Fluorescence detection system and method

Abstract

Fluorescent light is emitted by a xenon lamp, is condensed by a concave mirror and then sequentially passes through a first reflecting mirror, a first grating and a beam splitter, one part of the fluorescent light enters a silicon photocell detector to detect whether a light source is stable or not, and the other part of the fluorescent light enters a detection groove and irradiates a sample in the groove and then is emitted out, passes through a second grating and then reaches a photomultiplier; and obtaining a fluorescence detection signal to detect a substance. By monitoring the stability of the light source on line in real time, unstable factors of the light source can be arranged in time, and the accuracy of fluorescence detection is ensured. The integrated detection groove can be conveniently positioned and replaced, and can be simultaneously suitable for a column detection groove or a capillary detection groove.

Description

Technical Field

[0001] The invention belongs to the field of fluorescence detection technology, and in particular relates to a fluorescence detection system and method. Background Art

[0002] The fluorescence detector mainly emits excitation light through the light source. After irradiating the fluorescent material, the fluorescence emitted by the fluorescent material is converted into monochromatic fluorescence through the monochromator and then irradiated onto the sample. The photomultiplier tube amplifies the received photocurrent and transmits it to the recorder to complete the detection. During use, the stability of the light source will directly affect the accuracy of the test results. However, the existing fluorescence detector does not have a measure to detect the stability of the light source online, and cannot timely detect the abnormality of the light source caused by insufficient power supply or problems with the xenon lamp itself. In addition, the detection slot is usually installed in the chassis and fixed on the bottom plate, so the replacement requires the whole machine to be disassembled, which is very inconvenient. In addition, the existing grating is only equipped with a zero position sensor. After each startup, the grating first turns to the zero position, and then starts to turn to the target position according to the setting to obtain the required wavelength. However, there is no means to detect whether the grating actually rotates accurately. Once there is command interference or communication problems, the effectiveness of fluorescence detection cannot be guaranteed. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a fluorescence detection system and method, which can monitor the stability of a light source online in real time.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: In one aspect, a fluorescence detection system comprises: Light sources, including xenon lamps, to produce fluorescent light; A focusing concave mirror, used to focus and reflect the fluorescent light; A first light entrance slit and a first reflector, wherein the fluorescent light reflected by the focusing concave mirror passes through the first light entrance slit and is then reflected by the first reflector; a first grating and a first light exit slit, wherein the first grating is used to re-reflect the fluorescence reflected by the first reflector according to a set wavelength and pass through the first light exit slit; The monitoring room includes a beam splitter and a silicon photocell detector. The beam splitter is used to reflect a part of the fluorescence passing through the first light emitting slit to the silicon photocell detector, and the silicon photocell detector is used to detect whether the light source is stable. A detection tank, another part of the fluorescence passes through the beam splitter to the detection tank and irradiates the sample to be tested in the tank before being emitted; The second light entrance slit and the second grating, the emitted fluorescence passes through the second light entrance slit and is emitted to the second grating, and is then reflected by the second grating according to the set wavelength; The second light emitting slit and the photomultiplier tube, the reflected fluorescence passes through the second light emitting slit to the photomultiplier tube to obtain a detection signal.

[0005] The light source also includes a light source box, in which a xenon lamp holder is arranged, the light source box has a top plate, the top plate has a window for installing the xenon lamp, and the top plate is provided with a pair of window baffles, each of the two baffles is provided with a semicircular hole, which is combined to form a clamping hole for fixing the upper end of the xenon lamp, and the baffle is also provided with a waist-shaped hole for adjusting the fixed position on the top plate.

[0006] The focusing concave mirror is arranged on a lens bracket located at one end of the light source box through an elastic support mechanism. The lens bracket is also provided with an adjustment component for adjusting the deflection of the focusing mirror. The adjustment component includes symmetrically arranged adjustment bolts and compression springs. The tail of the adjustment bolt passes through the lens bracket and abuts against the back of the focusing concave mirror, and the compression spring abuts between the lens bracket and the back of the focusing concave mirror.

[0007] The focusing concave mirror includes a mirror housing, a lens and a retaining ring. The front end of the mirror housing is open, and the outer edge has several bolt holes. The lens is adapted to the mirror housing. The front end mirror surface of the lens is a concave aspherical surface. The lens is arranged in the mirror housing through the opening. The retaining ring is arranged in front of the lens and is fixed to the mirror housing by passing bolts through the corresponding bolt holes.

[0008] The lens is made of aluminum alloy, and a protective film is coated on the front mirror surface.

[0009] The first and second gratings each include a grating body, a rotating base for mounting the grating body, a driving device for driving the rotating base to rotate, a first sensing rod rotating synchronously with the rotating base, and a zero position sensor for detecting the first sensing rod. They also include a target position sensor arranged on one side of the zero position sensor and used to detect the first sensing rod, a second sensing rod rotating together with the driving device, and a calibration sensor for detecting the second sensing rod. The driving device includes a driving motor connected to the bottom of the rotating base and a reducer connected to the bottom of the driving motor, and the second sensing rod is connected to the main shaft of the reducer.

[0010] The detection tank includes a flow cell rack, a flow cell arranged in the flow cell rack, and a flow cell clamping head fixed at both ends of the flow cell for fixing the flow cell. The flow cell rack has a light inlet for fluorescence to enter and illuminate the flow cell with the substance to be tested, and a light outlet for fluorescence to emit. The flow cell is a liquid column flow cell or a capillary flow cell.

[0011] The detection system also includes a detection light-shielding chamber, and a mounting window is provided on the side of the detection light-shielding chamber; the detection tank also includes a connecting spacer provided at one end of the flow pool rack, and a fixing plate is also provided at one end of the connecting spacer. The connecting spacer and the flow pool rack are installed into the detection light-shielding chamber through the mounting window, and are fixed to the outer wall of the detection light-shielding chamber at the mounting window through the fixing plate.

[0012] On the other hand, a detection method of a fluorescence detection system comprises the following steps: A. Use a xenon lamp to emit fluorescence to a focusing concave mirror; B. Concentrate and reflect the fluorescence through a concave mirror; C. The reflected fluorescence passes through the first light entrance slit and reaches the first reflector, and is reflected by the first reflector to the first grating, and reflects the spectrum band of the set wavelength through the first grating; D. The spectral band passes through the first light slit and then enters the monitoring room to the beam splitter. The beam splitter reflects part of the fluorescence to the silicon photocell detector, which detects whether the light source is stable. E. Another part of the light passes through the beam splitter and enters the detection tank, irradiating the sample in the tank and then emitting out; F. The emitted fluorescence passes through the second light entrance slit to the second grating, and is reflected by the second grating to produce a spectrum band of the set wavelength; G. The spectral band passes through the second light exit slit to the photomultiplier tube to obtain the detection signal.

[0013] In step C or F, the following grating control step is also included: H. The driving motor will drive the grating to rotate until the first sensing rod is detected by the zero position sensor and stops at the zero position; I. Then drive the grating to rotate towards the target position according to the instruction; J. When the first sensing rod is rotated to the point where the target position sensor detects a signal, the calibration sensor also obtains a signal from the second sensing rod, and the two signals match, the rotation stops, indicating that it is accurate and can reflect the set wavelength spectrum band.

[0014] A fluorescence detection system and method of the present invention is used. A xenon lamp emits fluorescence, which is focused by a concave mirror and then sequentially passes through a first reflector, a first grating, and a beam splitter. A portion of the fluorescence is detected by a silicon photocell detector to detect whether the light source is stable, and the other portion enters a detection tank, irradiates the sample in the tank, and then is emitted, passes through a second grating, and then reaches a photomultiplier tube to obtain a detection signal of the substance being tested. The accuracy of fluorescence detection can be guaranteed by online real-time detection of the stability of the light source. The integrated detection tank can be easily positioned and replaced, and can be applied to both column-mounted and capillary detection tanks. The focusing concave mirror can fine-tune the up and down, left and right deflection angles of the condenser through an elastic support mechanism and an adjustment component. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention is described in detail below with reference to the accompanying drawings and specific embodiments: Figure 1 A structural schematic diagram of a fluorescence detection system of the present invention from one viewing angle; Figure 2It is a structural schematic diagram of the fluorescence detection system of the present invention from another perspective; Figure 3 is a structural schematic diagram of a light source of the present invention; Figure 4 A three-dimensional diagram of a light-collecting concave mirror of the present invention installed in a light source box; Figure 5 For Figure 4 A three-dimensional diagram of the structure of the lens bracket hidden on the base Figure 6 It is a three-dimensional schematic diagram of a light-collecting concave mirror of the present invention; Figure 7 A cross-sectional view of the light-collecting concave mirror installation structure of the present invention; Figure 8 is an enlarged schematic diagram of the elastic support mechanism of the present invention; Fig. 9 It is a schematic diagram of the installation of the grating of the present invention; Fig.10 is a schematic structural diagram of the grating of the present invention; Fig.11 It is a schematic diagram of the installation of the zero position sensor and the target position sensor of the present invention; Fig.12 It is a schematic diagram of the installation position of the monitoring room of the present invention; Fig.13 This is a schematic diagram of the structure of the monitoring room of the present invention; Fig.14 It is a structural schematic diagram of the monitoring room and the detection tank from one perspective of the present invention; Fig.15 It is a schematic diagram of the structure inside the monitoring room of the present invention; Fig.16 It is a structural schematic diagram of the monitoring room and the detection slot of the present invention from another perspective; Fig.17 It is a structural schematic diagram of the detection slot installation structure of the present invention; Fig.18 It is a structural schematic diagram of the fixing plate of the present invention; Fig.19 It is a structural schematic diagram of the installation window of the present invention; Fig. 20 It is a schematic structural diagram of the connection spacer and the flow cell assembly of the present invention; Fig.21 It is a schematic structural diagram of the flow cell assembly of the present invention; Fig. 22 It is a schematic structural diagram of the light inlet and outlet holes of the flow cell rack of the present invention; Fig.23 It is a schematic structural diagram of the liquid phase column flow cell of the present invention; Fig.24It is a schematic diagram of the connection between the flow cell compression head and the inlet and outlet pipes of the present invention; Fig.25 It is a schematic diagram of the capillary detection slot installation structure of the present invention; Fig.26 It is a schematic structural diagram of a capillary flow cell of the present invention; Fig. 27 It is a structural schematic diagram of the outlet baffle of the present invention; Fig.28 It is a structural schematic diagram of the connection spacer of the present invention; Fig.29 It is a schematic structural diagram of the second grating and the second light-emitting slit of the present invention; Fig.30 This is the optical principle of the present invention. DETAILED DESCRIPTION

[0016] A fluorescence detection system of the present invention is as follows Figure 1-Figure 2 As shown, it mainly includes a light source 1, a focusing concave mirror 2, a first light inlet slit 3, a first reflector 4, a first grating 5, a first light outlet slit 6, a monitoring chamber 8, a detection slot 9, a second light inlet slit 10, a second grating 11, and a second light outlet slit 12 (see Fig.23 ) and a photomultiplier tube 13. Among them, like Figure 3 As shown, the light source 1 includes a xenon lamp 14 for emitting fluorescence. The light source 1 also includes a light source box. The light source box mainly includes a bottom plate 101, a top plate 105, and two side plates 102 ( Figure 1 , 2 The left side panel is hidden, and only the right side panel is shown) and the front panel 103, etc., form a box-like structure. A xenon lamp holder 106 is provided on the bottom panel 101 in the box. A circular window 109 for the xenon lamp 14 to be installed is provided on the top panel 105. The xenon lamp 14 can be inserted through the window 109, and the bottom is installed on the xenon lamp holder 106 through threads, while the upper end of the xenon lamp 14 is exposed from the window 109. A pair of circular window baffles 107 are also provided on the top panel 105. A semicircular hole is provided on each of the two baffles 107, and a clamping hole for fixing the upper end of the xenon lamp 14 is formed by merging. The baffles 107 are also provided with a waist-shaped hole 108 for adjusting the position on the top panel 105, which can be adjusted accordingly on the top panel according to different specifications of xenon lamps 14 to meet the installation and positioning of xenon lamps 14 of different models and sizes.

[0017] Therefore, when in use, loosen the bolts on the waist-shaped hole 108 (not shown in the figure), move the circular window baffles 107 to both sides to expose the window 109, select the xenon lamp 14 of the required specifications, insert it into the light source box through the window and install it on the xenon lamp holder 106, and then move the two circular window baffles 107 relative to each other so that the clamping hole just clamps and positions the exposed end of the xenon lamp 14, which plays the role of shading the window and fixing the xenon lamp 14, and then tighten the bolts on the waist-shaped hole 108 to fix it to the top plate 105.

[0018] In addition, a circular light-emitting hole 110 is provided on the front panel 103, and a conical light-shielding tube 111 is also provided at the front end of the front panel 103. The diameter of the end of the light-shielding tube 111 is the same as that of the circular light-emitting hole 110 of the front panel 103 and they are connected to each other, and the diameter gradually decreases from back to front. The light emitted by the xenon lamp 14 is reflected by the focusing concave mirror 2 at the rear of the light source box 13, and then emitted from the circular light-emitting hole 110 to the light source box, and passes through the light-shielding tube 1111 to enter the subsequent detection structure of the fluorescence detector 1.

[0019] like Figure 4-Figure 8 As shown, the focusing concave mirror 2 is arranged at the rear of the light source box 1, and is used to focus and reflect the fluorescence emitted by the xenon lamp. It includes a lens 21. The lens 21 can be made of aluminum alloy material, and is preferably made of super-hard aluminum alloy, etc., and its front end mirror surface is a concave aspheric surface, and the surface is coated with a protective film. The lens 21 made of this material can be cut and polished by a CNC machine tool, which is convenient to process, can reduce the processes such as aluminum plating mold, and the material cost is only about one-tenth of the traditional quartz material double-layer film coating, and has stable performance and long service life.

[0020] A mirror body bracket 22 is provided on the back side of the focusing concave mirror 2. The focusing concave mirror 2 also includes a cylindrical mirror housing 23 and a clamping ring 24. The front end of the mirror housing 23 is open, and the outer edge has several axial bolt holes 25 protruding. The lens 21 is adapted to the mirror housing 23. The lens 21 is arranged in the mirror housing 23 through the opening. The clamping ring 24 is arranged in front of the lens 21 and the edge of the focusing surface of the lens 21 is fixed to the mirror housing 23 through bolts 26 inserted into the corresponding bolt holes 25. The focusing concave mirror 2 is arranged on the mirror body bracket 22 as a whole through an elastic support mechanism. The rear middle of the mirror housing 23 also has a cavity 27 protruding backwards, and an elastic support mechanism is arranged in the cavity 27, specifically including a support spring 281 and a support bolt 282, and an axial step hole 283 is opened in the center of the cavity 27, and an annular groove 284 for limiting the support spring 281 is also provided outside the step hole 283, one end of the support spring 281 is against the lens 21, and the other end is arranged in the annular groove 284 and against the rear wall of the cavity 27, and a rocking ring 285 with a tapered inner hole is arranged in the step hole 283, one end of the support bolt 282 is a ball head arranged in the cavity 27 and matched with the tapered inner hole of the rocking ring 285, and the other end passes through the rocking ring 285, the rear wall of the cavity 27, and the mirror body bracket 22 in sequence, and is fastened to the mirror body bracket 22 through a nut 286. The elastic support mechanism can realize the support positioning of the lens 21, and can also meet the floating setting required for the deflection adjustment of the mirror housing 23.

[0021] The mirror body bracket 22 is also provided with two groups of adjustment components for adjusting the deflection of the focusing concave mirror 2. Each group of adjustment components includes symmetrically arranged adjustment bolts 291 and compression springs 292, that is, one group is provided on the left and right sides of the support bolt 282, and one group is provided on the upper and lower sides. The tail of the adjustment bolt 291 passes through the mirror body bracket 22 and abuts against the back of the mirror housing 23 of the focusing concave mirror 2, and the compression spring 292 abuts between the mirror body bracket 22 and the back of the focusing concave mirror 2. In addition, the rear end surface of the mirror housing 23 is also provided with two guide posts 293 that are integrated with the mirror housing 23 and correspond to the compression springs 292, and the compression springs 292 are respectively sleeved on the corresponding guide posts 293.

[0022] In this way, when the deflection angle of the focusing concave mirror 2 needs to be adjusted, taking the left and right angle adjustment as an example, the focusing concave mirror 2 can be driven to deflect to the right as a whole by pushing the mirror housing 23 forward through the left adjusting bolt 291, and by moving the adjusting bolt 291 backward, the compression spring 292 on the right side deflects to the left, so that the fluorescence reflected by the focusing concave mirror 2 can pass through the slit. The same is true for the up and down angle adjustment.

[0023] The first light entrance slit 3 is arranged in front of the conical light shielding tube 111. The first reflector 4 is arranged in front of the first light entrance slit 3. The fluorescent light reflected by the focusing concave mirror 2 passes forward through the conical light shielding tube 111, the first light entrance slit 3 to the first reflector 4 in sequence, and is reflected by the first reflector 4 to the first grating 5.

[0024] like Figure 9-11 As shown, the first grating 5 is arranged at the diagonally opposite side of the first reflector 4, and is used to reflect the fluorescence reflected by the first reflector 4 into a spectrum band of a set wavelength. The first grating 5 includes a grating body 51, a rotating base 52 for mounting the grating body 51, a driving device for driving the rotating base 52 to rotate, a first sensing rod 54 that rotates synchronously with the rotating base 52, and a zero position sensor 55 for detecting the first sensing rod 54. The grating body 51 is mounted on the rotating base 52, and the driving device includes a driving motor 56 connected to the bottom of the rotating base 52 and a reducer 57 connected to the bottom of the driving motor 56. The rotating base 52 is driven to rotate by the driving motor 56, so that the grating body 51 and the first sensing rod 54 rotate at a corresponding angle. The grating also includes a target position sensor 58 disposed on one side of the zero position sensor 55 and used to detect the first sensing rod 54, a second sensing rod 59 horizontally connected to the main shaft of the reducer 57 and capable of rotating together with the main shaft 50 of the reducer 57, and a calibration sensor 53 disposed on the outside of the reducer 57 and used to detect the second sensing rod 59. The zero position sensor 55, the target position sensor 58, and the calibration sensor 53 can all be photoelectric switches.

[0025] The working principle of the grating is as follows: after each start-up, the drive motor 56 will drive the grating to rotate until the first sensing rod 54 is detected by the zero position sensor 55, stop at the zero position, and then rotate to the target position according to the instruction. When the first sensing rod 54 is detected by the target position sensor 58, the calibration sensor 53 should also obtain the signal of the second sensing rod 59, and the two signals can match (the first sensing rod 54 and the second sensing rod 59 have a corresponding speed ratio), which indicates that the grating has rotated to the right position and can accurately reflect the spectral band of the set wavelength.

[0026] Since the target position sensor 58 and the calibration sensor 53 are provided, the first and second sensing rods 54 and 59 can be detected respectively, and verified based on the two detection data, so that the grating can be calibrated to see whether it is rotated in place according to the instructions each time it is used, so as to ensure that the spectral band of accurate wavelength can be obtained each time.

[0027] like Figure 12-16As shown, the first light emitting slit 6 is arranged on the back side of the first reflector 4. The monitoring room 8 is arranged on the rear side of the first light emitting slit 6. The monitoring room 8 is surrounded by a light shielding plate 7 to form a light shielding room, and a light entrance window 71 and a light exit window 72 are respectively opened on the front and rear sides thereof. The monitoring room 8 has a beam splitter 81, a first convex mirror sleeve 82 and a silicon photocell detector 83. The beam splitter 81 is arranged at a certain deflection angle, which can pass part of the fluorescence emitted by the light source 1 for subsequent material detection, and reflect part to the first convex mirror sleeve 82. The first convex mirror sleeve 82 is arranged on the side of the beam splitter 81, receives the emitted fluorescence of the beam splitter 81 and focuses the light; the silicon photocell detector 83 is arranged on the rear side of the first convex mirror sleeve 82, receives the focused light of the first convex mirror sleeve 82 to detect whether the energy intensity of the light source 11 is stable. The beam splitter 81 can be specifically designed to include a lens base 811, a light-transmitting window 812 provided on the lens base 811, and a reflector 813 for shielding a portion of the light-transmitting window 812. The reflector 813 usually shields the lower third of the light-transmitting window 812.

[0028] When the fluorescence emitted by the light source 1 obtains the spectral band of the set wavelength through the first grating 5, it passes through the first light exit slit 6 and then through the light entrance window 71 to enter the monitoring room 8, and is directly emitted to the beam splitter 81. Two-thirds of the fluorescence passes through the beam splitter 81 through the light passing window 82 and then through the light exit window 72 to the subsequent detection slot 9 for fluorescent substance detection; and one-third of the fluorescence is reflected by the reflection plate of the beam splitter 81 to the first convex mirror sleeve 82 and then emitted to the silicon photocell detector 83. The energy intensity of the light source 1 is detected in real time by the silicon photocell detector 83, thereby realizing online detection of the stability of the light source 1.

[0029] like Figure 17-Figure 28 As shown, a detection chamber 91 is provided at the rear side of the light exit window 72. The detection chamber 91 is a light shielding chamber (including the surrounding and the top) composed of a plurality of light shielding plates. The detection chamber 91 has a light entrance circular hole 914, a light exit circular hole 915 and an installation window 96 arranged in different directions. A second convex mirror sleeve 92 is provided between the light exit window 72 and the light entrance circular hole 914. The light entrance circular hole 914 and the light exit circular hole 915 are arranged at 90 degrees to each other (see Fig.14 ), the mounting window 96 is arranged at the opposite position of the light incident circular hole 914.

[0030] The detection chamber 91 is provided with a detection tank body, including a fixed plate 94, a connecting spacer 95, and a flow cell assembly for the substance to be detected, which are connected in sequence. The fixed plate 94 is larger than the installation window 96 and is arranged on the outer wall of the light shielding plate 5 at the installation window 96. The cross section of the connecting spacer 95 and the flow cell assembly is smaller than the installation window 96, and can extend into the detection chamber 91 through the installation window 96. Figure 3-Figure 4As shown, the specific installation method of the fixing plate 94 can be achieved by providing a screw hole 911 for connecting with the fixing plate 94 and a positioning column 913 matching with the positioning hole 912 on the fixing plate 94 on the shading plate with the installation window 96. The screw hole 911 is arranged on the upper and lower sides of the installation window 96, and the positioning column 913 is arranged on the left and right sides of the installation window 96. The fixing plate 94 is first positioned by the positioning column 913, and then fixed to the shading plate by passing the bolt through the screw hole 911.

[0031] The flow cell assembly mainly includes a flow cell frame 991, a flow cell arranged in the flow cell frame 991, and a flow cell clamping head 992 fixed at both ends of the flow cell to fix the flow cell. The flow cell frame 991 can be made of plastic material, while the flow cell clamping head 992 is made of metal material and is inserted from the upper and lower ends of the flow cell frame 991. The flow cell frame 991 has a light inlet hole 916 and a light outlet hole 917 which are respectively connected to the light inlet hole 914 and the light outlet hole 915, that is, the light inlet hole 916 and the light outlet hole 917 are also arranged at 90 degrees to each other. A second convex mirror sleeve 93 is also arranged between the light outlet hole 917 and the light outlet hole 915. The flow cell assembly also includes a flow cell inlet baffle 918 and a flow cell pressure plate 919 which are respectively arranged on both sides of the flow cell frame 991. The flow cell inlet baffle 918 is provided with a light-transmitting window 920 which communicates with the second convex mirror sleeve 92 and the light inlet hole 916, and the flow cell pressure plate 919 is provided with a flow cell observation hole 921.

[0032] When the liquid phase column detection tank is selected, the flow cell is a liquid phase column flow cell, including a square quartz glass tube 922 arranged between two flow cell clamping heads 992, a flow cell inlet pipe 923 passing from the bottom into the flow cell clamping head 992 at the lower end, and a flow cell outlet pipe 924 passing from the upper part into the flow cell clamping head 992 at the upper end, and a gasket 925 is also arranged between the flow cell clamping heads 992 at the upper and lower ends and the square quartz glass tube 922, and the flow cell clamping heads 992 and the gasket 925 are both provided with flow holes 926 connected to the square quartz glass tube 922, and the flow cell inlet and outlet pipes 923, 924 are metal hard pipes and are respectively fixed to the corresponding flow cell clamping heads 992. The other ends of the flow cell inlet and outlet pipes 923, 924 can pass through the slots 928 opened on the connecting spacer 95, and pass through the fixing plate 94 through the installation window 96.

[0033] When a capillary detection tank is used, compared with a liquid phase column detection tank, the only difference is that the flow pool is a capillary 927, and pipe joints 929 are respectively provided on the flow pool clamping heads 992 at the upper and lower ends, and an observation window member 930 having an observation window and communicating with the light inlet 916 and the light outlet 917 is provided between the two flow pool clamping heads 992. A capillary 927 passes through the two pipe joints 929, the two flow pool clamping heads 992, and the observation window member 930 after being sleeved with a protective sleeve 935 such as a PEEK material, and the irradiated section of the capillary 927 located in the observation window member 930 is transparent and is not sleeved with the protective sleeve 935, and is used for fluorescent irradiation of the object to be measured in the tube. The irradiated section can be made by sintering the capillary 927. By providing the protective sleeve 935, the pipe joint 929 can tighten and fix the capillary 927 sleeved with the protective sleeve 935. The two ends of the flexible capillary 927 can also pass through the slots 928 of the connecting spacer 95 and the mounting window 96 to pass through the fixing plate 94. The observation window is connected to the flow cell observation hole 921 on the flow cell pressing plate 919.

[0034] An outlet baffle 931 is connected to one side of the flow cell rack 991 having a light outlet hole 917 . The outlet baffle 931 is a U-shaped structure and is connected to the flow cell rack 991 by bolts passing through screw holes 932 , so as to shield both sides of the fluorescence coming out of the light outlet hole 917 .

[0035] One end surface of the connecting spacer 95 also has a screw hole 932 connected to the fixing plate 94, and the side surface has a weight-reducing through hole 934. The slot 928 is opened on one side surface of the connecting spacer 95 and is pressed and fixed by a pressing plate 933.

[0036] Since the entire detection tank body is an integrated structure, when the detection tank needs to be installed or replaced, the replacement can be completed by simply disassembling and assembling the installation window 96 and the fixing plate 94. At the same time, the liquid column and the capillary 927 detection tank adopt the same size and structure, and no debugging is required during replacement. The position matching between the second convex mirror sleeve 92, the light entrance hole 914, the flow cell, the second convex mirror sleeve 93, and the light exit hole 915 can be ensured, which is not only simple and convenient, but also expands the range of detected substances.

[0037] like Fig.29 As shown, the fluorescence emitted from the light-emitting circular hole 915 passes through the second light-inlet slit 10 and then is emitted to the second grating 11. The structure and working principle of the second grating 11 are the same as those of the first grating 5. It can reflect the fluorescence out of a spectral band of a set wavelength, and then pass through the second light-emitting slit 12 and then be emitted to the photomultiplier tube 13 to obtain the detection signal of the substance being measured.

[0038] Combination Fig.30 As shown, the detection method of the fluorescence detection system of the present invention comprises the following steps: A. The xenon lamp 14 emits fluorescent light to the focusing concave mirror 2; B. Concentrate and reflect the fluorescence through the concave mirror 2; C. The reflected fluorescence passes through the first light entrance slit 3 and reaches the first reflector 4, and is reflected by the first reflector 4 to the first grating 5, and reflects the spectrum band of the set wavelength through the first grating 5; D. After passing through the first light exit slit 6, the spectral band enters the monitoring chamber 8 and reaches the beam splitter 81. The beam splitter 81 reflects a part of the fluorescence to the silicon photocell detector 83, and the silicon photocell detector 83 is used to detect whether the light source is stable; E. Another part of the light passes through the beam splitter 81 and enters the detection slot 9, irradiating the sample in the slot and then exits; F. The emitted fluorescence passes through the second light entrance slit 10 to the second grating 11, and is reflected by the second grating 11 to produce a spectrum band of a set wavelength; G. The spectral band passes through the second light exit slit 12 to the photomultiplier tube 13 to obtain a detection signal.

[0039] In step C or F, the following grating control step is also included: H. The driving motor 56 drives the grating to rotate until the first sensing rod 54 is detected by the zero position sensor 55 and stops at the zero position; I. Then drive the grating to rotate towards the target position according to the instruction; J. When the first sensing rod 54 is rotated to the point where the target position sensor 58 detects a signal, the calibration sensor 53 also receives a signal from the second sensing rod 59, and the two signals match, the rotation stops, indicating that the target position sensor 58 is accurately positioned and can reflect the set wavelength spectrum band.

[0040] However, those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A fluorescence detection system, characterized in that: include: Light sources, including xenon lamps, to produce fluorescent light; A focusing concave mirror, used to focus and reflect the fluorescent light; A first light entrance slit and a first reflector, wherein the fluorescent light reflected by the focusing concave mirror passes through the first light entrance slit and is then reflected by the first reflector; a first grating and a first light exit slit, wherein the first grating is used to re-reflect the fluorescence reflected by the first reflector according to a set wavelength and pass through the first light exit slit; The monitoring room includes a beam splitter and a silicon photocell detector. The beam splitter is used to reflect a part of the fluorescence passing through the first light emitting slit to the silicon photocell detector, and the silicon photocell detector is used to detect whether the light source is stable. A detection tank, another part of the fluorescence passes through the beam splitter to the detection tank and irradiates the sample to be tested in the tank before being emitted; The second light entrance slit and the second grating, the emitted fluorescence passes through the second light entrance slit and is emitted to the second grating, and is then reflected by the second grating according to the set wavelength; The second light emitting slit and the photomultiplier tube, the reflected fluorescence passes through the second light emitting slit to the photomultiplier tube to obtain a detection signal.

2. The fluorescence detection system according to claim 1, characterized in that: The light source also includes a light source box, in which a xenon lamp holder is arranged, the light source box has a top plate, the top plate has a window for installing the xenon lamp, and the top plate is provided with a pair of window baffles, each of the two baffles is provided with a semicircular hole, which is combined to form a clamping hole for fixing the upper end of the xenon lamp, and the baffle is also provided with a waist-shaped hole for adjusting the fixed position on the top plate.

3. The fluorescence detection system according to claim 2, characterized in that: The focusing concave mirror is arranged on a lens bracket located at one end of the light source box through an elastic support mechanism. The lens bracket is also provided with an adjustment component for adjusting the deflection of the focusing mirror. The adjustment component includes symmetrically arranged adjustment bolts and compression springs. The tail of the adjustment bolt passes through the lens bracket and abuts against the back of the focusing concave mirror, and the compression spring abuts between the lens bracket and the back of the focusing concave mirror.

4. The fluorescence detection system according to claim 3, characterized in that: The focusing concave mirror includes a mirror housing, a lens and a retaining ring. The front end of the mirror housing is open, and the outer edge has several bolt holes. The lens is adapted to the mirror housing. The front end mirror surface of the lens is a concave aspherical surface. The lens is arranged in the mirror housing through the opening. The retaining ring is arranged in front of the lens and is fixed to the mirror housing by passing bolts through the corresponding bolt holes.

5. The fluorescence detection system according to claim 4, characterized in that: The lens is made of aluminum alloy, and a protective film is coated on the front mirror surface.

6. The fluorescence detection system according to claim 1, characterized in that: The first and second gratings each include a grating body, a rotating base for mounting the grating body, a driving device for driving the rotating base to rotate, a first sensing rod rotating synchronously with the rotating base, and a zero position sensor for detecting the first sensing rod. They also include a target position sensor arranged on one side of the zero position sensor and used to detect the first sensing rod, a second sensing rod rotating together with the driving device, and a calibration sensor for detecting the second sensing rod. The driving device includes a driving motor connected to the bottom of the rotating base and a reducer connected to the bottom of the driving motor, and the second sensing rod is connected to the main shaft of the reducer.

7. The fluorescence detection system according to claim 1, characterized in that: The detection tank includes a flow cell rack, a flow cell arranged in the flow cell rack, and a flow cell clamping head fixed at both ends of the flow cell for fixing the flow cell. The flow cell rack has a light inlet for fluorescence to enter and illuminate the flow cell with the substance to be tested, and a light outlet for fluorescence to emit. The flow cell is a liquid column flow cell or a capillary flow cell.

8. The fluorescence detection system according to claim 7, characterized in that: The detection system also includes a detection light-shielding chamber, and a mounting window is provided on the side of the detection light-shielding chamber; the detection tank also includes a connecting spacer provided at one end of the flow pool rack, and a fixing plate is also provided at one end of the connecting spacer. The connecting spacer and the flow pool rack are installed into the detection light-shielding chamber through the mounting window, and are fixed to the outer wall of the detection light-shielding chamber at the mounting window through the fixing plate.

9. The detection method of the fluorescence detection system according to claim 1, characterized in that: The following steps are involved: A. Use a xenon lamp to emit fluorescence to a focusing concave mirror; B. Concentrate and reflect the fluorescence through a concave mirror; C. The reflected fluorescence passes through the first light entrance slit and reaches the first reflector, and is reflected by the first reflector to the first grating, and reflects the spectrum band of the set wavelength through the first grating; D. The spectral band passes through the first light slit and then enters the monitoring room to the beam splitter. The beam splitter reflects part of the fluorescence to the silicon photocell detector, which detects whether the light source is stable. E. Another part of the light passes through the beam splitter and enters the detection tank, irradiating the sample in the tank and then emitting out; F. The emitted fluorescence passes through the second light entrance slit to the second grating, and is reflected by the second grating to produce a spectrum band of the set wavelength; G. The spectral band passes through the second light exit slit to the photomultiplier tube to obtain the detection signal.

10. The detection method of the fluorescence detection system according to claim 9, characterized in that: In step C or F, the following grating control step is also included: H. The driving motor will drive the grating to rotate until the first sensing rod is detected by the zero position sensor and stops at the zero position; I. Then drive the grating to rotate towards the target position according to the instruction; J. When the first sensing rod is rotated to the point where the target position sensor detects a signal, the calibration sensor also obtains a signal from the second sensing rod, and the two signals match, the rotation stops, indicating that it is accurate and can reflect the set wavelength spectrum band.

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