JP2008089579A - Biochemical measuring device - Google Patents

Abstract

【Task】
It is an object of the present invention to provide a biochemical measuring apparatus suitable for a sensor chip for multi-channel measurement, which can be downsized and inexpensive.
[Solution]
The present invention is provided with a light projecting system fiber switching mechanism for selectively selectively passing the light projected from one of the n optical fibers in the middle of the n optical fibers of the light projecting system corresponding to the n channel. One spectrometer receives light received from n light receiving optical fibers in common. Thereby, the measurement data of the reflection spectrum of n optical thin film sensor units can be obtained with one spectroscope.
[Selection] Figure 1

Description

  The present invention relates to a biochemical measurement apparatus, and is suitable for measurement using a multi-channel measurement sensor chip that measures the binding of biochemical substances such as antibody reactions in multiple channels, and is inexpensive and can be miniaturized. It relates to the improvement of the apparatus.

Conventionally, chemical sensors using the light interference color of an optical thin film are known. This sensor has a peak where the reflection intensity in the direction perpendicular to the thin film becomes substantially zero at a specific wavelength when light is irradiated with the thickness of the optical thin film being 1/4 or an odd multiple of the wavelength of visible light. The sensor produces a reflection spectrum having a predetermined interference color as reflected light.
For example, when a monomolecular layer of a ligand (functional group) is provided as a biochemical substance (probe) on the thin film of the sensor, the position of the peak wavelength in the reflection spectrum of the sensor is shifted by the amount of the thickened film. . In addition, if a sample (analyte protein, etc.) adheres to the ligand monolayer, the interference color changes and the reflection spectrum changes due to the position of the peak wavelength of the reflected light being shifted by the thickness of the film. The adhesion of the sample (analyte protein, etc.) to the optical thin film can be measured by this sensor from the color or reflection spectrum.

As a method for measuring the binding of biochemical substances such as antibody reactions, a sensor chip in which an optical thin film is provided on silicon and a biochemical substance (probe) is provided thereon is known as another chemical sensor. Furthermore, the optical thin film is made of gold and the surface is a biochemical substance (probe). For example, a ligand such as carboxymethyl dextran is attached to form a sensor chip. Some chemical sensors capture the change in rate.
The surface plasmon sensor chip generates reflected light corresponding to the binding or binding / dissociation of a ligand and a sample (analyte protein) with respect to the irradiation light irradiated through the prism. The reflected light causes energy loss at a specific angle. Therefore, the energy loss seen at this specific angle is detected as a trough (peak) where the reflection intensity is attenuated, and this peak is detected by the measuring device via the prism. Further, the time change of the mobility (peak shift) of the peak angle (SPR angle) is measured using this peak as the SPR angle (disappearance angle). This measures the bond or bond-dissociation change between the two molecules.
When measuring the binding or binding / dissociation between two molecules, it is necessary to send the solution at a constant flow rate to the flow cell that forms the channel flow path with respect to the sensor chip during the measurement.

Since this gold optical thin film sensor chip is difficult and expensive to attach a ligand to gold, silicon nitride (SiN) is deposited on the surface of a silicon substrate to form an optical thin film. A sensor chip using a light interference color is known. Since silicon nitride easily adheres to a ligand, a measurement device that uses this as a sensor chip irradiates the sensor chip with irradiation light and performs wavelength analysis on the reflected light due to optical interference of the optical thin film obtained thereby. A spectrum waveform can be obtained, and binding or binding / dissociation of the bound sample can be measured as a temporal change in the peak shift of the interference spectrum waveform.
A sensor chip that uses a light interference color by forming a metal thin film as an optical thin film on a glass substrate is known (Patent Documents 1 and 2). Also known is a microfluidic device that forms a channel flow path in a sensor chip and sends liquid to the channel flow path during measurement (Patent Document 3).
JP 2004-132799 A JP 2005-321196 A JP 2005-181095 A

In order to measure the temporal change of the peak shift of the reflected light due to the optical interference of the optical thin film, it is necessary to measure the spectrum of the reflected light obtained from the sensor chip with high accuracy. Therefore, as described in Patent Documents 1 and 2, a multi-channel photoreceiver is provided for a sensor chip in which a large number of optical thin film regions are formed, and measurement results for each channel are obtained, and an average value thereof is calculated. Further, in order to obtain the peak wavelength, a process of approximating the attenuation curve of the reflection spectrum by the least square method or the like is performed. Further, the multi-channel sensor chip makes it possible to measure the binding of biochemical substances for each channel.
However, four spectroscopes are required for a sensor chip for 4-channel measurement as disclosed in Patent Documents 1 and 2. This is because the reflected light from each optical thin film is independent and cannot be mixed at the light stage to analyze their reflection spectra.
As a result, the biochemical measuring device for multi-channel measurement is increased in size and the spectroscope is expensive, which raises the problem of raising the price of the entire device. In addition, when the multi-channel simultaneous measurement is performed, the translucent sensor chip has a problem in that light leaks between the channels and the measurement accuracy decreases.

In addition, the sensor chip for measuring the peak shift requires an input port and an output port for the buffer solution as shown in Patent Documents 1 and 2 because of the measurement in the liquid feeding state. Therefore, in the sensor chip, unless the input port and the output port are provided at a location different from the optical thin film sensor unit, the optical thin film sensor unit cannot be irradiated and the reflected light from the optical thin film sensor unit cannot be received. There is. However, if the sensor chip is specially provided with an input port and an output port as in Patent Documents 1 and 2, the sensor chip itself must be large, which causes a problem in handling the sensor chip.
An object of the present invention is to solve such problems of the prior art, and to provide a biochemical measuring device suitable for a sensor chip for multi-channel measurement, which can be downsized and inexpensive. is there.

  In order to achieve such an object, the biochemical measuring apparatus according to the present invention includes a sensor chip having n (n is an integer greater than or equal to 2) optical thin film sensor units and n optical thin film sensors. And selectively projecting light from one of the n optical fibers provided in the middle of the n light projecting optical fibers. A light projecting system fiber switching mechanism that passes and blocks the remaining light projecting light, n light receiving system optical fibers that respectively receive reflected light from the n optical thin film sensor units, and n light receiving system optical fibers Select the irradiation light from any one of the light projecting optical fibers by controlling the light projecting fiber switching mechanism and one spectroscope that receives each reflected light from the light incident side in common And a control unit that performs the optical operation of the selected light projecting optical fiber. The reflected light from the film sensor unit is for spectroscope.

Thus, in the present invention, one of the n optical fibers in the middle of the n optical fibers of the light projecting system provided for the n optical thin film sensor units corresponding to the n channel. Is provided with a light projecting fiber switching mechanism that selectively and sequentially passes the light from the n light receiving system optical fibers. Even if it exists, the measurement data of the reflection spectrum of n optical thin film sensor parts can be obtained according to light projection system fiber switching. Note that each of the n light projecting optical fibers may be a bundle of a plurality of bundles.
Here, when the spectroscope is a diffraction grating type, the diameter of each optical fiber of the n light receiving systems that guides reflected light is set to 1 / n of the length of the light incident side slit of the diffraction grating type spectroscope. As a result, n lines can be arranged along the slit in correspondence with the slit length direction. Therefore, one light projecting optical fiber is sequentially selected according to the time-division switching of the light projecting fiber switching mechanism, and the output of the diffraction grating type spectroscope corresponding to each of the n channels is accordingly selected. If the division is sequentially obtained, the measurement data for n channels can be obtained sequentially by time division even if there is only one spectrometer.
When the input light uses one spectrometer, a light receiving system fiber switching mechanism may be provided to select one of the n light receiving system optical fibers and input it to the spectrometer.

Therefore, a translucent sensor chip in which n microchannels are formed can be used as the sensor chip. As the sensor chip, in particular, in a semiconductor process, a silicon rubber is formed on the surface of a silicon substrate to form an optical thin film, and a silicon rubber having n microchannels formed on a substrate, for example, PDMS (polydimethylsiloxane) An n-channel sensor chip formed by bonding a substrate can be used. Furthermore, if this sensor chip is provided with pods at both ends of each microchannel and this pod is connected to the input port and output port of the liquid feed, the thickness of the sensor chip can be reduced. And the handling becomes easy. The optical thin film sensor unit is formed by forming a biochemical substance such as a ligand on the optical thin film as a probe.
Even if a translucent sensor chip made of PDMS is used, there is no light leakage between the channels because the projected light becomes one by switching the light projecting fiber switching mechanism. As a result, there is no problem of a decrease in measurement accuracy.
As a result, it is possible to realize a biochemical measurement apparatus suitable for a sensor chip for multi-channel measurement, which can be downsized and inexpensive.

FIG. 1 is a block diagram of a biochemical measuring apparatus according to an embodiment to which the present invention is applied. FIG. 2A is a plan view of a sensor chip in which two microchannels are formed. FIG. FIG. 3 is an explanatory diagram of a measurement stage, FIG. 4 is a front view of a two-channel light projecting fiber switching mechanism, and FIG. 5 is an optical fiber and a diffraction grating type spectrometer. FIG. 6 is a sectional view of the optical fiber bundle of the light projecting system and the light receiving system, and FIG. 7 is the measured interference spectrum and movement of the valley of the reflected light. FIG. 8 is an explanatory diagram of an 8-channel light projecting fiber switching mechanism, and FIG. 9A is a diagram of a light receiving fiber switching mechanism in another embodiment to which the present invention is applied. Fig. 9 (b) is a plan view showing the receiving of the light receiving system fiber switching mechanism. FIG. 9C is a diagram showing the arrangement of fibers on the spectrometer side of the light receiving system fiber switching mechanism, and FIG. 10 is an explanatory diagram of the switching timing of the light projecting system fiber switching mechanism and the light receiving system fiber switching mechanism. .
In the respective drawings described above, equivalent components are denoted by the same reference numerals, and description thereof is omitted.
In FIG. 1, reference numeral 10 denotes a biochemical measurement apparatus, which includes a measurement stage 1, a liquid feeding system 2, a temperature adjustment system 3, a light projecting system 4, a light receiving system 5, a light receiving control circuit 6, It comprises a data processing / control device 7 and a USB hub 8 and the like, and measures biochemical substance binding or binding / dissociation in the sensor chip 9.
The measurement stage 1 includes a sensor chip mounting table 16 mounted on the constant temperature base 11 of the temperature adjustment system 3, a chip cover 17 provided on the sensor chip mounting table 16, and a moving table 12 provided on the top. have.

The movable table 12 supports two light projecting optical fiber bundles and two light receiving optical fibers, and the constant temperature base 11 holds the sensor chip 9 at a predetermined temperature.
The moving table 12 moves up and down, and is attached to a bracket 14 standing on the apparatus base 13 on the back surface of the measurement stage 1 via a lifting mechanism (not shown). Reference numeral 15 denotes an abutting stopper bar for stopping the lowering of the movable table 12, and the root is implanted in the apparatus base 13. The moving table 12 is provided with an adjustment knob 12a for finely adjusting the stop position, and thereby the stop position of the moving table 12 with respect to the abutting stopper bar 15 is finely adjusted. As a result, the position of the tip (bundle tubes 40a, 40b) of the light projecting / receiving optical fiber with respect to the sensor chip 9 (its optical thin film sensor section) can be finely adjusted with respect to the sensor chip.

The sensor chip 9 is a microchip having two channel flow paths. This is because silicon nitride (SiN) is formed on the surface of the silicon substrate 9a in the semiconductor process as shown in the plan explanatory view of FIG. 2A and the AA cross-sectional explanatory view of FIG. 2B. A base 91 having an optical thin film 9b is formed, and a facing substrate 94 made of PDMS having at least two microchannels 92 and 93 formed thereon is bonded to the base 91. The thickness of the silicon substrate 9a is about 0.7 to 0.8 mm, and the thickness of the optical thin film 9b is about several hundred nm.
Pods 94 to 97 are provided at both ends of the microchannels 92 and 93, respectively, and upper portions of the pods 94 to 97 are open. Its size is a rectangle of about 15 mm × 20 mm to 20 mm × 30 mm.
The sensor chip 9 is placed on the measurement stage 1 as shown in FIG. The sensor chip mounting table 16 of the measurement stage 1 is provided with a recess 16a that is slightly larger than the outer shape of the sensor chip 9, and the sensor chip 9 is positioned and inserted therein. The positioning member is not shown.

The chip cover 17 is arranged at a predetermined distance above the sensor chip 9 below the movable table 12, and fits the sensor chip 9 from above the positioned sensor chip 9 as shown in FIG. The sensor chip 9 is lowered and covered.
The chip cover 17 is formed at both end portions so that an input port 17a and an output port 17c each having a crank-shaped communication path correspond to the position of the upper portion of the microchannel 92, as indicated by a dotted line. Similarly, the input port 17b and the output port 17d are formed at both ends so as to correspond to the position of the upper portion of the microchannel 93. However, in the side view of FIG. 3, the input ports 17a and 17b are viewed from the side. Since the positions overlap and have the same shape, only the input port 17a on the microchannel 92 side in FIG. 2A is indicated by a dotted line, and the input port 17b is omitted.
The openings of the input ports 17a and 17b are positioned corresponding to the positions of the pods 94 and 96 of the sensor chip 9 positioned on the sensor chip mounting table 16, and the openings of the output ports 17c and 17d are similarly pods 95. , 97 are positioned so as to correspond to the positions.
The chip cover 17 may be made of PDMS or SUS, and other members that do not affect the measurement may be used.

The input ports 17a and 17b and the output ports 17c and 17d are provided with trumpet-shaped connector insertion portions 18 at both end portions of the chip cover 17, respectively. Each input / output port is connected to the injectors 21 and 22 via the connector insertion portion 18 by a conduit.
Thereby, the pods 94 and 96 are connected to the injectors 21 and 22 shown in FIG. 1, respectively, and supply of a predetermined amount of the chemical solution from the input ports 17a and 17b respectively to the pods 94 and 96 is filled in the pods 94 and 96. The The supplied chemical solution further flows into the microchannels 92 and 93, and is sent to the pods 95 and 97 through these. Furthermore, it is discharged from the output ports 17c and 17d through these pods and sent to the waste liquid holder 28 through the conduit.

As shown by a dotted line in FIG. 2B, a seal ring projection 19 is provided on the chip cover 17 so as to protrude downward as a flange corresponding to the positions of the pods 94 to 97. Thereby, the chemical | medical solution (liquid feeding) sent from the injectors 21 and 22 and the chemical | medical solution (liquid feeding) discharged | emitted do not leak.
The chip cover 17 is configured to be pressed against the surface of the sensor chip 9 with a constant pressure, but the pressing mechanism is not shown.
As shown in FIG. 2A, the chip cover 17 is provided with holes 17e and 17f. These holes 17e and 17f are rectangular holes located above the microchannels 92 and 93, respectively, as indicated by a one-dot chain line in FIG. Two bundle tubes 40a and 40b (see FIG. 3) are inserted into the holes 17e and 17f, respectively. In FIG. 1, the two bundle pipes 40a and 40b are shown in parallel with two positions shifted for convenience of explanation, but in reality, they are overlapped in the front and rear. The bundle tube 40b is overlapped with the bundle tube 40a, and only the bundle tube 40a side is shown.

The light projecting optical fiber and the light receiving optical fiber are formed as one bundle tube 40a, 40b of about 2 mmφ as shown in FIG. 6C at the tip portion facing the sensor chip 9, and the bundle tube 40a, 40b is fixedly supported by penetrating through the hole of the movable table 12 as shown in FIG. As a result, the tip ends of the bundle pipes 40a and 40b are arranged in the holes 17e and 17f, respectively. The position of each tip is located above the microchannels 92 and 93, respectively.
2B, the pods 94 to 97 and the microchannels 92 and 93 are respectively formed with the optical thin film sensor unit 100 on the surface of the silicon nitride (SiN) optical thin film 9b. Here, the optical thin film sensor unit 100 is formed by storing a buffer solution containing a ligand in the buffer solution holder 25 and sending the buffer solution from the input ports 17a and 17b of the sensor chip 9 to the pods 94 and 96. This is performed by filling it and flowing it through the microchannels 92 and 93, respectively.
The optical thin film 9b is made of SiN, SiN + amino group, SiN + epoxy group, SiN + carboxyl group or the like, and the optical thin film sensor unit 100 is made of a ligand attached to the surface of the optical thin film 9b. After the optical thin film sensor unit 100 is formed, the sensor chip 9 is provided as each sensor chip.
In the following description, it is assumed that the optical thin film sensor unit 100 is already formed in each of the pods 94 to 97 and the microchannels 92 and 93.

Returning to FIG. 1, the liquid feeding system 2 is controlled by the data processing / control device 7 and includes injectors 21 and 22, pumps 23 and 24, buffer liquid holder 25, pump control units 26 and 27, and a waste liquid holder 28. .
The pump control units 26 and 27 respectively drive the pumps 23 and 24 to suck a predetermined amount of the chemical solution from the buffer solution holder 25 and supply the chemical solution to the injectors 21 and 22 through the conduits connected to the respective pump control units 26 and 27.
The injectors 21 and 22 supply a predetermined amount of the chemical solution adjusted to the pods 94 and 95 through the conduits connected to the input ports 17a and 17b.
The temperature adjustment system 3 includes a constant temperature base 11 and a temperature control unit 31, and sets and controls the temperature of the constant temperature base 11 so that the sensor chip 9 reaches a target temperature under the control of the data processing / control device 7.

The light projecting system 4 includes a light source 41 of a halogen lamp and two optical fiber bundles 42 and 43, and irradiates light from the light source 41 to the microchannels 92 and 93 of the sensor chip 9.
The optical fiber bundles 42 and 43 are light projecting optical fibers composed of six optical fibers 44 as shown in FIG. At the position of the light output of the light source 41, as shown in FIG. 6A, the six optical fibers 44 of the optical fiber bundles 42 and 43 are arranged in two stages and arranged vertically. The diameter of each optical fiber is 0.5 mmφ.
The paths of these optical fiber bundles 42 and 43 are cut off halfway and separated into two blocks 42a and 42b and 43a and 43b, respectively.
Between the two blocks 42a, 42b and 43a, 43b, a two-channel light projecting fiber switching mechanism 45 is provided. As a result, switching is performed to block one of the light projected to the microchannels 92 and 93 of the sensor chip 9 and transmit the other. For the switching, the drive signal from the data processing / control device 7 is received by the solenoid drive circuit 46 via the USB interface 73 and the USB hub 8 and the projection switching signal S1 (see FIG. 10A) is sent to the shutter mechanism 47. This is done by driving.

FIG. 4 is a front view of the two-channel light projecting fiber switching mechanism. The shutter mechanism 47 has brackets 47b and 47c erected at both ends of the base plate 47a, and solenoids 48a and 48b fixed to the brackets 47ba and 47c are provided at both ends, respectively. A shutter plate 49 is bridged and attached to each of the solenoids 48a and 48b with a rod that advances and retreats. Reference numeral 49a denotes an insertion and fixing plate for the optical fiber bundles 42 and 43, and a similar one is provided on the near side, but is not visible in the figure. The insertion fixing plate 49a is erected and fixed to the base plate 47a, and an optical fiber holding connector is inserted into each as shown in FIG.
The two insertion / fixation plates respectively before and after the shutter plate 49 are arranged so that the optical fiber centers of the two blocks 42a and 42b and the two blocks 43a and 43b that are separated coincide with each other. Each optical fiber is fixed.
In FIG. 4, the shutter mechanism 47 has the base plate 47a positioned on the lower side. However, the shutter mechanism 47 may be reversed and used with the base plate 47a positioned on the upper side.

The shutter plate 49 has one hole 50 for light transmission. When one of the solenoids 48a and 48b is driven by the solenoid drive circuit 46, the hole 50 is positioned corresponding to one of the positions of the optical fiber bundles 42 and 43 as shown in FIG. The projector is designed to allow light to pass through. The diameter of the hole 50 is slightly larger than the diameter 2 mmφ of the optical fiber bundles 42 and 43 and is about 3 mmφ.
The light receiving system 5 includes optical fibers 51 and 52 and a spectroscope 53. As shown in FIG. 6C, the optical fibers 51 and 52 are optical fibers in which the distal end side serving as a light receiving portion is arranged at the center of the six optical fibers 44 of the bundle pipes 40a and 40b, and from there This is shown as one optical fiber 51 (52) on the right side as drawn out through each bundle tube 40a, 40b.

As shown in FIG. 1, the spectroscope 53 is a transmission diffraction grating type spectroscope, and has an input connector 53a. As shown in FIG. 5, the slit 54 receives incident light through the input connector 53a. And a collimator mirror 55, a transmissive holographic grating 56, a focusing mirror 57, a one-dimensional CCD image sensor (linear sensor) 58, and the like.
Two optical fibers 51 and 52 are provided in the slit 54 along the longitudinal direction of the slit 54 via an input connector 53a. The width of the slit 54 that receives the incident light is slightly larger than the diameter of the optical fiber 0.5 mmφ, the length is several mm, and a plurality of optical fibers can be arranged along the longitudinal direction of the slit 54. . Therefore, in the transmissive holographic grating 56, when viewed from the horizontal plane, the irradiation light of the optical fibers 51 and 52 is at the same position, and the light from each fiber is irradiated in the vertical direction while being shifted up and down.
The light incident from the slit 54 undergoes wavelength analysis through the collimator mirror 55, the transmission holographic grating 56, and the focusing mirror 57, and the spectral light enters the CCD sensor 58 at a reflection angle corresponding to each wavelength from the focusing mirror 57. Is done. Here, the CCD sensor 58 has a number of pixels of 1024, and the pixel width in the direction perpendicular to the pixel arrangement direction receives the spectral light obtained by analyzing the incident light of the two optical fibers 51 and 52 arranged above and below. It is large enough to be able to.

Returning to FIG. 1, the light reception control circuit 6 includes a controller 61, an A / D conversion circuit (A / D) 62, a memory 63, and a USB interface 64.
The controller 61 reads 1024 pixels obtained from the CCD sensor 58 of the spectroscope 53 in accordance with a control signal from the data processing / control device 7, and converts the output signal into a digital value by, for example, a 16-bit A / D 62. Then, a process of storing in the memory 63 corresponding to the detected pixel position is performed.
Each detection pixel position corresponds to the wavelength of the analyzed spectrum waveform, and the controller 61 receives the spectrum start signal AS (see FIG. 10 (c)) from the MPU 71 and is A / D converted. One spectrum analysis data is read from the CCD sensor 58 via the A / D 62 and stored in the memory 63. When the storage is completed, an interrupt signal In (see FIG. 10 (d)) is generated in the data processing / control device 7. Of course, in this case, reading of the spectral analysis data for one time may be performed a plurality of times, for example, about 100 times, and 100 pieces of spectral analysis data may be stored in the memory 63. The spectrum analysis data is read from the CCD sensor 58 by the controller 61 after a predetermined time from the switching timing (rising or falling) of the projection switching signal S1 (see FIG. 10A), for example, 1.1 sec. Done later.

The USB interface 64 performs a process of transferring the received light data (one time or a plurality of times of spectrum analysis data) stored in the memory 63 to the data processing / control device 7 in accordance with the control of the data processing / control device 7.
The data processing / control device 7 is a normal personal computer having a USB terminal. This has an MPU 71, a memory 72, a USB interface 73, a display 74, a keyboard 75, and a bus 76 for connecting them. The measurement data (spectrum analysis data) stored in the memory 63 in response to the interrupt signal In from the controller 61 is obtained via the USB interface 64 and the USB interface 73 and stored in a predetermined area of the memory 72. Reference numeral 77 denotes an external storage device such as an HDD.

  The memory 72 stores a time division switching program 72a, a measurement data collection program 72b, an interference spectrum waveform calculation / display program 72c, a peak shift calculation / display program 72d, and the like, and is provided with a parameter area 72e and a work area 72f. It has been. The time division switching program 72a is called and executed by the MPU 71 in response to a function key input for starting measurement on the keyboard 75 or during execution of another program. This is executed by the MPU 71, and the MPU 71 drives the two-channel light projecting fiber switching mechanism 45, for example, at intervals of 1.5 seconds (see the light projecting switching signal S 1 in FIG. 10A). The irradiation light of the optical fiber bundle 41 and the optical fiber bundle 42 is controlled by alternately switching the projection light from the fiber bundle 41 and the optical fiber bundle 42 and irradiating the microchannels 92 and 94 of the sensor chip 9 alternately. Spectral analysis data obtained from the spectroscope 53 corresponding to each period, for example, 100 pieces of analysis data is stored in the memory 63 of the light reception control circuit 6.

  The measurement data collection program 72b is called and executed by the MPU 71 in response to a predetermined function key input on the keyboard 75 or during execution of another program. The MPU 71 executes this, and the MPU 71 drives the liquid feeding system 2 by the data processing / control device 7. Initially, the buffer solution for diluting the sample is accumulated in the buffer solution holder 25. The execution of this program at this time causes the buffer solution to flow through the microchannel 92 (first channel) and the microchannel 93 (second channel). At the same time, the time division switching program 72a is called and executed by task processing. Then, in response to the interrupt signal In generated from the controller 61 after a predetermined time from the timing of switching the light projection switching signal S1 (see FIG. 10 (a)) of the light projecting fiber switching mechanism 45, the data read signal Rd. (See FIG. 10 (d)) is sent to the controller 61. As a result, the microchannels 92 (corresponding to the first channel), 94 (corresponding to the second channel) from the memory 63 of the light receiving control circuit 6 are alternately switched every time the light projecting fiber switching mechanism 45 is switched by the light projecting switching signal S1. 100 spectral analysis data (measurement data) of the reflected light are alternately read out via the USB interface 64 and stored in the memory 72. At this time, the read spectrum data of the reflected light of each optical thin film sensor unit 100 is stored in the storage position corresponding to each channel in the work area 72f. Then, the MPU 71 calls the interference spectrum waveform calculation / display program program 72c.

The interference spectrum waveform calculation / display program program 72c is called by the MPU 71 in response to the function key input of the spectrum waveform data display on the keyboard 75 in addition to the call at the end of the execution of the measurement data collection program 72b. . This is executed by the MPU 71, and the MPU 71 has a total of 200 spectra of 100 each corresponding to the analysis wavelengths of the microchannel 92 (first channel) and the microchannel 93 (second channel) stored in the work area 72 f. Waveform data is created by averaging the data, and an interference spell waveform as shown in FIG. 7A is displayed on the display 74 with the received light level [voltage] as the vertical axis and the wavelength as the horizontal axis.
The interference spell waveform at this time is an interference spell waveform for the ligand because it is measured by sending a buffer solution for diluting the sample. When the difference D between the peaks and valleys of the interference spell waveform is small, the tip of the optical fiber is separated from the tip surface or pushed into the tip surface. Adjust the position and display the interference spell waveform again to check whether it is appropriate.

The peak shift calculation / display program 72d is called and executed by the MPU 71 in response to a function key input for starting measurement or a predetermined function key input when the interference spell waveform is appropriate. At this time, the buffer solution holder 25 is filled with the sample in the buffer solution.
The MPU 71 executes this program and starts measuring a sample. The MPU 71 controls the liquid delivery system 2, injects samples from the injectors 21 and 22 into the pods 94 and 95, calls the time division switching program 72a and the measurement data collection program 72b, and performs task processing in parallel. Perform these. As a result, a predetermined amount of chemical liquid adjusted to a predetermined speed is caused to flow through the microchannels 92 (first channel) and 94 (second channel) to form the microchannels 92 (first channel) and 94 (second channel). The spectral data of the reflected light from each optical thin film sensor unit 100 is stored in the work area 72f of the memory 72 for each channel. At this time, the interference spectrum waveform calculation / display program program 72c is not called.

Further, the MPU 71 calculates the wavelength of the wavelength λp at the position of the peak of each channel (the valley of the reflected light) based on the spectrum data (200 pieces) corresponding to each channel stored in the work area 72f of the memory 72 obtained with time. The amount of change is calculated.
Specifically, the MPU 71 averages a large number of spectrum data of the first channel and the second channel stored in the work area 72f at a measurement time of 3 seconds every 1.5 seconds. Then, a Forked function coefficient is calculated by the least square method, and each spectral waveform data is subjected to a fitting process by the Forked function to detect the wavelength λp of the peak position (see FIG. 7A). Furthermore, by calculating the wavelength difference Δλ = λpi-λpo from each spectral waveform data wavelength λpi (where λpo is the wavelength λp at the peak position at the start of measurement), the amount of change in wavelength versus time data is created, and the change in wavelength A peak shift waveform as shown in FIG. 7B is displayed on the display 74 with the amount Δλ as the vertical axis and the elapsed time as the horizontal axis.
The flowchart of each program process described above is omitted because each program process is simple and seems to be understood from the above description.

FIG. 8 is an explanatory view of an 8-channel light projecting fiber switching mechanism. The 8-channel light projecting fiber switching mechanism is provided with a shutter plate 49 of the shutter mechanism 47 of the light projecting fiber switching mechanism 45 in FIG. This is a rotary shutter disk 49a. As shown by a solid line and a dotted line, the light projecting fiber switching mechanism 45a is configured to send eight light projecting optical fiber bundle lights 41a to 41h at eight positions on the outer periphery of the disk at intervals of 45 degrees, as shown in FIG. Instead of the projecting optical fiber bundle lights 41 and 42, they are arranged in a circle. A light transmitting hole 50 is provided at one location on the outer periphery of the shutter disk 49a. The light projecting fiber switching mechanism 45a is configured to step-feed the shutter disk 49a in units of 45 degrees by the stepping motor 50a to select one irradiation light of the eight channel light projecting optical fiber bundle lights 41a to 41h. One of the microchannels of the sensor chip on which the microchannel of the channel is formed is selectively irradiated.
As a result, it is possible to perform measurement by wavelength analysis using one spectrometer in a time division manner for each microchannel of the 8-channel sensor chip.
In this case, the light receiving system 5 has eight light receiving system optical fibers. Therefore, the spectroscope 53 arranges eight light receiving system optical fibers in the slit 54 along the longitudinal direction of the slit 54, and sets the width of one pixel of the CCD sensor in the direction orthogonal to the pixel array to eight light receiving systems. What is necessary is just to make it the magnitude | size which can receive the light from an optical fiber.

FIG. 9 is a plan view of a light receiving system fiber switching mechanism, a light receiving system fiber layout diagram, and a spectrometer side fiber layout diagram of the light receiving system fiber switching mechanism in another embodiment to which the present invention is applied. Except for the light receiving fiber switching mechanism and the spectroscope, other configurations of this embodiment are the same as those shown in FIG.
As shown in the plan view of FIG. 9A, the fiber switching mechanism 400 of the light receiving system includes an X-axis moving mechanism 402 provided on a base 401, an optical connector 403, and an input side optical fiber for inputting to a spectrometer. 404 (hereinafter referred to as an optical fiber 404), a movement reference position 405 provided on the base 401, and a motor drive circuit 406.
The optical connector 403 includes a fixed-side optical fiber connector portion 403a and a movable-side optical fiber connector portion 403b.

The X-axis moving mechanism 402 includes a ball screw mechanism 402a, its moving table 402b, and a stepping motor 402c. The moving table 402b is equipped with a movable-side optical fiber connector 403b, and the moving reference position 405 has a reference position detection. A photo interrupter 405a is provided as a device.
In the ball screw mechanism 402a, the screw shaft is rotationally driven by a stepping motor 402c. The stepping motor 402c is provided with an encoder 402d for detecting the amount of movement of the moving base 402b. The stepping motor 402c is driven by the motor drive circuit 406. Is done.
The output signal of the encoder 402d and the detection signal of the photo interrupter 405a are input to the data processing / control device 7 via the lead wires 407a and 407b and the USB hub 8, respectively. The motor drive circuit 406 is connected to the data processing / control device 7 via the lead wire 407 c and the USB hub 8.

As shown in the light receiving system fiber arrangement diagram of FIG. 9B, the fixed side optical fiber connector portion 403a is fixed on the base 401, and the light output side end portions of the optical fibers 51 and 52 (two light receiving system fibers). Are mounted and fixed at predetermined intervals. On the other hand, as shown in the spectroscope-side fiber arrangement diagram of FIG. 9C, the movable-side optical fiber connector 403b fixes the light-incident side end of the spectroscope-side optical fiber 404 in the X-axis direction. Moving. The end of the light exit side of the optical fiber 404 is coupled to the spectroscope 59 at the light incident port so that the received light enters the spectroscope 59.
Unlike the above-described spectroscope 53, the spectroscope 59 has a light incident port of one optical fiber, and is a reflective or transmissive diffraction grating provided with an input connector 59a that enters the light incident port. It is a normal spectroscope having This outputs a spectrum analysis signal to the A / D 62 as with the spectroscope 53.

The light receiving system fiber switching mechanism 400 is switched according to the switching of the light projecting system fiber switching mechanism 45 under the control of the MPU 71 by the MPU 71 executing a light receiving system fiber switching switching program (not shown) provided in the memory 72. Done. Thereby, either the optical fiber 51 or the optical fiber 52 is selectively optically coupled to the optical fiber 404.
In the parameter area 72e, the moving distance of each moving base 402b from the moving reference position 405 to the optical fiber 51 and the optical fiber 52 is stored as the number of drive pulses of the stepping motor 402b.
The movement distances to the optical fiber 51 and the optical fiber 52 stored in the parameter area 72e are measured as follows.

First, in the biochemical measurement apparatus 10, the stepping motor 402 b is driven to receive the detection signal from the photo interrupter 405 a and the moving base 402 b is set to the movement reference position 405. Next, the light projecting fiber switching mechanism 45 is driven to turn the microchannel 92 (first channel) into the light irradiation state, and the stepping motor 402b is driven from the movement reference position 405 to move the moving table 405 to the optical fiber 51. The number of drive pulses from the movement reference position 405 when the detection output of the spectroscope 59 becomes maximum is stored in the parameter area 72e. Next, the number of drive pulses is stored in the parameter area 72e in the same manner for the microchannel 93 (second channel).
Here, the position at which the detection output of the spectroscope 59 reaches the maximum is that the centers of the optical fibers that are optically coupled coincide with each other.
The switching of the received light of the microchannel 92 and the microchannel 93 here is not a direct switching from the microchannel 92 to the microchannel 93 or vice versa, but after the moving base 402b is once returned to the movement reference position 405. The moving base 402b is moved to the microchannel 92 or the microchannel 93 with the movement reference position 405 as a reference. By performing such switching, it is possible to eliminate the accumulated positioning error regarding the optical coupling between the optical fiber 404 and the optical fiber 51 or 52.

FIG. 10 is an explanatory diagram of the switching timing of the light projecting fiber switching mechanism and the light receiving fiber switching mechanism.
FIG. 10A shows a light projection switching signal S1, and the solenoid drive circuit 46 receives this signal and drives the shutter mechanism 47 with the rising and falling edges of the light projection switching signal S1 as the respective switching timings. Thereby, when the projection switching signal S1 is at a high level (“H”), the projection to the microchannel 92 is selected, and when the projection switching signal S1 is at a low level (“L”), the projection to the microchannel 93 is performed. Is selected. The cycle of the light projection switching signal S1 is 3 seconds, and the light projection period for each channel is 1.5 seconds.
FIG. 10B shows a light reception switching signal S2. The rising and falling edges of this signal are used as the switching timings to drive the stepping motor 402b to return the moving base 402b to the movement reference position 405, from which the stepping motor 402b The optical fiber 51 or the optical fiber 52 and the optical fiber 404 are optically coupled by driving a predetermined number of pulses. The cycle is the same as the light projection switching signal S1. When the light reception switching signal S2 is “H”, the light reception of the reflected light from the microchannel 92 is selected, and when the light reception switching signal S2 is “L”, the light projection to the microchannel 93 is selected.
The time for setting the optical fiber 404 for optical coupling from the rise or fall of the light reception switching signal S2 is about 0.2 seconds. A spectral start signal AS shown in FIG. 10C is generated in accordance with the timing when the movement of the moving table 402b for optical coupling is completed.

FIG. 10D shows an interrupt signal In from the controller 61 indicating the completion of spectroscopy. The reason why this interrupt signal is indicated by a dotted line is that since the spectral processing time is usually only about 0.2, this interrupt signal is not necessarily required for control.
FIG. 10E shows a data read signal Rd. The data read signal Rd corresponds to the interrupt signal In from the controller 61 or after the elapse of a predetermined time from the rise or fall of the projection switching signal S1, for example, 1.1 seconds later, the data is sent from the data processing / control device 7 to the controller 61. The MPU 71 reads the spectrum data DS (see FIG. 10F) from the memory 63 at the falling timing of the data read signal Rd.

  By the way, in this embodiment, the two light receiving system optical fibers are switched corresponding to the embodiment of FIG. 1, but the eight channels of the light receiving system fiber as shown in FIG. The light-receiving optical fiber can be configured by a similar rotary shutter disk so that eight channels can be switched.

As described above, the light projecting optical fiber according to the embodiment is provided with a plurality of fibers in one bundle, and one light receiving optical fiber is provided for this. The optical system optical fiber may be one instead of the bundle, and conversely, a plurality of light receiving system optical fibers may be provided in one bundle.
The light projecting fiber switching mechanism of the embodiment switches the irradiation light of the optical fiber bundle 41 (corresponding to the first channel) and the optical fiber bundle 42 (corresponding to the second channel) alternately at intervals of 1.5 seconds. The measurement data is obtained from one spectroscope. However, this switching interval is not limited to the 1.5 second interval. Further, in this case, the present invention is not alternating. For example, the optical fiber bundle 41 (first channel) is first selected to obtain a plurality of waveform data, and then the optical fiber bundle 42 (second channel). The switching may be performed once such that a plurality of waveform data is obtained in the same manner.
In the embodiment, the optical thin film sensor unit is provided with each pod communicating with each microchannel on both sides, but a plurality of optical thin film sensor units may be provided separately in one channel. Of course.

FIG. 1 is a block diagram of a biochemical measuring apparatus according to an embodiment to which the present invention is applied. 2A is an explanatory plan view of a sensor chip in which two microchannels are formed, and FIG. 2B is an AA cross-sectional explanatory view thereof. FIG. 3 is an explanatory diagram of an explanatory diagram of the measurement stage. FIG. 4 is a front view of a two-channel light projecting fiber switching mechanism. FIG. 5 is an explanatory view of the arrangement of the light receiving system optical fibers in the light incident side slits of the optical fiber and the diffraction grating type spectrometer. FIG. 6 is a cross-sectional explanatory view of the optical fiber bundle of the light projecting system and the light receiving system. FIG. 7 is an explanatory diagram of the measured interference spectrum and the mobility (peak shift graph) of the valley of the reflected light. FIG. 8 is an explanatory view of an 8-channel light projecting fiber switching mechanism. FIG. 9A is a plan view of a light receiving fiber switching mechanism in another embodiment to which the present invention is applied, FIG. 9B is a light receiving fiber arrangement of the light receiving fiber switching mechanism, and FIG. ) Is a fiber arrangement diagram of the spectrometer side of the light receiving system fiber switching mechanism. FIG. 10 is an explanatory diagram of the switching timing of the light projecting fiber switching mechanism and the light receiving fiber switching mechanism.

Explanation of symbols

1 ... Measurement stage,
2 ... Liquid feeding system, 3 ... Temperature control system,
4 ... Light projecting system, 5 ... Light receiving system, 6 ... Light receiving control circuit,
7 ... Data processing / control device, 8 ... USB bubbling,
9 ... Sensor chip, 10 ... Biochemical measuring device,
11 ... Constant temperature base, 12 ... Moving table, 12a ... Adjusting knob,
13 ... Base of device, 14 ... Bracket, 15 ... Abutting stopper bar,
16 ... Sensor chip mounting table, 17 ... Chip cover,
17a, 17b ... input ports,
17c, 17d ... output ports, 21, 22 ... ejectors,
23, 24 ... pump, 25 ... buffer solution holder,
26, 27 ... Pump control unit, 28 ... Waste liquid holder,
40a, 40b ... bundle tube, 41 ... halogen lamp light source,
42, 43 ... optical fiber bundles,
44 ... Optical fiber, 45 ... Projection fiber switching mechanism,
46 ... Solenoid drive circuit, 47 ... Shutter mechanism,
48a, 48b ... solenoids, 49 ... shutter plates,
72a ... time-division switching program,
72b ... measurement data collection program,
72c ... Interference spectrum waveform calculation / display program,
72d ... Peak shift calculation / display program,
72e ... parameter area, 72f ... work area,
92, 93 ... microchannel, 94-97 ... pod,
400: fiber switching mechanism of light receiving system, 401: base,
402 ... X-axis moving mechanism, 403 ... Optical connector, 404 ... Input side optical fiber,
405: Movement reference position, 406: Motor drive circuit.

Claims (12)

In a biochemical measuring device that measures the binding of biochemical substances using the optical interference of optical thin films,
a sensor chip having n (n is an integer of 2 or more) optical thin film sensor units;
N light projecting optical fibers that respectively irradiate light to the n optical thin film sensor units;
A light projecting fiber switching mechanism which is provided in the middle of the n light projecting optical fibers and selectively passes the light projecting from one of the n optical fibers and blocks the remaining light projecting; ,
N light receiving optical fibers for receiving the reflected lights from the n optical thin film sensor units,
A spectroscope that receives the reflected light from the n light receiving optical fibers in common on the light incident side;
A control unit that controls the light projecting fiber switching mechanism to control the irradiation light from any one of the light projecting optical fibers;
A biochemical measurement apparatus for spectroscopically analyzing the reflected light from the optical thin film sensor unit irradiated by the selected light projecting optical fiber. The sensor chip is an n-channel sensor chip in which n microchannels are formed and the optical thin film sensor unit is provided for each channel, and includes one light projecting optical fiber and one light receiving optical fiber. Is arranged corresponding to one of the microchannels, the control unit is configured to switch and control the light projecting fiber switching mechanism in a time-sharing manner,
The biochemical measurement apparatus according to claim 1, wherein a signal regarding a wavelength obtained by spectrally separating the reflected light from the spectroscope is obtained in a time division manner corresponding to each of the n channels.   Each of the n microchannels has pods formed at both ends thereof, and the entire pod and each of the microchannels are optical thin film sensor units, and the pods at both ends are respectively input for liquid feeding. The biochemical measurement device according to claim 2, which is coupled to the port and the output port.   Further, the sensor chip has a liquid feeding device for feeding a biochemical substance serving as a probe to n microchannels of the sensor chip, the sensor chip has an optical thin film in which a metal thin film is formed on a substrate, and the n optical channels The biochemical measurement apparatus according to claim 3, wherein the thin film sensor unit is formed on the optical thin film by feeding the biochemical substance to the sensor chip via the pod.   Each of the light projecting optical fibers is configured as a bundle composed of a plurality of optical fibers, and the tip of each of the n pieces of bundles is arranged above each of the n pieces of optical thin film sensor units, and n pieces 5. The biochemical measurement according to claim 4, wherein each of the light receiving system optical fibers is composed of one optical fiber, and a light receiving portion thereof is disposed at a central portion of the bundle at the tip of each of the n bundles. apparatus.   The spectroscope is a spectroscope having a transmission diffraction grating and a large number of light receiving elements arranged in a spectrum analysis direction, and the n light receiving system optical fibers have a diameter at the light entrance of the spectroscope. The width of the slit is smaller than this, and is arranged along the direction of the length of the slit, and the light receiving element receives the spectrum analysis light of light incident from the n light receiving system optical fibers. The biochemical measurement apparatus according to claim 4, wherein the biochemical measurement apparatus has a predetermined width in a direction orthogonal to the direction of the arranged light receiving elements.   Further, light received from one optical fiber among the n light receiving optical fibers is selected, and the received light is incident on one optical fiber, and the light output from the one optical fiber is changed to the light output from the one optical fiber. The biochemical measurement apparatus according to claim 4, further comprising a light receiving system fiber switching mechanism that inputs to the spectroscope.   The light receiving system fiber switching mechanism includes: a first connector member that fixes a light output side end of the n light receiving system optical fibers; and a light incident side end of an input side optical fiber that inputs to the spectrometer. An optical connector comprising a second connector member for fixing the first connector member, the first connector member as a fixed side, the second connector member being movable, and one of the n light receiving optical fibers, The biochemical measurement device according to claim 7, wherein the input side optical fiber is selectively optically coupled.   The light receiving system fiber switching mechanism further includes a uniaxial moving mechanism for moving the second connector member, and the uniaxial moving mechanism has a reference position, and the second connector member is used as the reference member. The biochemical measurement apparatus according to claim 8, wherein the optical coupling is performed by moving from a position.   The sensor chip substrate is a silicon substrate, and the optical thin film is formed by depositing silicon nitride on the surface of the silicon substrate, and has a light-transmitting property having the n microchannels with respect to the silicon substrate. The biochemical measurement apparatus according to claim 5, wherein the sensor chip is formed by bonding a facing substrate made of silicone rubber.   An adjustment mechanism that adjusts the distance of the position of the tip of each bundle with respect to each of the optical thin film sensor portions of the sensor chip at the top of each of the n optical thin film sensor portions. The position of the tip of each bundle is adjusted by the adjustment mechanism according to the waveform of the interference spectrum obtained in response to the signal about the spectral wavelength obtained from the spectroscope when the buffer solution to be diluted is sent. Item 10. The biochemical measurement apparatus according to Item 10.   Further, a chip cover having the input port and the output port is provided on the sensor chip, the chip cover has the input port and the output port, and the chip cover is placed on the sensor chip. 12. The biochemical measurement apparatus according to claim 11, wherein the input port and the output port sometimes communicate with the pods at both ends.

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