücklegt. Es ist daher erfindungsgemäß bevorzugt, wenn das Messvolumen in Strahlengangrichtung von planparallelen Fenstern begrenzt wird und/oder ein von einer Messquelle ausgegebener Messstrahl näherungsweise parallel verläuft, also insbesondere nicht streuend. transmitted light have the same wavelength and no scattering of the light takes place in the measuring volume. The practical measurement of A presupposes that the total optical radiation covers an approximately equal distance in the measuring volume. It is therefore preferred according to the invention if the measurement volume in the beam path direction is limited by plane-parallel windows and / or a measurement beam emitted by a measurement source runs approximately parallel, ie in particular non-scattering.

Der vorliegenden Erfindung liegt insbesondere die Erkenntnis zugrunde, dass sich bei in dem zu messenden Fluid enthaltenden Stoffen mit The present invention is based in particular on the knowledge that with substances contained in the fluid to be measured

fluoreszierenden Eigenschaften, insbesondere sich zeitli ch ändernde, Störeinflüsse auf das Messspektrum ergeben. Bei einer erfindungsgemäß bevorzugten Bestimmung einer Stoffkonzentration von Tryptophan enthaltenden Proteinen entsteht bei einer Messwellenlänge von 280nm ein ausgedehntes Fluoreszenzlicht mit einem Maximum bei circa 350nm. fluorescent properties, in particular zeitli ch changing, interference on the measurement spectrum result. In a preferred determination according to the invention of a substance concentration of tryptophan-containing proteins, a broad fluorescence light is produced at a measuring wavelength of 280 nm with a maximum at approximately 350 nm.

Hierdurch kann es zu Störungen bei der Detektion und dadurch zu This can lead to disturbances in the detection and thereby

Störungen bei der Bestimmung der Stoffkonzentration kommen. Disruptions in the determination of the substance concentration come.

Der beschriebene Effekt wird vor allem bei hohen Konzentrationen und/oder größeren Schichtdicken stärker bemerkbar, insbesondere bei einer The effect described becomes more noticeable, especially at high concentrations and / or greater layer thicknesses, especially in the case of one

Schwächung des Lichts bei der Messweilenlänge um mehr als zwei Größenordnungen. Weiterhin hängt die Fluoreszenzausbeute von der Temperatur und Umgebung des Moleküls ab und kann durch andere Stoffe gestört werden. Bei unterschiedlichen Konzentrationen ergeben sich daher Abweichungen von der Linearität der Messung, so dass die Messergebnisse weniger reproduzierbar und skalierbar sind. Attenuation of the light at the measurement length by more than two Orders of magnitude. Furthermore, the fluorescence yield depends on the temperature and environment of the molecule and can be disturbed by other substances. Deviations from the linearity of the measurement result at different concentrations, so that the measurement results are less reproducible and scalable.

Kern der vorliegenden Erfindung ist daher insbesondere die Messung der spektralen Absorption zur Bestimmung einer Stoffkonzentration, wobei im Strahlengang sowohl vor als auch nach dem Messvolumen The core of the present invention is therefore in particular the measurement of the spectral absorption for the determination of a substance concentration, wherein in the beam path both before and after the measurement volume

wellenlängenselektive Mittel/Bauteile angeordnet sind. wavelength selective means / components are arranged.

Wellenlängenselektive Mittel/Bauteile zeichnen sich erfindungsgemäß insbesondere dadurch aus, dass durch sie Strahlung des Quellspektrums in unerwünschten Weüenlängenbereichen, also insbesondere außerhalb der Messwellenlänge, stärker reduziert wird als in dem erwünschten According to the invention, wavelength-selective means / components are characterized in particular by the fact that radiation from the source spectrum in undesired wavelength ranges, ie in particular outside the measurement wavelength, is reduced more strongly than in the desired one

Wellenlängenbereich. Wavelength range.

Auf der Einstrahlungsseite, also im Strahlengang vor dem Messvolumen, sind wellenlängenselektive Mittel angeordnet, durch die schädliche On the irradiation side, ie in the beam path in front of the measurement volume, wavelength-selective means are arranged, through which harmful

Strahlung des Quellspektrums, insbesondere in einem gegenüber der Messwellenlänge kurzwelligen Bereich, reduziert wird. Durch diese erfindungsgemäße Maßnahme wird das im Messvolumen angeordnete Fluid möglichst wenig mit Strahlung belastet. Radiation of the source spectrum, in particular in a short wavelength with respect to the measurement wavelength range, is reduced. By means of this measure according to the invention, the fluid arranged in the measuring volume is loaded as little as possible with radiation.

Durch die nach dem Messvolumen in dem Strahlengang angeordneten wellenlängenselektiven Mittel wird, insbesondere durch die Due to the wavelength-selective means arranged in the beam path after the measurement volume, in particular by the

Messwellenlänge im Messvolumen angeregtes, Fluoreszenzlicht Measuring wavelength in the measuring volume excited, fluorescent light

reduziert/absorbiert, um eine lineare und reproduzierbare Messung über einen breiten Stoffkonzentrationsbereich sicherzustellen. Das hinter dem Messvolumen angeordnete welleniängenselektive Mittel kann insbesondere ein fluoreszenzreduzierendes Element sein. Bei dem fluoreszenzreduzierenden Element handelt es sich vorzugsweise um einen Interferenzfilter mit mehr als 10% Transmission, insbesondere mehr als 20% Transmission, bevorzugt mehr als 30% Transmission, einer reduced / absorbed to ensure a linear and reproducible measurement over a wide range of substance concentration. The wave length-selective means arranged behind the measurement volume can in particular be a fluorescence-reducing element. The fluorescence-reducing element is preferably an interference filter with more than 10% transmission, in particular more than 20% transmission, preferably more than 30% transmission

Mittelwellenlänge von 280nm und einer Halbwertsbreite von maximal 40nm, bevorzugt maximal 20nm, noch bevorzugter zwischen 9 und 1 5nm. Central wavelength of 280 nm and a maximum width of half maximum of 40 nm, preferably at most 20 nm, more preferably between 9 and 1 5 nm.

Durch die vor und nach dem Messvolumen angeordneten By the arranged before and after the measuring volume

wellenlängenselektiven Mittel und/oder weitere wellenlängenselektive Mittel/Bauteile wird das Quellspektrum auf die Messwellenlänge wavelength-selective means and / or further wavelength-selective means / components, the source spectrum becomes the measurement wavelength

konzentriert, weist also bevorzugt bei der Messwellenlänge ein Maximum auf. Bevorzugt wird dabei eine Messwellenlänge, bei der die Absorption der zu messenden Stoffkonzentration des Stoffes möglichst hoch ist, concentrated, thus preferably has a maximum at the measurement wavelength. Preference is given to a measuring wavelength at which the absorption of the substance concentration of the substance to be measured is as high as possible,

insbesondere ein lokales Maximum aufweist. in particular has a local maximum.

Die weiteren wellenlängenselektiven Mittel/Bauteile können insbesondere durch Ausbildung der Quelle als schmalbandige Lichtquelle und/oder einen zusätzlichen, bevorzugt dem Messvolumen nachgelagerten, im Strahlengang angeordneten Filter, gebildet sein. The further wavelength-selective means / components can be formed, in particular, by forming the source as a narrow-band light source and / or an additional filter, which is preferably arranged downstream of the measurement volume and arranged in the beam path.

Bevorzugt wird die spektrale Verteilung der Messstrahlung im wesentlichen durch das vor dem Messvolumen angeordnete wellenlängenselektive Mittel, insbesondere einen Monochromator mit einer Messwellenlänge von 280nm und einer Halbwertsbreite von maximal 5nm, bestimmt. The spectral distribution of the measuring radiation is preferably determined essentially by the wavelength-selective means arranged in front of the measuring volume, in particular a monochromator having a measuring wavelength of 280 nm and a maximum half-value width of 5 nm.

Gemäß einer vorteilhaften Ausführungsform der vorliegenden Erfindung wird die Intensität der Messstrahlung durch das nach dem Messvolumen angeordnete wellenlängenselektive Mittel höchstens um einen Faktor 10, vorzugsweise höchstens um einen Faktor 5, reduziert. Das Fluoreszenzlicht wird dagegen bevorzugt mindestens um einen Faktor 20, vorzugsweise mindestens um einen Faktor 50, noch bevorzugter mindestens um einen Faktor 100 reduziert. According to an advantageous embodiment of the present invention, the intensity of the measuring radiation is reduced by at most a factor of 10, preferably at most a factor of 5, by the wavelength-selective means arranged after the measuring volume. In contrast, the fluorescent light is preferably at least a factor of 20, preferably reduced by at least a factor of 50, more preferably at least a factor of 100.

Ein erfindungsgemäß bevorzugtes wellenlängenselektives Mittel zur Wellenlängenselektion vor dem Messvolumen ist eine, insbesondere ein schmalbandiges Quellspektrum ausgebende, Quelle. Die Wellenselektion kann durch Vorsehen einer schmalbandigen Lichtquelle erfolgen, An inventively preferred wavelength-selective means for wavelength selection before the measurement volume is a, in particular a narrow-band source spectrum emitting source. The wave selection can be done by providing a narrow band light source,

insbesondere einer oder mehrerer der nachfolgend genannten Lichtquellen: in particular one or more of the following light sources:

- LEDs, - LEDs,

- Niederdruckgasentladungslampen,  Low pressure gas discharge lamps,

- Laser, vorzugsweise durchstimmbare.  - Laser, preferably tunable.

Alternativ kann die Quelle eine breitbandige Lichtquelle mit einem nachgeschalteten wellenlängenselektiven Zwischenelement aufweisen, insbesondere eines der folgenden: Alternatively, the source may comprise a broadband light source with a downstream wavelength-selective intermediate element, in particular one of the following:

- mindestens ein Beugungsgitter und/oder - At least one diffraction grating and / or

- mindestens einen Interferenzfilter.  - at least one interference filter.

Als breitbandige Quelle kommen erfindungsgemäß insbesondere folgende in Frage: As a broadband source according to the invention in particular the following are in question:

- Glühlampen, - Lightbulbs,

- Plasmaquellen,  Plasma sources,

- Gasentladungslampen.  - Gas discharge lamps.

Gemäß einer Ausführungsform der vorliegenden Erfindung ist es denkbar, eine Kombination von Linienquellen mit zusätzlichen According to one embodiment of the present invention, it is conceivable to provide a combination of line sources with additional ones

wellenlängenbestimmenden Elementen vorzusehen. Die optischen Elemente sind insbesondere diskret hintereinander aufgebaut. Es ist alternativ oder zusätzlich insbesondere denkbar, eine räumliche Trennung herbeizuführen und die optische Strahlung (Quellspektrum) zwischen einzelnen to provide wavelength-determining elements. The optical elements are in particular discretely constructed one behind the other. It is alternative or additionally conceivable, in particular, to effect a spatial separation and the optical radiation (source spectrum) between individual

Komponenten über Lichtleitelemente, insbesondere Lichtleitfasern, Components via light-conducting elements, in particular optical fibers,

Linsenleitungen und/oder Leitungen mit Gradientenindexlinsen, zu führen. Lens lines and / or lines with Gradientenindexlinsen to lead.

Gemäß einer weiteren vorteilhaften Ausführungsform der vorliegenden Erfindung ist die Messvorri chtung zur Bestimmung der Absorption auf die in das Messvolumen eingestrahlte Intensität normierbar oder normiert. Di es erfolgt insbesondere, indem das Messvolumen mit einem nicht According to a further advantageous embodiment of the present invention, the measuring device for determining the absorption is normalized or normalized to the intensity irradiated into the measuring volume. It is done in particular by the measuring volume with a not

absorbierenden Referenzfluid gefüllt wird, um einen oder mehrere absorbing reference fluid is filled to one or more

Referenzwert(e) für das Messspektrum aufzunehmen. Record reference value (s) for the measurement spectrum.

Gemäß einer weiteren, vorteilhaften Ausführungsform der Erfindung ist es denkbar, die eingestrahlte Intensität in zeitlichen Intervallen oder dauernd zu überwachen, um zeitliche Veränderungen der eingestrahlten Intensität berücksichtigen zu können. Dies kann insbesondere über ein Umleiten des Quellspektrums erfolgen, insbesondere über einen Chopperspiegel. According to a further advantageous embodiment of the invention, it is conceivable to monitor the irradiated intensity at time intervals or continuously in order to be able to take account of temporal changes in the irradiated intensity. This can be done in particular by redirecting the source spectrum, in particular via a chopper mirror.

Das erfindungsgemäß nachgeschaltete wellenlängenselektive Bauteil ist bevorzugt ein fluoreszenzreduzierendes Element. Bevorzugt wird ein Filter verwendet, welches die vom Detektor zu messende Messwellenlänge deutlich weniger beeinflusst als gegenüber der Messwellenlänge The wavelength-selective component connected downstream according to the invention is preferably a fluorescence-reducing element. Preferably, a filter is used which significantly less influences the measurement wavelength to be measured by the detector than compared to the measurement wavelength

langwelligere Strahlung. Das fluoreszenzreduzierende Element weist bei der Messwellenlänge bevorzugt eine Absorption von weniger als 50%, noch bevorzugter weniger als 20%, auf. Das fluoreszenzreduzierende Element weist dagegen in dem Wellenlängenbereich, in welchem eine long-wave radiation. The fluorescence-reducing element preferably has an absorption of less than 50%, more preferably less than 20%, at the measurement wavelength. In contrast, the fluorescence-reducing element has in the wavelength range in which a

Fluoreszenzemission angeregt würde, eine möglichst hohe Absorption auf. Erfindungsgemäß denkbar ist es außerdem, mehrere Messwellenlängen und mehrere Bereiche zur Fluoreszenzreduzierung und/oder ein Element mit durchstimmbarem Durchlassbereich im Strahlengang anzuordnen. Gemäß einer weiteren vorteilhaften Ausführungsform der Erfindung ist mindestens ein wellenlängenselektives Bauteil, insbesondere das Fluorescence emission would stimulate the highest possible absorption. According to the invention, it is also conceivable to arrange a plurality of measuring wavelengths and a plurality of regions for fluorescence reduction and / or an element with a tunable passband in the beam path. According to a further advantageous embodiment of the invention, at least one wavelength-selective component, in particular the

fluoreszenzreduzierende Element, als das Messvolumen entlang des fluorescence-reducing element, as the measuring volume along the

Strahlenganges begrenzendes Bauteil ausgebildet. Beam path limiting component formed.

Alternativ oder zusätzlich ist das fluoreszenzreduzierende Element, insbesondere mit einem strahlungsrichtungsselektiven Element, Alternatively or additionally, the fluorescence-reducing element, in particular with a radiation-direction-selective element,

ausgestattet. Hierdurch wird über die Ausnutzung der unterschiedlichen Winkelverteilung Fluoreszenzstrahlung zumindest überwiegend reduziert, während die zu messende Strahlung zumindest überwiegend durch das fluoreszenzreduzierende Element unverändert durchtritt und gemessen werden kann, ohne dass die Messung am Detektor durch fitted. As a result, fluorescent radiation is at least predominantly reduced via the utilization of the different angular distribution, while the radiation to be measured at least predominantly passes through the fluorescence-reducing element and can be measured without the measurement at the detector

Fluoreszenzstrahlung nennenswert beeinflusst wird. Dies kann Fluorescence radiation is significantly affected. This can

erfindungsgemäß insbesondere durch einen optischen Raumfilter gelöst werden. be solved according to the invention in particular by an optical spatial filter.

Gemäß einer bevorzugten Ausführungsform der vorliegenden Erfindung setzt der Detektor zur Messung der wellenlängenbezogenen Absorption des von der Quelle ausgegebenen und durch das Messvolumen getretenen Quellspektrums durch eine elektrische Strommessung das auf dem Detektor auftreffende Messspektrum in einen Fotostrom um. Hierzu wird In accordance with a preferred embodiment of the present invention, the detector for measuring the wavelength-related absorption of the source spectrum output by the source and passing through the measurement volume converts the measurement spectrum impinging on the detector into a photocurrent by means of an electrical current measurement. For this purpose is

insbesondere ein Photomultiplier, ein Photodiodenhalbleiter und/oder eine Vakuumröhre verwendet. Alternativ sind bolometrische Verfahren denkbar, da auf den Detektor ein auf die Messwellenlänge wellenlängenselektiertes Messspektrum auftrifft. Als Detektor kann insbesondere ein Bolometer verwendet werden. in particular a photomultiplier, a photodiode semiconductor and / or a vacuum tube used. Alternatively, bolometric methods are conceivable since a wavelength-selected measurement spectrum impinges on the measuring wavelength on the detector. In particular, a bolometer can be used as the detector.

Erfindungsgemäß wird als Messwellenlänge insbesondere die Wellenlänge betrachtet, die bei arithmetischer Mittelung der, vorzugsweise mit der jeweiligen Strahlungsintensität gewichteten, Wellenlänge bei According to the invention, the wavelength considered to be the measurement wavelength, which at arithmetic averaging of, preferably weighted with the respective radiation intensity, at wavelength

vernachlässigbarer Absorption einer Zielsubstanz (deren Stoffkonzentration gemessen wird) von einem Detektor, insbesondere ohne Möglichkeit der weiteren Wellenlängenselektion, registriert wird. negligible absorption of a target substance (its substance concentration measured) is registered by a detector, in particular without possibility of further wavelength selection.

Die Messwellenlänge liegt erfindungsgemäß insbesondere zwischen 2Ö0nm und 1 5 μηι, vorzugsweise zwischen 250nm und 320nm, noch bevorzugter bei 280nm +/- 5nm und/oder 260nm +/- 5nm und/oder 254nm +/- 5nm, noch bevorzugter bei 280nm +/- 0, 1 nm. According to the invention, the measuring wavelength lies in particular between 2Ωnm and 1μm, preferably between 250nm and 320nm, more preferably at 280nm +/- 5nm and / or 260nm +/- 5nm and / or 254nm +/- 5nm, more preferably at 280nm +/- 0, 1 nm.

Als Halbwertbreite wird erfindungsgemäß insbesondere der in Wellenlänge gemessene Abstand zwischen den Punkten im Intensitätsspektrum According to the invention, the half-value width is, in particular, the distance, measured in wavelength, between the points in the intensity spectrum

angesehen, an denen die Intensität der Messstrahlung des Messspektrums auf die Hälfte ihres Maximalwertes abgefallen ist. Die Halbwertsbreite beträgt erfindungsgemäß insbesondere maximal 1 /5 der Messwellenlänge, vorzugsweise maximal 1 /1 0 der Messwellenlänge, noch bevorzugter maximal 1/50 der Messwellenlänge. viewed at which the intensity of the measuring radiation of the measuring spectrum has fallen to half of its maximum value. The half-width in accordance with the invention is in particular at most 1/5 of the measuring wavelength, preferably at most 1/1 of the measuring wavelength, more preferably at most 1/50 of the measuring wavelength.

Die Tausendstelbreite der Messstrahlung ist erfindungsgemäß insbesondere der in Wellenlänge gemessene Abstand zwischen den Punkten im The thousandth of the width of the measuring radiation according to the invention is, in particular, the distance measured between the points in FIG

Intensitätsspektrum, an denen die Intensität der Messstrahlung des Intensity spectrum at which the intensity of the measuring radiation of the

Messspektrums auf ein Tausendstel ihres Maximalwertes abgefallen ist. Die Tausendstelbreite beträgt erfindungsgemäß insbesondere maximal die Hälfte der Messwellenlänge, vorzugsweise maximal ein Viertel der Spectrum has fallen to one thousandth of its maximum value. The millisecond is according to the invention in particular a maximum of half the measuring wavelength, preferably a maximum of a quarter of

Messwellenlänge. Measuring wavelength.

Gemäß einer vorteilhaften Ausführungsform der Erfindung sind Mittel zur Reduzierung von bezogen auf die Messwellenlänge kurzwelliger und/oder langwelliger Strahlung mindestens um einen Faktor 2, vorzugsweise mindestens um einen Faktor 10, noch bevorzugter mindestens um einen Faktor 100, bezogen auf die eingestrahlte Leistungsdichte der According to an advantageous embodiment of the invention, means for reducing shortwave and / or longwave radiation with respect to the measurement wavelength are at least a factor of 2, preferably at least a factor of 10, more preferably at least a factor of 100, based on the irradiated power density

Messwellenlänge vor dem Eintritt in das Messvolumen vorgesehen. Erfindungsgemäß findet zwischen dem Messvolumen und dem Detektor eine Wellenlängenselektion statt, wobei insbesondere zumindest langwellig zur Messwellenlänge das Quellspektrum begrenzt wird, vorzugsweise mit einem Abfall um mindestens einen Faktor 2, vorzugsweise mindestens um einen Faktor 10, noch bevorzugter mindestens um einen Faktor 1 00, bezogen auf die Messwellenlänge. Der Abfall erfolgt insbesondere in einer Umgebung um die Messwellenlänge, der insbesondere 50/ 1 00, vorzugsweise 2/ 1 00 beträgt. Measuring wavelength provided before entering the measuring volume. According to the invention, a wavelength selection takes place between the measurement volume and the detector, the source spectrum being limited, in particular at least long-wave to the measurement wavelength, preferably with a decrease of at least a factor of 2, preferably at least a factor of 10, more preferably at least a factor of 1 00 to the measuring wavelength. The waste occurs in particular in an environment around the measuring wavelength, which is in particular 50/100, preferably 2/100.

Vorrichtungsgemäß offenbarte Merkmale sollen auch als Device-disclosed features are also intended as

Verfahrensmerkmale als eigenständige oder kombinierte Erfindung offenbart gelten und umgekehrt. Weitere Vorteile. Merkmale und Procedural features disclosed as a separate or combined invention apply and vice versa. Other advantages. Features and

Einzelheiten der Erfindung ergeben sich aus der nachfolgenden Details of the invention will become apparent from the following

Beschreibung bevorzugter Ausführungsbeispiele sowie anhand der Description of preferred embodiments and with reference to

Zeichnungen. Diese zeigen in: Drawings. These show in:

Figur 1 eine schematische, perspektivische Darstellung einer ersten Figure 1 is a schematic, perspective view of a first

Ausführungsform einer erfindungsgemäßen Messvorrichtung und  Embodiment of a measuring device according to the invention and

Figur 2 eine schematische, perspektivische Darstellung einer zweiten Figure 2 is a schematic, perspective view of a second

Ausführungsform der erfindungsgemäßen Messvorrichtung.  Embodiment of the measuring device according to the invention.

In den Figuren sind gleiche und gleichwirkende Bauteile/Merkmale mit den gleichen Bezugszeichen gekennzeichnet. In the figures, identical and equivalent components / features are identified by the same reference numerals.

In der Figur 1 ist eine Quelle 1 dargestellt, die aus einer Lichtquelle 2 und einem wellenlängenselektiven optischen Element 3 gebildet ist. Die FIG. 1 shows a source 1 which is formed from a light source 2 and a wavelength-selective optical element 3. The

Lichtquelle 2 ist als breitbandige Lichtquelle ausgebildet, die ein Light source 2 is designed as a broadband light source, a

breitbandiges Quellspektrum mit einem Strahlengang 7 ausgibt, der, insbesondere linear, bis zu einem Detektor 6 verläuft. Das breitbandige Quellspektrum der Lichtquelle 2 trifft auf das wellenlängenselektive optische Element 3 und beim Durchtritt durch das welleniängenselektive optische Element 3 wird Strahlungsleistung kurzwellig zu einer Messwellenlänge von 280nm deutlich reduziert. Das wellenlängenselektive Element 3 verlässt ein schmalbandiges broadband source spectrum outputs with a beam path 7, which extends, in particular linear, up to a detector 6. The broadband source spectrum of the light source 2 strikes the wavelength-selective optical element 3 and, when passing through the wavelength-selective optical element 3, radiation power is significantly reduced in the short-wave to a measurement wavelength of 280 nm. The wavelength-selective element 3 leaves a narrowband

Quellspektrum mit einer überwiegenden Leistungsdichte in einem Source spectrum with a predominant power density in one

Wellenlängenbereich von über 250nm. In diesem Bereich sind vorzugsweise über 90% der eingestrahlten Leistungsdichte. Wavelength range of over 250nm. In this range, preferably over 90% of the irradiated power density.

Das zumindest unterhalb der Messwellenlänge begrenzte schmalbandige Quellspektrum trifft entlang des Strahlengangs 7 auf ein Messvolumen 4. Das Messvolumen 4 wird durch einen Messraum begrenzt, der zumindest in Richtung des Strahlengangs 7 quer zum Strahlengang 7 angeordnete Fenster 8, 8 ' aufweist. Die Fenster 8, 8 ' sind vorzugsweise orthogonal zum The narrowband source spectrum delimited at least below the measuring wavelength strikes a measuring volume 4 along the beam path 7. The measuring volume 4 is bounded by a measuring space which has windows 8, 8 'arranged transversely to the beam path 7 at least in the direction of the beam path 7. The windows 8, 8 'are preferably orthogonal to the

Strahlengang 7 angeordnet und weisen bevorzugt einen definierten Abstand entlang des Strahlengangs 7 auf. Der Abstand entspricht der Schichtdicke, durch welche das schmalbandige Spektrum entlang des Strahlengangs 7 durch ein in dem Messvolumen angeordnetes Fluid durchtritt. Beam path 7 arranged and preferably have a defined distance along the beam path 7. The distance corresponds to the layer thickness through which the narrow-band spectrum passes along the beam path 7 through a fluid arranged in the measurement volume.

Das Fluid ist entweder in dem Messvolumen 4 statisch oder quer zum Strahlengang 7 strömend angeordnet. The fluid is arranged either in the measuring volume 4 static or transverse to the beam path 7.

Das Fluid weist eine zu bestimmende Stoffkonzentration eines Stoffes (Zielsubstanz), bevorzugt Tryptophan, auf, der eine durch den Detektor 6 messbare Veränderung an dem durch das Messvolumen 4 durchtretenden schmalbandigen Quellspektrum im Messwellenlängenbereich hervorruft. The fluid has a substance concentration to be determined of a substance (target substance), preferably tryptophan, which causes a measurable change by the detector 6 at the passing through the measurement volume 4 narrow-band source spectrum in the measurement wavelength range.

Das schmalbandige Quellspektrum kann in dem Messvolumen 4 eine, insbesondere durch die Zielsubstanz erzeugte, Fluoreszenz bewirken, die unter anderem entlang des Strahlengangs 7 zu einer Verfälschung der von dem Detektor 6 zu messenden Signale führen kann, insbesondere in einem Spektrum mit einer Wellenlänge oberhalb der Messwellenlänge. The narrow-banded source spectrum can cause a fluorescence, in particular caused by the target substance, in the measuring volume 4, which fluoresces, inter alia, along the beam path 7 to a falsification of The detector 6 can carry signals to be measured, in particular in a spectrum having a wavelength above the measuring wavelength.

Aus diesem Grund ist in Strahlengangrichtung hinter dem Messvolumen 4 ein weiteres, wellenselektives optisches Element in Form eines For this reason, in the beam path direction behind the measuring volume 4 is another, wave-selective optical element in the form of a

fluoreszenzreduzierenden Elements 5 im Strahlengang angeordnet. Beim Durchtritt des durch das Messvolumen 4 getretenen schmalbandigen Quellspektrums wird etwaige im Messvolumen 4 erzeugte fluorescence-reducing element 5 arranged in the beam path. Upon passing through the narrow-banded source spectrum which has passed through the measuring volume 4, any potential generated in the measuring volume 4 will be generated

Fluoreszenzstrahlung zumindest überwiegend, vorzugsweise weitgehend, noch bevorzugter vollständig, absorbiert. Somit trifft auf den Detektor 6 zumindest überwiegend, vorzugsweise praktisch ausschließlich das für die Messung der Stoffkonzentration vorgesehene, insbesondere kurzwellig und langwellig begrenzte, schmalbandige Spektrum, das seine Leistungsdichte zumindest überwiegend im Messweilenlängenbereich hat. Das Fluorescence radiation at least predominantly, preferably largely, more preferably fully absorbed. Thus, at least predominantly, preferably practically exclusively, the narrow-band spectrum provided for the measurement of the substance concentration, in particular short-wave and long-wave limited, meets the detector 6, which has its power density at least predominantly in the measurement length range. The

Messspektrum hat bei der Messwellenlänge bevorzugt ein Maximum der Leistungsdichte. The measuring spectrum preferably has a maximum of the power density at the measuring wavelength.

Das fluoreszenzreduzierende Element 5 ist bevorzugt bei 280nm +/- 5nm und/oder 260nm +/- 5nm und/oder 254nm +/- 5nm selektiv. The fluorescence reducing element 5 is preferably selective at 280nm +/- 5nm and / or 260nm +/- 5nm and / or 254nm +/- 5nm.

Der Detektor 6 misst das aus dem Messvolumen 4 und durch das The detector 6 measures this from the measuring volume 4 and through the

fluoreszenzreduzierende Element 5 getretene Licht durch Umsetzung in einen Photostrom über eine elektrische Strommessung, insbesondere einen Photomultiplier. Hieraus kann auf die Stoffkonzentration der Zielsubstanz geschlossen werden. fluorescence-reducing element 5 passed light by conversion into a photocurrent via an electrical current measurement, in particular a photomultiplier. From this, it is possible to deduce the substance concentration of the target substance.

Die in Figur 2 gezeigte Ausführungsform unterscheidet sich von der in Figur 1 beschriebenen Ausführungsform dadurch, dass als Quelle 1 eine schmalbandige Lichtquelle 2 ' vorgesehen ist, so dass auf ein The embodiment shown in FIG. 2 differs from the embodiment described in FIG. 1 in that a narrow-band light source 2 'is provided as the source 1, so that a light source 2' is provided

wellenlängenselektives optisches Element 3 bei dieser Ausführungsform verzichtet werden kann. Die Lichtquelle 2' gibt bereits ein zumindest überwiegend im Messwellenlängenbereich strahlendes Quellspektrum aus und umfasst somit das vor dem Messvolumen 4 angeordnete wavelength-selective optical element 3 can be omitted in this embodiment. The light source 2 'is already at least one predominantly in the measuring wavelength range radiant source spectrum and thus includes the front of the measuring volume 4 arranged

wellenlängenselektive Mittel. wavelength-selective means.

Das fluoreszenzreduzierende Element 5 ' ist bei dieser Ausführungsform bevorzugt zumindest überwiegend, vorzugsweise quasi ausschließlich langweilig zur Messwellenlänge selektiv. In this embodiment, the fluorescence-reducing element 5 'is preferably at least predominantly, preferably almost exclusively boring, selective to the measuring wavelength.

Messvorrichtung und Verfahren zur Bestimmung einer Stoffkonzentration Measuring device and method for determining a substance concentration

B e z u g s z e i c h e n l i s t e C o m p a n c e m e n t i o n s

1 Quelle 1 source

2, 2' Lichtquelle  2, 2 'light source

3 wellenlängenselektives optisches Element  3 wavelength-selective optical element

4 Messvolumen  4 measuring volumes

5, 5' fluoreszenzreduzierendes Element  5, 5 'fluorescence-reducing element

6 Detektor  6 detector

7 Strahlengang  7 beam path

8, 8' Fenster 8, 8 'windows

Claims

P at en t an s p rü c h e P at in t spre che 1. Messvorrichtung zur Bestimmung einer Stoffkonzentration eines in einem Messvolumen (4) angeordnetes Fluids mit: 1. Measuring device for determining a substance concentration of a fluid arranged in a measuring volume (4) with: - einer ein Quellspektrum ausgebenden Quelle (1), a source (1) issuing a source spectrum, - einem vor dem Messvolumen angeordneten wellenlängenselektiven Mittel, a wavelength-selective means arranged in front of the measuring volume, - einem das Messvolumen (4) zumindest in einem Strahlengang (7) begrenzenden Messraum und - A measuring space (4) at least in a beam path (7) limiting the measuring space and - einem Detektor (6) zur Messung einer wellenlängenbezogenen a detector (6) for measuring a wavelength-related Absorption eines durch das Messvolumen (4) getretenen  Absorption of a through the measuring volume (4) occurred Messspektrums, dadurch gekennzeichnet, dass zwischen dem Detektor (6) und dem Messvolumen (4) ein  Measuring spectrum, characterized in that between the detector (6) and the measuring volume (4) a fluoreszenzreduzierendes Element (5) im Strahlengang (7) angeordnet ist. Messvorrichtung nach Anspruch 1 , wobei das fluorescence-reducing element (5) in the beam path (7) is arranged. Measuring device according to claim 1, wherein the fluoreszenzreduzierende Element (5) eine Fluoreszenz zumindest überwiegend, vorzugsweise quasi vollständig, absorbierend ausgebildet ist. fluorescence-reducing element (5) is a fluorescence at least predominantly, preferably quasi-completely, absorbing. Messvorrichtung nach Anspruch 1 oder 2, wobei das Measuring device according to claim 1 or 2, wherein the fluoreszenzreduzierende Element (5) die Intensität der Messstrahlun im Messwellenlängenbereich höchstens um einen Faktur 10, vorzugsweise höchstens um einen Faktor 5, reduzierend ausgebildet ist.. fluorescence-reducing element (5) the intensity of the measuring beam in the measuring wavelength range at most by a factor of 10, preferably at most by a factor of 5, reducing .. Messvorrichtung nach einem der vorhergehenden Ansprüche, wobei das fluoreszenzreduzierende Element (5) mindestens einen, insbesondere an einem Filterrad angeordneten, Filter und/oder einen Monochromator aufweist. Measuring device according to one of the preceding claims, wherein the fluorescence-reducing element (5) has at least one filter, in particular arranged on a filter wheel, and / or a monochromator. Messvorrichtung nach einem der vorhergehenden Ansprüche, wobei die Quelle ( 1 ) als Measuring device according to one of the preceding claims, wherein the source (1) as a) schmalbandige Lichtquelle (21 ) oder a) narrowband light source (2 1 ) or b) breitbandige Lichtquelle (2) mit nachgeschaltetem b) broadband light source (2) with downstream wellenlängenselektiven opti schen Element (3 )  wavelength-selective optical element (3) ausgebildet ist. is trained. Messvorrichtung nach einem der vorgehenden Ansprüche, dadurch gekennzeichnet, dass die Messvorrichtung ein Messspektrum zwischen 200 nm und 1 5 μπι, insbesondere zwischen 250 nm und 320 nm, vorzugsweise von 280 nm +/- 5 nm und/oder 260 nm +/- 5 nm und/oder 254 nm +/- 5 nm messend ausgebildet ist. Messvorrichtung nach einem der vorhergehenden Ansprüche, wobei der Detektor (6) eine Messwellenlänge zwischen 200 nm und 15 μτχι, insbesondere zwischen 250 nm und 320 nra, vorzugsweise von 280 nm +/- 5 nm und/oder 260 nm +/- 5 nm und/oder 254 nm +/- 5 nm messend ausgebildet ist. Measuring device according to one of the preceding claims, characterized in that the measuring device a measuring spectrum between 200 nm and 1 5 μπι, in particular between 250 nm and 320 nm, preferably from 280 nm +/- 5 nm and / or 260 nm +/- 5 nm and / or 254 nm +/- 5 nm measuring is formed. Measuring device according to one of the preceding claims, wherein the detector (6) has a measuring wavelength between 200 nm and 15 μτχι, in particular between 250 nm and 320 nm, preferably 280 nm +/- 5 nm and / or 260 nm +/- 5 nm and / or 254 nm +/- 5 nm measuring is formed. Verfahren zur Bestimmung einer Stoffkonzentration eines in einem Messvolumen (4) angeordneten Fluids mit folgenden Schritten, insbesondere folgendem Ablauf: Method for determining a substance concentration of a fluid arranged in a measuring volume (4) with the following steps, in particular the following sequence: Ausgeben eines Quellspektrums mit einem zumindest teilweise durch das Messvolumen (4) verlaufenden Strahlengang (7), wobei wellenlängenselektive Mittel vor dem Messvolumen vorgesehen sind, Outputting a source spectrum with a beam path (7) extending at least partially through the measurement volume (4), wherein wavelength-selective means are provided before the measurement volume, Messung einer wellenlängenbezogenen Absorption eines durch das Messvolumen (4) getretenen Messspektrums mittels eines Detektors (6), dadurch gekennzeichnet, dass zwischen dem Detektor (6) und dem Messvolumen (4) eine Fluoreszenz im Strahlengang (7) reduziert wird. Measurement of a wavelength-related absorption of a measuring spectrum passed through the measuring volume (4) by means of a detector (6), characterized in that a fluorescence in the beam path (7) is reduced between the detector (6) and the measuring volume (4).
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US8901513B2 (en) * 2011-03-08 2014-12-02 Horiba Instruments, Incorporated System and method for fluorescence and absorbance analysis
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Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ROBERT M HOFFMAN ET AL: "PHOTOCHEMICAL TECHNIQUE. III. QUARTZ CAPILLARY ARC LAMPS OF BISMUTH, CADMIUM, LEAD, MERCURY, THALLIUM AND ZINC", J. AM. CHEM. SOC., vol. 54, no. 11, 1 November 1932 (1932-11-01), pages 4226 - 4235, XP055295322, DOI: 10.1021/ja01350a012 *

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