Fluorescence detector for flow cytometry
By designing a fluorescence detector including SiPM unit, adjustable power supply unit and filtered AD conversion unit, the problems of fluorescence intensity and complexity and cost of detector systems in traditional flow cytometry analyzers are solved, and the detection effect of high gain, low power consumption and small volume is achieved.
Patent Information
- Application Number
- CN202422170581.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-05
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-09-05
AI Technical Summary
In traditional flow cytometry analyzers, the fluorescence light excitation by a single cell is extremely weak, which makes the detector system complex and costly, and it is difficult for suppliers to flexibly debug.
A fluorescence detector including a SiPM unit, an adjustable power supply unit and a filtered AD conversion unit is designed, and a high gain, low power consumption and small volume fluorescence detection is achieved using a SiPM chip, a transimpedance amplifier TIA, a regulation resistor and a matching capacitor, combined with an AD chip and an amplifier.
The fluorescence detection effect with high gain, low power consumption, small size, low operating voltage, and insensitive to magnetic fields is achieved, solving the problems of complexity and high cost of traditional detector systems.
Smart Images
Figure CN223021871U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a flow cytometer, in particular to a fluorescence detector for a flow cytometer. Background Art
[0002] A silicon photomultiplier (SiPM) is a solid-state semiconductor device based on a silicon substrate, with photon energy level sensitivity and a dynamic range of 7.2 orders of magnitude. The SiPM is a compact detector with photon counting function, consisting of an array of avalanche photodiodes with a compact design and capable of operating simultaneously. Cells are arranged neatly and pass through the laser detection area one by one under laser irradiation. The method to achieve this is the "flow cytometry technique" (also known as the "sheath flow technique"), that is, in the sheath flow chamber, the "blood sample" to be detected is "liquid focused" by the sheath fluid, so that the sample to be measured forms a liquid flow with a diameter approximately the size of a cell, and the cells pass through the laser irradiation area regularly one by one for detection.
[0003] In traditional flow cytometers, since the fluorescence intensity excited by a single cell is extremely weak, generally in the design, a photomultiplier tube (PMT) or an avalanche diode (APD) is used to convert the optical signal into an electrical signal. The photomultiplier tube has many advantages, but its disadvantages are also obvious - large volume, requiring a high-voltage power supply circuit of hundreds or thousands of volts, and the system design is relatively complex. Summary of the Utility Model
[0004] The purpose of the utility model is to provide a fluorescence detector for a flow cytometer, which solves the problems that the detector system cannot be flexibly debugged by suppliers and has a relatively high cost.
[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0006] A fluorescence detector for a flow cytometer, comprising an SiPM unit, an adjustable power supply unit, and a filtering AD conversion unit, wherein:
[0007] The SiPM unit includes an SiPM chip, a transimpedance amplifier TIA, an adjusting resistor R F and a matching capacitor C F , the bias terminal of the SiPM chip is connected to the AOUT output terminal of the transimpedance amplifier TIA to output a negative pulse, and the two pins of the adjusting resistor R F and the matching capacitor C F are connected in parallel to the input terminal and the output terminal of the transimpedance amplifier TIA;
[0008] The adjustable power supply unit includes rated resistors C68, C69, C70, C71, C53, C54, and C5 connected in parallel to pins 2, 6, 5, and 4 of the voltage regulator Z1 in sequence. Pins 1 and 3 of the voltage regulator Z1 are connected to the input pins of the SiPM chip;
[0009] The AD conversion unit is connected to the Vout of the SiPM unit and includes an AD chip and a U6AD module. The input end of the AD chip is data-connected to the output end of the U6AD module.
[0010] Preferably, the SiPM chip is TP3050, with a gain of 2.5*10 6 , a spectral range of 250 - 950 nm, a mainstream single-laser flow cytometry band of 488, and a mainstream FITC staining fluorescence range from 500 - 820 nm.
[0011] Preferably, the adjustment resistor R F under the operation of the SiPM chip is 910 Ω, and the matching capacitor C F is 0.5 pF.
[0012] Preferably, the model of the AD chip is LTC2310CMSE - 14, with a sampling rate of 2.2 MSPS and a resolution of 14 bits.
[0013] Preferably, the AD conversion unit further includes an amplifier U5. A first circuit branch in which a rated resistor R24, a rated resistor R25, and a capacitor C10 are connected in parallel is connected in series between pins 3 and 4 of the amplifier U5;
[0014] Pin 6 of the amplifier U5 is connected to pin 6 of the U6AD module, and a rated resistor R27 is connected in series in the connection circuit between the two.
[0015] Preferably, a capacitor C13 is connected in parallel between pin 7 of the U6AD module and the connection between the rated resistor R27 and pin 6 of the U6AD module.
[0016] In the above technical solution, a fluorescence detector for a flow cytometer provided by the present utility model has the following beneficial effects: It has the advantages of high gain, low power consumption, small volume, low working voltage, and insensitivity to magnetic fields. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.
[0018] Figure 1 It is the circuit diagram of the SIPM unit provided by the embodiment of the present utility model;
[0019] Figure 2 It is the circuit diagram of the adjustable power supply unit provided by the embodiment of the present utility model;
[0020] Figure 3 It is the circuit diagram of the filtering AD conversion unit provided by the embodiment of the present utility model. Detailed implementation manners
[0021] To enable those skilled in the art to better understand the technical solutions of the present utility model, the following will further introduce the present utility model in detail in conjunction with the drawings.
[0022] As Figures 1-3 shown, a fluorescence detector for a flow cytometer includes a SiPM unit, an adjustable power supply unit, and a filtering AD conversion unit, wherein:
[0023] Combined with Figure 1 it can be known that the SiPM unit includes a SiPM chip, a transimpedance amplifier TIA, a regulating resistor R F and a matching capacitor C F , the bias terminal of the SiPM chip is connected to the AOUT output terminal of the transimpedance amplifier TIA to output a negative pulse, and the two pins of the regulating resistor R F and the matching capacitor C F are connected in parallel to the input terminal and the output terminal of the transimpedance amplifier TIA, and the regulating resistor R F under the operation of the SiPM chip is 910Ω, while the matching capacitor C F is 0.5pF. The bias terminal of the SiPM chip needs to be connected to a positive voltage. After passing through the transimpedance amplifier TIA, the signal output from the AOUT output terminal is a negative pulse. The transimpedance amplifier TIA is powered by dual power supplies, and the supply voltage is ±5V. By adjusting the regulating resistor R F and the matching capacitor C F to control the amplification factor of the output signal, increasing the resistor R F can increase the amplification factor, and the amplitude of the output signal increases. At the same time, it is necessary to adjust the appropriate value of the increased resistor R F for matching. Among them: the SiPM chip is TP3050, and the gain is 2.5*10 6, the spectral range is 250 - 950 nm, the wavelength of the mainstream single laser flow cytometry is 488, and the fluorescence range of the mainstream FITC staining is from 500 - 820 nm.
[0024] Combined with Figure 2 it can be known that the adjustable power supply unit includes rated resistors C68, C69, C70, C71, C53, C54, and C5 that are successively connected in parallel to pins 2, 6, 5, and 4 of the voltage regulator Z1. The 1 and 3 pins of the voltage regulator Z1 are connected to the input pins of the SiPM chip. Among them, the rated resistors C68, C69, C70, C71, C53, C54, and C5 filter successively to reduce resonance, and the voltage regulator Z1 adjusts the bias voltage output for the SiPM chip to break down.
[0025] Combined with Figure 3 it can be known that the AD conversion unit is connected to the Vout of the SiPM unit. It includes an AD chip and a U6AD module. The input end of the AD chip is data-connected to the output end of the U6AD module to collect the data output by the U6AD module, and then upload it after being collected by the FPGA. The AD conversion unit also includes an amplifier U5. A first circuit branch in which a rated resistor R24, a rated resistor R25, and a capacitor C10 are connected in parallel is connected in series between pins 3 and 4 of the amplifier U5. The 6 pin of the amplifier U5 is connected to the 6 pin of the U6AD module, and a rated resistor R27 is connected in series on the connection circuit between the two.
[0026] Furthermore, a capacitor C13 is connected in parallel between the 7 pin of the U6AD module and the connection between the rated resistor R27 and the 6 pin of the U6AD module.
[0027] Only some exemplary embodiments of the present invention are described above by way of illustration. Undoubtedly, for those of ordinary skill in the art, without departing from the spirit and scope of the present invention, the described embodiments can be modified in various different ways. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the protection scope of the claims of the present invention.
Claims
1. A fluorescence detector for a flow cytometer, characterized in that: It includes SiPM unit, adjustable power supply unit and filter AD conversion unit, among which: The SiPM unit includes a SiPM chip, a transimpedance amplifier TIA, and an adjustment resistor R F And matching capacitor C F The bias end of the SiPM chip is connected to the transimpedance amplifier TIA and the AOUT output end to output a negative pulse, and the regulating resistor R F And matching capacitor C F The two pins are connected in parallel to the input end and the output end of the transimpedance amplifier TIA; The adjustable power supply unit includes a rated resistor C68, a rated resistor C69, a rated resistor C70, a rated resistor C71, a rated resistor C53, a rated resistor C54 and a rated resistor C5 which are sequentially connected in parallel to pins 2, 6, 5 and 4 of the voltage regulator Z1, and pins 1 and 3 of the voltage regulator Z1 are connected to the input pins of the SiPM chip; The AD conversion unit is connected to the Vout of the SiPM unit, and includes an AD chip and a U6AD module. The input end of the AD chip is data-connected to the output end of the U6AD module.
2. The fluorescence detector for flow cytometer according to claim 1, characterized in that: The SiPM chip is TP3050, and the gain is 2.5*10 6 The spectral range is 250-950nm, the mainstream single laser flow band is 488, and the mainstream FITC staining fluorescence range is from 500-820nm.
3. The fluorescence detector for flow cytometer according to claim 1, characterized in that: The regulating resistor R located under the operation of the SiPM chip F is 910Ω, and the matching capacitor C F is 0.5pF.
4. The fluorescence detector for flow cytometer according to claim 1, characterized in that: The AD chip model is LTC2310CMSE-14, and its sampling rate is 2.2MSPS sampling rate and resolution is 14 bits.
5. The fluorescence detector for flow cytometer according to claim 1, characterized in that: The AD conversion unit further includes an amplifier U5, and pins 3 and 4 of the amplifier U5 are connected in series with a first circuit branch connected in parallel with a rated resistor R24, a rated resistor R25 and a capacitor C10; Pin 6 of the amplifier U5 is connected to pin 6 of the U6AD module, and a rated resistor R27 is connected in series in the circuit connecting the two.
6. The fluorescence detector for flow cytometer according to claim 5, characterized in that: A capacitor C13 is connected in parallel between the 7-pin connection of the U6AD module and the rated resistor R27 and the 6-pin connection of the U6AD module.