JPH0387647A - Sample injecting device - Google Patents

Abstract

PURPOSE:To obtain an injecting device which can be automatized easily, and can inject simultaneously the samples of a trace into two columns with high reproducibility by rotating simultaneously a pair of rotors held therebetween by valve seats and having a weighing hole, centering around a rotary axis by a prescribed sequence. CONSTITUTION:Ceramics discoid rotors 103, 104 held therebetween by discoid valve seats 101, 102 are provided. The rotors 103, 104 rotate simultaneously, and a weighing hole is formed due to a fact that two disks are superposed. In this state, in a state for injecting a sample into capillary columns 1a, 1b, the rotors 103, 104 rotate, the weighing hole filled with the sample by a microsyringe 9 is connected between the columns 1a, 1b, the center part of the weighing hole is connected to the passage of a buffer liquid, and the sample is forcedly fed into the columns 1a, 1b by hydraulic pressure of the buffer liquid. In such a manner, the samples of a trace of the columns 103, 104 can be injected simultaneously, and the samples whose moving directions are different can be measured simultaneously. The injection quantity of the sample is determined by the inner capacity of the weighing hole, the connection time, and the head pressure of the buffer liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is directed to:
lary electrophoresis, CE
) The present invention relates to a sample injection device suitable for use when simultaneously analyzing a small amount of sample using two columns in the device.

<Prior art> Capillary electrophoresis is a type of electrophoretic analysis method that performs separation analysis using the difference in electrical mobility of a sample to be measured in a high electric field. The device used for capillary electrophoresis analysis (so-called capillary electrophoresis device) differs greatly from other electrophoresis methods in that the components to be measured are separated inside a so-called capillary column, which is a hollow column.
is usually a hollow capillary tube, high voltage power supply,
It consists of a detector, sample injector, etc.

Furthermore, in the apparatus used for the capillary electrophoresis analysis method as described above, a sample injection device is installed at one end of the capillary column, and a detector is installed at the other end. Separation and detection are performed by applying a high DC voltage to both ends of the capillary column. However, because the sample moves toward the electrode with the opposite polarity to its own charge (polarity), it is not always necessary to It does not necessarily move to the sample injector fFl), but may also move between sample injectors.

Therefore, it is impossible to completely detect ions of opposite polarity in a sample in a single measurement. However, if measurements are performed using electroosmotic flow or forced liquid delivery using a pump, etc., it is not possible to detect and measure ions moving in different directions to a certain extent (only in samples with low mobility). It is possible. However, even in this case, it is impossible to measure ions with high mobility. Furthermore, in order to measure all ions of opposite polarity in the sample, there is the inconvenience that the polarity of the high voltage must be reversed and the measurement performed twice.

The solution to this problem is to prepare two sets of capillary columns and detectors, bundle the two capillary columns, insert them into the sample solution, and use the difference in the water level of the sample solution (head difference) to inject the sample. It is easily possible to do this by inserting the two capillary columns together into a buffer tank and applying a high voltage. However, although this method is very easy to carry out manually, it has the drawback that good reproducibility cannot be obtained because it is difficult to control head differences. Of course, it is possible to obtain good reproducibility by mechanizing the process, but it has the disadvantage of resulting in a rather bulky device.

<Problems to be Solved by the Invention> The technical problems to be solved by the present invention are that it can be used in a capillary electrophoresis device, is easy to automate, and has good reproducibility. An object of the present invention is to provide a sample injection device that can simultaneously perform injections into columns.

Means for Solving the Problems> The present invention provides a sample injection device that includes a pair of fixed valve seats and a pair of rotors that are sandwiched between the valve seats and have a metering hole and rotate simultaneously around a rotation axis. and a means for rotating this rotor in a certain sequence, and a means for supplying a buffer solution at a constant water level, and two systems for flowing the buffer solution and sample from the one valve seat through the rotor to the other valve seat. and two capillary columns for sample separation are respectively connected to the pair of valve seats, and before the sample is injected into the capillary column, the sample is introduced from one of the valve seats. In a state where the sample is discharged from the other valve seat through the metering hole and the sample is injected into the capillary column, the metering hole filled with the sample in the rotor is connected to the two capillary columns, and the pair of rotors is connected to the metering hole filled with the sample. The central part of the formed hole is brought into contact with the slow tr liquid, and a minute amount of the sample is injected into the two capillary columns by the hydraulic pressure of the buffer solution generated by the means for creating a constant water level, and the sample is injected into the two capillary columns. When the sample is to be separated after being injected into the two capillary columns, the buffer solution introduced from one of the valve seats is connected to the inlets of the two capillary columns and discharged while washing this portion. This is a solution to a problem.

Function> The above technical means works as follows. That is, before the sample is injected into the capillary column,
After a sample is injected from the one valve seat using a microsyringe or the like and fills the measuring holes provided in the pair of rotors, the remaining sample is discharged from the other valve seat.

When the sample is injected into the two capillary columns, the pair of rotors rotates, the measuring hole filled with the sample is connected between the two capillary columns, and the center part of the measuring hole is injected into the flow of the buffer solution. The sample filled in the measuring hole is connected to the two channels under the hydraulic pressure of the buffer solution.
is pumped into two capillary columns. The amount of the sample injected into the two capillary columns is determined by the content of the metering hole, the time the metering hole is connected to the capillary column, and the head pressure of the M solution, and by keeping these constant. The minute sample required for analysis can be injected with good reproducibility.

After the sample is injected into the two capillary columns, the pair of rotors rotates again and a high voltage is applied to separate the sample. At this time, the inlet portions of the two capillary columns are constantly cleaned by the Mi solution introduced from one of the valve seats. This is to prevent the capillary column from being blocked by dust, etc., and also to prevent gas generated by electrolysis during high voltage application from entering the capillary, and to prevent interruptions in measurement due to the inflow of generated gas. be.

<Example> Hereinafter, the present invention will be explained in detail using the drawings. 1st
The figure is an explanatory view of an example of use of the embodiment of the present invention, and shows the configuration and flow path when the sample injection device according to the present invention is incorporated into a capillary electrophoresis device. In this figure, 8
is a constant water level generator, and the capillary column 1.1'
The buffer solution is delivered due to the head difference generated between the two. The two pipes 8a and 8b in which this constant water level creator is installed are connected in the middle, and a pump 8C is applied to the water from the bottom of the pipe 8a.
The M cargo liquid stored in the cargo liquid tank 8d is sent. The solvent that overflowed in the tube 8a is returned to the buffer tank 8d via the tube 8b.

9 is a microsyringe for supplying a sample, and 10 is a sample injection valve for injecting a predetermined minute amount of sample into the capillary column 1.

11 is a switch for applying a high voltage power supply E to the capillary column 1.1', and is operated by a control signal from a sequencer to be described later.

A sequencer 12 provides control signals to the sample injection valve 10, the switch 11, and the signal processing section 13 according to a predetermined sequence. Note that 14 is an ammeter, 15 is a recorder, and 16 is a constant temperature bath.

The sample injector 10 will be explained in detail with reference to the exploded perspective view of FIG. 101.102 is a disc-shaped valve seat (stator)
, 103 and 104 are disc-shaped rotors made of ceramic, for example, which are sandwiched between these valve seats, and the two discs rotate simultaneously.

A metering hole is formed in this pair of rotors by overlapping two disks. The valve seat 101 has a hole 101a.
~101d is provided, and the rotor 103 is provided with a hole 103a.
~103cl is provided, and the rotor 104 has a hole 10
4a to 104d are provided, and the valve seat 102 has a hole 102.
a to 104d are provided.

Shafts are inserted through the holes 101a, 103a, 104a, and 102a. An arcuate groove 103e is formed in the hole 103d of the rotor 103 on the surface that contacts the valve seat 101.
The rotor 104 has an arcuate bowl 104e formed on its surface that contacts the rotor 103, and an arcuate groove 104f formed on its surface that contacts the valve seat 102.

Among these, hole 102d is a buffer solution inlet, hole 101d is a buffer solution outlet, hole 101b is a sample injection hole, and hole 102 is a buffer solution inlet.
b is the sample discharge hole. In addition, holes 101c and 102
c is the hole to which the capillary column is connected.

Figure 3 is an explanatory diagram to explain the operation of the sample injector that has been subjected to the 'N4 commands in this way. Figure (A) shows the state during measurement, and Figure (A) shows the state when injecting the sample. Hereinafter, the operation of the sample injector will be explained with reference to FIG.

In the state before sample injection, that is, in the state at the time of measurement, the holes 101b, 103b, 104b, and 102b are
are connected in a straight line. In this state, the sample given from the microsyringe 9 passes through the hole 101b and fills the measuring hole (flow path connecting 103b and 104b). Excess sample is discharged from the hole 102b.

When the rotors 103 and 104 are switched as shown in figure (b), either the metering hole (flow path connecting 103b and 104b) or the hole 10
It is connected to capillary columns 1 and 1' through 1C, 1 and 02C, and the sample filled in the measurement hole (channel connecting 103b and 104b) is pumped into capillary column 1.1' by the flowing buffer as shown in the figure. Ru. Incidentally, the rotors 103 and 104 are switched at a constant timing by a motor or the like (not shown) based on a control signal from the sequencer 12. Capillary column 1.1
′ is injected with a part of the sample filled in the measuring hole (flow path connecting 103b and 104b);
03b and 104b) is capillary column 1.
, 1° and the head pressure of the y1 solution.

After this, the rotors 103 and 104 are brought into the state shown in FIG. At this time, the holes 102d and 104d, 103d, which are the inlets for the llj liquid, and the hole 10, which is the outlet for the M cargo liquid.
1d are connected by grooves 104f and 103e. In this state, the buffer solution from the constant water level creator 8 is flowing to wash the inlets of the capillary columns 1 and 1°. Here, by closing the switch 11, the high-voltage power source E is applied to both ends of the capillary column 1.1, and separation is performed. After the measurement is completed, the switch 11 is turned off to complete the analysis.

In addition, since the amount of sample injected into the capillary column 1.1° is extremely small (1 to 10 nl), in the embodiment of the present invention, a portion of the sample filled in the measuring hole is partially injected to I try to get a small amount of sample. but,
If the thickness of the rotors 103 and 104 is made thinner and the diameter of the measuring hole is made smaller so that the optimum amount of sample required for analysis can be obtained during most of this measurement, the measuring hole will be filled. The entire amount of the sample is injected into the capillary column 1°1°.

<Effects of the Invention> According to the present invention, it is possible to simultaneously inject extremely small amounts of samples into the two capillary columns, and by installing a detector between the downstream of each capillary, it is possible to inject samples ( This enables simultaneous measurement of samples with opposite polarity.

Further, the amount of sample to be injected in the sample injector of the present invention is determined by the time during which the measuring hole is connected to the capillary column and the head pressure of the buffer solution, and by keeping these constant, the minute amount necessary for analysis can be reduced. Samples can be injected with good reproducibility. Also, by changing these, it becomes a variable capacity sample injector.

Furthermore, during measurement, the connecting portion of the capillary column is constantly cleaned with the 11'r liquid, so that the capillary column is not clogged with dust, and gas generated by electrolysis when high voltage is applied does not enter the capillary. It also has the advantage that there is no intrusion, and there is no interruption in measurement due to the inflow of generated gas, so it also has the advantage of being able to perform measurements with good reproducibility.

If simultaneous analysis of components with different polarities is not required, analysis can be performed like a normal capillary electrophoresis device by attaching a blind stopper to one capillary connection boat of the sample injector of this embodiment of the present invention. There are also advantages.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an example of use of an embodiment of the present invention, FIG. 2 is an exploded perspective view of a micro-sample injection valve, and FIG. 3 is an explanatory diagram of the operation of the micro-sample injection valve. 1.1- Capillary column, 3...
... Buffer tank, 4 ... Waste liquid switching valve, 8 ... Constant water level creator, 10 ... Sample injector, 11 ... Switch, 12・・・・・・
・Sequencer, 14... Ammeter, 15...
...Recorder, 16...Thermostatic chamber, Fig. 3

Claims (1)

[Claims] A pair of fixed valve seats, a pair of rotors sandwiched between the valve seats and having a metering hole and rotating simultaneously around a rotation axis,
means for rotating the rotor in a fixed sequence;
means for supplying a buffer solution at a constant water level, and providing two channels for flowing the buffer solution and the sample from the one valve seat through the rotor to the other valve seat, Two capillary columns for sample separation are connected respectively, and before the sample is injected into the capillary column, the sample is introduced from the one valve seat and discharged from the other valve seat through the metering hole, In addition, when the sample is injected into the capillary column, the measuring hole filled with the sample in the rotor is connected to the two capillary columns, and the center part of the hole formed by the pair of rotors is injected into the buffer solution. A state in which a minute amount of the sample is injected into the two capillary columns by the liquid pressure of the buffer solution generated by the means for contacting and creating the constant water level, and after the sample is injected into the two capillary columns, the sample is separated. In the sample injection device, the buffer solution introduced from the one valve seat is connected to the inlets of the two capillary columns, and is discharged while washing this portion.