TH90676B - Array biosensor using plasmon surface wave technique. - Google Patents

Abstract

This invention, DC60, represents a technique for measuring the resonant wavelength of a plasmon surface waveform sensor array that minimizes mechanical movement and vibration, resulting in higher accuracy. It utilizes a micromirror as the primary device for scanning and selecting the beam to various positions on the sensor array, replacing the electric motors used in previous inventions. Because the micromirror consists of tiny mirrors, its operation is vibration-free, minimizing measurement disruption. Furthermore, its operation can be electrically controlled, enabling automatic scanning of the sensor array position. The combination of the micromirror with the plasmon surface waveform measurement technique (resonant wavelength measurement), along with a design that allows for precise positional detection of the incident beam on the sensor array during measurement using a strategically placed camera, ensures consistent positioning. If movement occurs due to sample changes, the instrument can automatically detect and adjust the position, enhancing user convenience. The plasmon surface waveform sensor array in this invention is designed for compatibility with a wide range of sample materials, allowing for flexible application with diverse sample compositions. Users can operate the instrument immediately without needing to reposition it. Therefore, in instrument manufacturing, the various positions of the components can be permanently fixed, or the components can be enclosed in a sealed box, providing better protection from dust and moisture. The instrument is also more durable and resistant to impact. This invention eliminates the need for electric motors to scan the sensor array position, significantly reducing the sensor area and maintenance costs. This invention demonstrates a developed technique for measuring the resonant wavelength of a plasmon surface wave sensor array, minimizing mechanical movement and vibration for higher accuracy. A micromirror is used as the primary device to scan and select the beam to various positions on the sensor array, replacing the electric motors used in previous inventions. Because the micromirror consists of tiny mirrors, its operation does not generate vibrations that affect the measurement. Furthermore, the micromirror's operation can be controlled electrically, allowing for automatic scanning of the sensor array position. The use of the micromirror, combined with the plasmon surface wave measurement technique (resonant wavelength measurement), and the design to determine the beam's position on the sensor array, results in a highly accurate measurement. During measurement, using a properly positioned camera ensures that the measurement is at the same location. If movement occurs due to changes in the sample, the instrument can be designed to automatically detect and adjust the position, making it convenient to use. The plasmon surface wave array sensor of this invention is designed to be compatible with a wide range of samples. This allows for immediate use with different samples without the need for repositioning. Therefore, the instrument's components can be permanently positioned or enclosed in a sealed enclosure, providing better protection from dust and moisture, and increasing its resistance to impact. This invention eliminates the need for an electric motor to scan the sensor array, significantly reducing the sensor area and lowering maintenance costs.

Claims (13)

1. A plasmon surface wave sensor array consists of a polychromatic light source, which directs the light into parallel beams of an appropriate magnitude. This beam is oriented along a central optical axis. A polarizer is a device that selects or separates the polarization direction of the light, as described above. This device adjusts the polarization direction of the beam to a direction suitable for stimulating plasmon surface waves. A suitable sensor array for plasmon surface wave stimulation is mounted on a supporting prism. Such a sensor array consists of a gold film approximately 40 to 50 nanometers thick. This film is coated on a transparent supporting prism or on a flat sheet with a refractive index equal to that of the supporting prism and mounted on the supporting prism. The mounting may be achieved using a liquid with a refractive index equal to that of the prism to ensure a tight junction. Next to the gold film is a layer of dielectric material. This dielectric material has a refractive index lower than the refractive index of the supporting prism. This dielectric material may... A sensor array consists of a thin film of polymer and/or a layer of protein molecules or other suitable biological materials for specific measurements or applications. Each measurement point on the sensor array, called a "pixel," may be coated with a different or the same biological material, depending on the suitability for the application. A micromirror array is positioned to reflect light from a light source onto the sensor array through a supporting prism. This causes the angle of incidence within the prism to be greater than the critical angle, which can induce plasmon surface waves. The micromirror array selectively reflects only the light beam that strikes a given pixel of the sensor array, while other parts of the beam are redirected to reflect in directions that will not affect the measurement. A spectrometer, or optical spectrometer, measures the spectrum of the light reflected from each pixel of the sensor array. The resulting spectral data can be analyzed to determine the resonant wavelength, which reveals the refractive index of the dielectric material on each pixel of the sensor array. This device typically consists of a light source, a sensor array, a supporting prism, and a micromirror array. The spectrometer, or spectral analysis device, is positioned along the central axis and in a suitable location, following the principle of refractive index measurement using the surface wave plasmon technique. These devices may be interconnected via a computer to control their operation and ensure coordinated performance. 2. Plasmon surface wave sensor array, which consists of a polychromatic light source arranged as a parallel beam with an appropriate beam size, aligned along a central optical axis. A polarizer is a device that selects or separates the polarization direction of the light, adjusting it to a direction suitable for stimulating plasmon surface waves. A suitable sensor array for plasmon surface wave stimulation is mounted on a supporting prism. This sensor array consists of a gold film approximately 40 to 50 nanometers thick, coated on a transparent supporting prism or on a flat sheet with a refractive index equal to that of the supporting prism and mounted on the prism. The mounting may be facilitated by using a liquid with a refractive index equal to that of the prism. Next to the gold film is a layer of dielectric material with a refractive index lower than that of the supporting prism. This dielectric material may consist of a thin film of polymer and/or a layer of protein molecules or other suitable biological materials for a particular measurement or application. Each measurement point of the sensor array, called a "pixel," may be coated with a different or the same biological material, depending on the suitability for the application. A micromirror array, positioned along the aforementioned central axis and strategically located to reflect the light from the sensor array onto the aperture of a spectrometer or spectrometer, selects only the portion of the light beam that strikes a designated pixel of the sensor array and reflects it to the spectrometer or spectrometer. Other parts of the beam are redirected to other directions so as not to affect the measurement. A spectrometer measures the spectrum of the light reflected from each pixel of the sensor array. The resulting spectral data can be used to determine the resonant wavelength, which reveals the refractive index of the dielectric material on each pixel of the sensor array. This device typically consists of a light source, a sensor array, and a prism supporting the micromirror array. The spectrometer, or spectral analysis device, is positioned along the central axis and in a suitable location, based on the principle of refractive index measurement using the surface plasmon wave technique. These devices may be interconnected via a computer to control their operation and ensure coordinated performance. 3. Plasmon surface wave array sensors, as per claim 1 or 2, also include a flow cell (which may be more than one) attached to the sensor array to guide the sample to be measured to the sensor area, with a flow control system to regulate the flow of the sample in and out, suitable for each specific application. 4. A plasmon surface wave array sensor under claim 1 or 2 that uses optical fibers to transmit light from such light source to the sensor array, with the purpose of allowing the light source to be placed at a distance that does not interfere with the operation of the sensor array. 5. A plasmon surface wave array sensor pursuant to any one of claims 1, 2, or 4, in which the focusing of light into such optical fiber is achieved using a lens or other condensing device to improve the efficiency of focusing the light into the end of the beam. 6. A plasmon surface wave array sensor as per claim 1, which is further incorporated with a lens or other optical device placed along the aforementioned central axis, and with a pinhole placed at the focal point of the lens and other optical device and positioned between the said light source and the said micromirror, to magnify, focus, concentrate, or arrange the light beam into parallel beams with appropriate size and intensity distribution for the operation of the said micromirror. 7. A plasmon surface wave array sensor under claim 2, further comprising a lens or other optical device placed along the aforementioned central axis, with a pinhole placed at the focal point of the lens and other optical device and positioned between the light source and the sensor array, to magnify, focus, combine, or arrange the light beam to have a size and intensity distribution appropriate to the size of the sensor array. 8. A plasmon surface wave array sensor as per claim 1, which is further incorporated with a lens or other optical device, is placed along the aforementioned central axis and positioned between the micromirror and the said sensor array to amplify or reduce the size of the beam to a size appropriate to the size of the micromirror and the said sensor array. 9. A plasmon surface wave array sensor pursuant to claim 1 or 2, where such polarizer is placed at any position between the light source and such spectrometer and is aligned with its central axis. 10. A plasmon surface wave array sensor as per claim 1, which is further incorporated with a beam splitter or other beam splitting device to split the reflected beam from the said sensor array into two beams, and incorporating a CCD camera, CMOS camera, or other imaging camera placed along the said central axis and positioned to receive one of the reflected beams from the beam splitter for the purpose of determining the position of the incident beam and the position of the said sensor array. 11. A plasmon surface wave array sensor under claim 2, which is further incorporated with a beam splitter or other beam splitting device to split the reflected beam from the micromirror into two beams, and incorporating a CCD camera, CMOS camera, or other imaging camera placed in the central axis and positioned to receive one of the reflected beams from the beam splitter for the purpose of determining the position of the incident beam and the position of the sensor array. 12. Plasmon surface wave array sensors pursuant to claim 1 or 2, where such spectrometer includes any optical device capable of being used to indicate the spectrum of light, and includes spectrometers with optical fiber apertures. 13. A plasmon surface wave array sensor as described in claim 1 or 2, further comprising lenses and other optical devices, is placed in the central axis and positioned in front of the aperture of the spectrometer to focus the light beam appropriately to the size of the aperture of the spectrometer.