Separation and detection method and device for miniature integrated fluorescent gas chromatography

Abstract

The invention discloses a separation and detection method and device for miniature integrated fluorescent gas chromatography, and belongs to the technical field of gas chromatography. According to the method, an enrichment module, a sample introduction module, a separation module and a detection module are creatively integrated by combining an MEMS micromachining technology with a fluorescent sensing technology; the miniaturization, portability and intellectualization of the gas chromatograph are realized; according to the device, an analyte is pre-concentrated through the enrichment module, so that the sensitivity of sample detection is improved; the separation module is used for efficiently separating complex analytes; the fluorescence sensor is used as a detection module, nondestructive qualitative and quantitative detection of analytes is realized, and the whole device has the advantages of small size, low power consumption, fast response, high sensitivity, high integration level and the like, and is suitable for distinguishing and identifying, fast and reversible in-situ real-time detection of micro-trace gas in the fields of environmental monitoring, industrial production, express logistics and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of gas chromatographs, and in particular relates to a separation and detection method and device for a micro-integrated fluorescence gas chromatography. Background Art

[0002] Miniaturization of chromatographs is necessary to achieve rapid trace analysis, but it is also the bottleneck limiting in-situ real-time detection.

[0003] According to the survey, the patent applications named "A gas chromatography device" (CN220795137U), "Portable gas chromatograph and portable gas chromatography system" (CN211374643U), "Micro gas chromatography system" (US-20200049673-A1) and "Chip-scale gas chromatography system" (CN211374643U) are the most popular. The existing technologies such as the patent application for "chromatography" (US-2018164260-A1) all adopt the design method of simple combination of three modules of "concentrator + chromatographic column + detector", which is a non-improved and reduced version of the traditional desktop gas chromatograph and has not truly realized the integrated design. This design method results in the detection sensitivity of the chromatograph only reaching the ppm level, and it is impossible to accurately detect extremely low concentration analytes. Moreover, this design method will aggravate the problems of interface breakage and leakage and corrosion and aging of sensitive surfaces, resulting in an increase in the economic cost of the instrument and an increase in the difficulty of maintenance. The detectors used in these technologies, such as micro thermal conductivity detector (μTCD), micro flame ionization detector (μFID) and micro photoionization detector (μPID), require high-temperature heating devices or high-power ultraviolet light sources, resulting in complex device structures and high energy consumption. These detectors often use high-purity gases (>99.9%) such as hydrogen, nitrogen, argon, etc. as fuel gas and carrier gas, which will damage the sample and make it impossible to use it in conjunction with other test instruments.

[0004] In summary, the existing chromatograph miniaturization technology has problems such as incompatible module splicing, complex and bulky detectors and accessories, and low overall integration of the device. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a separation and detection method and device for a miniature integrated fluorescence gas chromatography, which applies the principle of fluorescent chemical sensing to achieve non-destructive, pure gas-free, and low detection limit detection; the one-piece molding method avoids leakage and breakage problems caused by incompatible interface materials, and the overall device has the advantages of high sensitivity, small size, light weight, low energy consumption, and integrated integration.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A separation and detection method for a micro-integrated fluorescence gas chromatography comprises the following steps: introducing an analyte into an enrichment module and concentrating the analyte, the concentrated analyte flows into a separation module through an automated sampling module, is carried by a carrier gas and interacts with a stationary phase to achieve separation; the separated components are loaded into a detection module, diffuse-interact-desorb in an excited fluorescence sensitive unit, and then the radiation path of the fluorescence sensitive unit is changed; the detection module converts a dynamically changing fluorescence signal into an electrical signal, generates a chromatogram after analyzing the electrical signal, and outputs the concentration and type of each component.

[0008] The separation module comprises a primary separation column or a multi-stage separation column in which a plurality of different secondary separation columns are connected in series.

[0009] The fluorescent sensing unit is designable and is customized and synthesized according to the characteristics of the analyte. It is a combination of one or more organic fluorescent small molecules, fluorescent high molecular polymers and metal organic fluorescent complexes. The sensing mechanism of the fluorescent sensing unit is a combination of one or more of the energy transfer, specific binding / reaction and microenvironment disturbance mechanisms between the fluorescent sensing unit and the analyte. According to the relative positions of the excitation light source, the fluorescent sensing unit and the photosensitive component, the detection mode is transmission type, reflection type and diffuse reflection type.

[0010] A separation and detection device for a miniature integrated fluorescence gas chromatography comprises a shell 1, wherein an enrichment module 4, an injection module 5, a separation module 6 and a detection module 7 are arranged inside the shell 1; an analyte injection port and a carrier gas injection port are arranged at the upper end of the shell 1; the analyte injection port is connected to the inlet of the enrichment module 4, the carrier gas injection port is connected to the first inlet of the injection module 5, the outlet of the enrichment module 4 is connected to the second inlet of the injection module 5, the outlet of the injection module 5 is connected to the inlet of the separation module 6, and the outlet of the separation module 6 is connected to the inlet of the detection module 7.

[0011] The signal output of the detection module 7 is connected to the signal input of the data processing system 10 .

[0012] The outlet of the detection module 7 is connected to the inlet of the exhaust gas processor 9.

[0013] The separation module 6 and the detection module 7 are optionally equipped with a temperature control system 8 , and the temperature control system 8 is used to control the column temperature of the separation module 6 and the desorption temperature of the detection module 7 .

[0014] The first inlet of the injection module 5 is the first air inlet 13, and the first air inlet 13 is connected to the carrier gas 3 via the first flowmeter 11; the second inlet of the injection module 5 is the second air inlet 14, and the second air inlet 14 is connected to the outlet of the enrichment module 4 via the second flowmeter 18; the outlet of the injection module 5 is the air outlet 15, the inlet of the separation module 6 is the separation system inlet end 16, the outlet of the separation module 6 is the separation system outlet end 17, and the air outlet 15 is connected to the separation system inlet end 16; the injection module 5 adjusts the split ratio of the first flowmeter 11 and the second flowmeter 18 according to different test requirements, and has the characteristics of low power consumption and miniaturization, with power consumption less than 1600mW and a volume less than 8cm 3 .

[0015] The separation module 6 utilizes MEMS technology to etch a connected parallel groove channel 19 with a microstructure array 20 on a substrate 22, and a separation system inlet end 16 and a separation system outlet end 17 connected to both ends of the channel; the parallel groove channel 19 adopts a square spiral, circular spiral or serpentine layout; the microstructure of the microstructure array 20 is one of a microcone, a microsquare column, a microcylinder or a microelliptical column; the inlet of the separation module 6 and the injection module 5 are arranged at one end of the parallel groove channel 19, the outlet of the separation module 6 and the detection module 7 are arranged at the other end of the parallel groove channel 19, and the parallel groove channel 19 and the cover plate 21 are packaged using a silicon-silicon bonding process.

[0016] The surface of the separation module 6 is coated with a separation material. The separation material uses a dual stationary phase structure of superimposed polar and non-polar materials. After dynamic coating and curing processes, the separation material is uniformly modified on the surface of the parallel groove channels 19 and the microstructure array 20.

[0017] The housing 1 is made of high-strength polymer or carbon fiber antistatic material that is breathable, water-tight, lightweight, impact-resistant and vibration-proof.

[0018] The housing 1 has two structures: a handle type and a table-based type.

[0019] The enrichment module 4 includes multiple layers of adsorption materials, each layer of adsorption materials has different adsorption characteristics; the enrichment module 4 includes an automatic desorption device to release the adsorbed components after the sample is concentrated.

[0020] The adsorption material filled in the enrichment module 4 is one or more combinations of carbon nanotubes, porous silica, MOFs, high molecular foam polymers and metal oxides.

[0021] The detection module 7 is embedded in the exit of the separation module 6. The detection module 7 is a sensor based on the principle of converting fluorescent chemical signals into electrical signals, including an excitation light source 24, a fluorescent sensitive unit 26 and a photosensitive component 25. The relative positions of the components are adjusted according to the exit of the separation module 6.

[0022] The excitation light source 24 is an LED lamp bead with a power consumption of 10 to 60 μW and a central wavelength that is the optimal excitation light band of the fluorescence sensitive unit 26; a bandpass filter 27 is arranged on one side of the excitation light source 24, and its light transmission range is determined according to the Stokes shift of the fluorescence sensitive unit 26; the fluorescence sensitive unit 26 adopts an organic fluorescent material, which is deposited in the parallel groove channel 19 at the outlet of the separation module 6, thereby realizing the integration of separation and detection; the photosensitive component 25 adopts a PIN-type photodiode, a phototransistor or a photomultiplier tube, which receives the light signal and amplifies and converts it into an electrical signal; a filter 28 is arranged at the front end of the photosensitive component 25.

[0023] By controlling the divergence angle and the spot area of ​​the excitation light source 24, the light intensity signal-to-noise ratio and the excitation efficiency are improved.

[0024] The adsorption material used by the exhaust gas processor 9 is one or more combinations of activated carbon, polypropylene, polycarbonate or polyimide resin.

[0025] The data processing system 10 includes an analysis unit, a communication unit and a display unit. The analysis unit processes the time-domain electrical signal into a digital signal of the concentration and type of each component of the analyte, and the digital signal is sent to the display unit via the communication unit. The communication mode of the communication unit includes at least one of the following: wired, Bluetooth, NFC, WIFI and mobile data; the display unit is a touch screen panel, or a screen panel equipped with an additional input unit.

[0026] The separation and detection device of the miniature integrated fluorescence gas chromatography comprises a power supply 12, which comprises a battery management circuit and a charging circuit. The battery management circuit is responsible for the charging, discharging and protection functions of the battery, and the charging circuit supports the USB charging function.

[0027] The micro-integrated fluorescence gas chromatography separation and detection device is formed by 3D micro-machining, each module is arranged in a vertical stack or parallel arrangement structure, and the overall size of the device is less than 400cm 3 , is portable and suitable for field detection and mobile monitoring tasks, and achieves long-term operation powered by secondary batteries through low-power design.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The method of the present invention uses a detection module developed based on the principle of fluorescent chemical sensing, which only requires an excitation light source, a filter, a fluorescent sensing unit and simple photosensitivity components to achieve non-destructive and rapid detection at the ppt level, without the need for a high-temperature heat source and necessary pure gas; at the same time, analytes can be distinguished and identified based on the cross-complementary information of time-resolved response kinetics and retention time, thereby achieving accurate qualitative analysis; the fluorescent sensing unit has strong designability, and the core building blocks can be changed according to specific needs, thereby achieving both selective detection and universal detection.

[0030] The device of the present invention is integrated, which can reduce the volume of the chromatographic device, reduce the overall weight of the device, and is easy to carry. It can realize in-situ real-time detection in complex indoor / outdoor environments, avoid problems such as interface breakage and gas leakage caused by incompatibility of different materials; improve the stability and reliability of the device, reduce energy consumption, and reduce maintenance requirements.

[0031] The parallel groove channels 19 of the device of the present invention are etched with microstructure arrays 20 such as microcones, microsquare columns, microcylinders and microelliptical columns, so that the uniformity of the flow field can be improved and the separation degree of each component of the analyte can be increased.

[0032] The separation material coated on the surface of the parallel groove channels 19 of the device of the present invention uses a dual stationary phase structure of superimposed polar and non-polar materials, so the separation module 6 has a high adsorption rate and a large separation speed for both polar and non-polar substances.

[0033] The detection module 7 of the device of the present invention is a sensor based on the principle of converting fluorescent chemical signals into electrical signals, so only an excitation light source 24, a fluorescent sensing unit 26 and a photosensitive component 25 are required to achieve extremely low-level non-destructive and rapid detection, without the need for a high-temperature heat source and necessary pure gas; at the same time, the analytes can be distinguished and identified based on the cross-complementary information of time-resolved response kinetics and retention time, thereby achieving accurate qualitative analysis.

[0034] The fluorescent sensing unit 26 of the device of the present invention adopts organic fluorescent material, so it only needs to be deposited in the parallel groove channel 19 at the outlet of the separation module 6 to realize the integrated separation and detection; at the same time, the fluorescent sensing unit is highly designable, and the core building blocks or assembly structure can be changed or adjusted according to specific needs, so as to realize both one-to-one detection and one-to-many / many-to-one detection.

[0035] The enrichment module of the device of the present invention uses multiple layers of adsorption materials, each layer of adsorption materials has different adsorption characteristics, so different types of analytes can be efficiently concentrated at the same time.

[0036] The power consumption of the sampling module of the device of the present invention is lower than 1600mW, and the device can operate stably for a long time.

[0037] In summary, compared with the traditional micro gas chromatography system, the separation and detection method of the present invention adopts the fluorescence × chromatography method, which can improve sensitivity, shorten analysis time, simplify operation steps, reduce detection costs, and broaden the scope of application. The micro integrated gas chromatography device of the present invention is significantly superior to the existing technology in terms of portability, analytical performance, data processing capability and environmental friendliness, and is suitable for in-situ, efficient and rapid gas analysis and monitoring in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a block diagram of the separation detection device of Example 1 of the present invention.

[0039] Figure 2 This is a block diagram of the separation detection device of Example 2 and Example 3 of the present invention.

[0040] Figure 3 It is a schematic diagram of the structure of the separation and detection device of Example 2 and Example 3 of the present invention.

[0041] Figure 4 It is a schematic diagram of the structure of the separation module of Example 2 and Example 3 of the present invention.

[0042] Figure 5 It is a schematic diagram of the structure of the detection module of Example 2 and Example 3 of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments and drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] Example 1

[0045] Reference Figure 1 A separation and detection method of a micro-integrated fluorescence gas chromatography comprises the following steps: introducing an analyte into an enrichment module and concentrating it by active adsorption; the concentrated analyte flows into a separation module through an automated injection module, is carried by a carrier gas and interacts with a stationary phase to achieve separation; the separated components are loaded into a detection module, diffuse-interact-desorb in an excited fluorescence sensitive unit, and then the radiation path of the fluorescence sensitive unit is changed; the detection module converts the dynamically changing fluorescence signal into an electrical signal, and after the electrical signal is denoised, amplified, and qualitatively and quantitatively analyzed, a chromatogram is generated and the concentration and type of each component are output.

[0046] Reference Figure 1The method adopts a micro-integrated fluorescence gas chromatography separation and detection device, comprising a shell 1, wherein an enrichment module 4, an injection module 5, a separation module 6, and a detection module 7 are arranged inside the shell 1; an analyte injection port and a carrier gas injection port are arranged at the upper end of the shell 1, the analyte injection port is connected to the inlet of the enrichment module 4, and the enrichment module 4 is used to pre-concentrate the analyte; the carrier gas injection port is connected to the first inlet of the injection module 5, the outlet of the enrichment module 4 is connected to the second inlet of the injection module 5, the outlet of the injection module 5 is connected to the inlet of the separation module 6, and the injection module 5 is used to provide airflow and drive the analyte or air into the separation module; the outlet of the separation module 6 is connected to the inlet of the detection module 7, the separation module 6 is used to separate the components in the mixed analyte, and the detection module 7 is used to detect the separated analyte components and concentrations.

[0047] The housing 1 of the device of the present invention is made of high-strength polymer or carbon fiber antistatic material that is breathable, waterproof, lightweight, impact-resistant, and vibration-proof, which is easy to carry and transport and ensures the safety of equipment and personnel. The housing 1 has two structures, handle type and table base type, which is convenient for adjusting the use mode of the device according to the test scenario.

[0048] Example 2

[0049] Reference Figure 2 A separation and detection method of a micro-integrated fluorescence gas chromatography comprises the following steps: introducing an analyte into an enrichment module and concentrating it by active adsorption, the concentrated analyte flows into a separation module through an automated injection module, is carried by a carrier gas and interacts with a stationary phase to achieve separation; the separated components are loaded into a detection module, and diffusion-interaction-desorption occurs in an excited fluorescence sensitive unit, thereby changing the radiation mode of the fluorescence sensitive unit; the detection module converts the dynamically changing fluorescence signal into an electrical signal and transmits it to a data processing system; after denoising, amplification, and qualitative and quantitative analysis of the electrical signal, a chromatogram is generated and the concentration and type of each component are output; the detected analyte is loaded into an exhaust gas processor, and green emissions are achieved through filtering and adsorption processes.

[0050] Reference Figure 2The above method adopts a micro-integrated fluorescence gas chromatography separation and detection device, which includes a shell 1, and an enrichment module 4, an injection module 5, a separation module 6, a detection module 7, a temperature control system 8, a data processing system 10 and an exhaust gas processor 9 are arranged inside the shell 1. The shell 1 is used to accommodate and protect the various components of the device. The upper end of the shell 1 is provided with an analyte injection port and a carrier gas injection port, and the lower end is provided with an exhaust gas processor 9; the analyte injection port is connected to the inlet of the enrichment module 4, and the enrichment module 4 is used to pre-concentrate the analyte; the carrier gas injection port is connected to the first inlet of the injection module 5, the outlet of the enrichment module 4 is connected to the second inlet of the injection module 5, the outlet of the injection module 5 is connected to the inlet of the separation module 6, and the injection module 5 is used to provide airflow and drive the analyte or carrier gas to enter the separation module; this embodiment uses air as the carrier gas, and does not require a bulky gas cylinder, which is conducive to portable detection; the outlet of the separation module 6 is connected to the inlet of the detection module 7, and the separation module 6 is used to separate the mixed The detection module 7 is used to detect the components and concentrations of the separated analytes; the signal output of the detection module 7 is connected to the signal input of the data processing system 10, and the data processing system 10 is used to receive and process the electrical signal generated by the detection module 7, and analyze, output and display the results of the analytes; the outlet of the detection module 7 is connected to the inlet of the exhaust gas processor 9, and the exhaust gas processor 9 is used to process the measured exhaust gas to reduce the impact on the environment; the separation module 6 and the detection module 7 are equipped with a temperature control system 8, and the temperature control system 8 is used to control the temperature of the separation module 6 and the detection module 7 to achieve effective separation of the analytes in the separation column and rapid desorption of the analytes in the fluorescent sensing unit.

[0051] Reference Figure 3 , Figure 4 The first inlet of the injection module 5 is the first air inlet 13, and the first air inlet 13 is passed through the first flowmeter 11 to introduce the carrier gas 3; the second inlet of the injection module 5 is the second air inlet 14, and the second air inlet 14 is connected to the outlet of the enrichment module 4 through the second flowmeter 18, and the analyte concentrated by the enrichment module 4 is loaded into the second air inlet 14 of the injection module 5 after desorption; the outlet of the injection module 5 is the air outlet 15, the inlet of the separation module 6 is the separation system inlet end 16, and the outlet of the separation module 6 is the separation system outlet end 17, the air outlet 15 is connected to the separation system inlet end 16, the second air inlet 14 is used to load the analyte 2, and the first air inlet 13 is used to load the carrier gas 3; the separation module 6 uses MEMS technology to etch a parallel groove channel 19 with a microstructure array 20 on a clean substrate 22, and a separation system inlet end 16 and a separation system outlet end 17 connected to both ends of the channel.

[0052] The housing 1 is made of SBS polymer material, which is easy to carry and transport and ensures the safety of equipment and personnel, so as to ensure that the device can operate stably in indoor / outdoor environments.

[0053] The housing 1 has two structures: a handle type and a table-based type, which is convenient for adjusting the use mode of the device according to the test scenario.

[0054] The adsorption material filled in the enrichment module 4 is porous silica.

[0055] The sample injection module 5 adjusts the split ratio of the first flow meter 11 and the second flow meter 18 according to different test requirements, has a power consumption of 1450 mW, and a volume of 1.8×1.5×2.0 cm 3 , can run continuously for a long time.

[0056] The inlet of the separation module 6 and the injection module 5 are arranged at one end of the parallel groove channel 19, and the outlet of the separation module 6 and the detection module 7 are arranged at the other end of the parallel groove channel 19. The parallel groove channel 19 and the cover plate 21 are packaged by silicon-silicon bonding process to ensure airtightness.

[0057] The parallel groove channels 19 are arranged in a square spiral shape.

[0058] The microstructure of the microstructure array 20 is micro-square pillars, which are used to improve the uniformity of the flow field and increase the separation degree of each component of the analyte.

[0059] The surface of the parallel groove channel 19 is coated with polyethylene glycol and dimethylsiloxane, so that the separation module 6 has a high adsorption rate and a large separation speed for both polar substances and non-polar substances.

[0060] The separation material of the dual stationary phase structure is uniformly modified on the surface of the parallel groove channels 19 and the microstructure array 20 through a dynamic coating and curing process.

[0061] Reference Figure 5 The detection module 7 is embedded in the exit of the separation module 6. The detection module 7 is a sensor based on the principle of converting fluorescent chemical signals into electrical signals, including an excitation light source 24, a fluorescent sensitive unit 26 and a photosensitive component 25. The light emitted by the excitation light source 24 irradiates the fluorescent sensitive unit 26, and the reflected light of the fluorescent sensitive unit 26 reaches the photosensitive component 25. The relative positions of the components are adjusted according to the exit of the separation module 6.

[0062] The excitation light source 24 is an LED lamp bead with a power consumption of 10-60 μW and a central wavelength that is the optimal excitation light band of the fluorescence sensitive unit 26. By controlling the divergence angle and spot area of ​​the excitation light source 24, the light intensity signal-to-noise ratio and excitation efficiency are improved.

[0063] Reference Figure 5 A bandpass filter 27 is disposed on one side of the excitation light source 24 , and its light transmission range is determined according to the Stokes shift of the fluorescence sensitive unit 26 .

[0064] The fluorescence sensitive unit 26 is made of organic fluorescent material, which is deposited in the parallel groove channel 19 at the outlet of the separation module 6, thereby realizing the integration of separation and detection.

[0065] The photosensitive component 25 adopts a PIN photodiode, a phototransistor or a photomultiplier tube to receive the light signal and amplify and convert it into an electrical signal.

[0066] Reference Figure 5 A filter 28 is disposed at the front end of the photosensitive component 25 to eliminate signal interference from the excitation light source 24 .

[0067] The temperature control system 8 is used to control the column temperature of the separation module 6 and the desorption temperature of the detection module 7 .

[0068] The adsorption material used in the tail gas processor 9 is activated carbon and B combination of materials to ensure environmental safety during operation.

[0069] The data processing system 10 includes an analysis unit, a communication unit and a display unit. The analysis unit processes the time-domain electrical signal and converts it into a digital signal of the concentration and type of each component of the analyte. The digital signal is sent to the display unit via the communication unit.

[0070] The communication unit uses a wired communication method.

[0071] The micro-integrated fluorescence gas chromatography separation and detection device comprises a power supply 12, which comprises a battery management circuit and a charging circuit. The battery management circuit is responsible for the charging, discharging and protection functions of the battery, and the charging circuit supports the USB charging function.

[0072] The micro-integrated fluorescence gas chromatography separation and detection device is manufactured by integrated molding without additional interfaces and pure gas cylinders, thereby ensuring air tightness while reducing the volume and weight of the device.

[0073] Example 3

[0074] In this embodiment, BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) is used as the analyte, and the perylene diimide derivative P-PBI is used as the fluorescence sensitive unit 26. The specific separation and detection method steps are as follows:

[0075] 200-300 mL of 100 ppb BTEX gas sample analytes were introduced into the enrichment module 4, using MOF-5 and Tenax TM The TA adsorption material concentrates the analyte; the enrichment module 4 is heated to 165-175°C within 2-5 seconds, and the concentrated analyte is desorbed by a heat pulse and then loaded into the separation module 6 by the injection module 5 at a flow rate of 10 mL / min;

[0076] In the separation module 6, nitrogen is used as the carrier gas 3 to load BTEX into the parallel groove channel 19, and each component repeatedly undergoes an adsorption / desorption process with the stationary phase therein; the stationary phase is polydimethylsiloxane with a thickness of 0.2 to 0.3 μm, and the component with a larger distribution coefficient has a shorter residence time in the stationary phase and moves faster, while the component with a smaller distribution coefficient has a longer residence time in the stationary phase, thereby achieving efficient separation of each component;

[0077] After separation, the BTEX analytes are sequentially loaded into the detection module 7 in the order of benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene, and diffuse, interact and desorb in the P-PBI of the excited state fluorescence sensitive unit 26, causing the fluorescence intensity of P-PBI to change dynamically over time; the detection module 7 captures the dynamic response changes of the fluorescence signal in real time, and converts it into a corresponding electrical signal and transmits it to the data processing system 10;

[0078] The data processing system 10 performs denoising and signal amplification on the collected electrical signals, performs qualitative and quantitative analysis based on the preset standard curve, generates a time domain chromatogram of each BTEX component, and outputs the type and concentration of each component. After the detection is completed, all analytes are introduced into the exhaust gas processor 9, and the activated carbon and The B combination of materials efficiently removes BTEX gas, ensuring that the exhaust gas meets environmental standards.

[0079] The difference between Example 3 and Example 2 is that: the enrichment module 4 is filled with a double-layer adsorption material for analytes of different polarities, so as to achieve efficient enrichment of all components; the heating desorption adopts micro-resistance heating technology, which can achieve rapid desorption of analytes in a short time; the separation module 6 includes a silicon substrate 22, an etched connected parallel groove channel 19 and a microstructure array 20 of cylinders etched in the channel. The pressure drop and eddy diffusion effect generated by the regular arrangement of the cylinders are smaller, so that the speed of each component of the analyte during the mass transfer process remains the same, avoiding band broadening; the excitation light source 24 of the detection module 7 adopts a 490nm patch-type excitation light source, the photosensitive component 25 adopts a 550nm filter and a photomultiplier tube, the detection module 7 has a built-in signal amplifier for enhancing the electrical signal, and the data processing system 10 is equipped with a touch screen operation interface, and the user can set parameters, process data and select and output results through the graphical interface.

[0080] In summary, the present invention describes a separation and detection method and device for miniature integrated fluorescence gas chromatography. Its innovation lies in the integrated, highly sensitive fluorescence detection and exhaust gas environmental protection treatment design. It can realize in-situ and rapid qualitative and quantitative detection of trace gases in complex environments. It is suitable for multiple fields and has significant technical advantages and market application potential.

[0081] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A separation and detection method of micro-integrated fluorescence gas chromatography, characterized in that: The following steps are involved: The analyte is introduced into the enrichment module and concentrated. The concentrated analyte flows into the separation module through the automated injection module, where it is carried by the carrier gas and interacts with the stationary phase to achieve separation. The separated components are loaded into the detection module, where they diffuse, interact, and desorb in the excited fluorescence sensitive unit, thereby changing the radiation path of the fluorescence sensitive unit. The detection module converts the dynamically changing fluorescence signal into an electrical signal. After analysis, the electrical signal generates a chromatogram and outputs the concentration and type of each component.

2. The separation and detection method according to claim 1, characterized in that: The fluorescent sensing unit is designable and is customized and synthesized according to the characteristics of the analyte. It is a combination of one or more organic fluorescent small molecules, fluorescent high molecular polymers and metal organic fluorescent complexes. The sensing mechanism of the fluorescent sensing unit is a combination of one or more of the energy transfer, specific binding / reaction and microenvironment disturbance mechanisms between the fluorescent sensing unit and the analyte. According to the relative positions of the excitation light source, the fluorescent sensing unit and the photosensitive component, the detection mode is transmission type, reflection type and diffuse reflection type.

3. A micro-integrated fluorescence gas chromatography separation and detection device, comprising a housing (1), characterized in that: An enrichment module (4), an injection module (5), a separation module (6) and a detection module (7) are arranged inside the shell (1); an analyte injection port and a carrier gas injection port are arranged at the upper end of the shell (1); the analyte injection port is connected to the inlet of the enrichment module (4), the carrier gas injection port is connected to the first inlet of the injection module (5), the outlet of the enrichment module (4) is connected to the second inlet of the injection module (5), the outlet of the injection module (5) is connected to the inlet of the separation module (6), and the outlet of the separation module (6) is connected to the inlet of the detection module (7).

4. The separation detection device according to claim 3, characterized in that: The signal output of the detection module (7) is connected to the signal input of the data processing system (10).

5. The separation detection device according to claim 3, characterized in that: The outlet of the detection module (7) is connected to the inlet of the exhaust gas processor (9).

6. The separation detection device according to claim 3, characterized in that: The separation module (6) and the detection module (7) are optionally equipped with a temperature control system (8).

7. The separation detection device according to claim 3, characterized in that: The first inlet of the injection module (5) is a first air inlet (13), and the first air inlet (13) is connected to the carrier gas (3) via a first flow meter (11); the second inlet of the injection module (5) is a second air inlet (14), and the second air inlet (14) is connected to the outlet of the enrichment module (4) via a second flow meter (18); the outlet of the injection module (5) is an air outlet (15), the inlet of the separation module (6) is an inlet end (16) of the separation system, the outlet of the separation module (6) is an outlet end (17) of the separation system, and the air outlet (15) is connected to the inlet end (16) of the separation system; the injection module (5) adjusts the split ratio of the first flow meter (11) and the second flow meter (18) according to different test requirements, and has the characteristics of low power consumption and miniaturization, with power consumption lower than 1600mW and a volume less than 8cm 3 .

8. The separation detection device according to claim 7, characterized in that: The separation module (6) uses MEMS technology to etch a connected parallel groove channel (19) having a microstructure array (20) on a substrate (22) and a separation system inlet end (16) and a separation system outlet end (17) connected to both ends of the channel; the parallel groove channel (19) adopts a square spiral, circular spiral or serpentine layout; the microstructure of the microstructure array (20) is one of a microcone, a microsquare column, a microcylinder or a microelliptical column; the inlet of the separation module (6) and the injection module (5) are arranged at one end of the parallel groove channel (19), the outlet of the separation module (6) and the detection module (7) are arranged at the other end of the parallel groove channel (19), and the parallel groove channel (19) and the cover plate (21) are packaged using a silicon-silicon bonding process.

9. The separation detection device according to claim 8, characterized in that: The surface of the separation module (6) is coated with a separation material, which uses a dual stationary phase structure of superimposed polar and non-polar materials, and is uniformly modified on the surface of the parallel groove channels (19) and the microstructure array (20) through a dynamic coating and curing process.

10. The separation detection device according to claim 3, characterized in that: The detection module (7) is embedded in the outlet of the separation module (6). The detection module (7) is a sensor based on the principle of converting fluorescent chemical signals into electrical signals, and includes an excitation light source (24), a fluorescent sensitive unit (26) and a photosensitive component (25). The relative positions of the components are adjusted according to the outlet of the separation module (6).

11. The separation detection device according to claim 10, characterized in that: The excitation light source (24) is an LED lamp bead with a power consumption of 10 to 60 μW and a central wavelength that is the optimal excitation light band of the fluorescence sensitive unit (26); a bandpass filter (27) is arranged on one side of the excitation light source (24), and its light transmission range is determined according to the Stokes shift of the fluorescence sensitive unit (26); the fluorescence sensitive unit (26) adopts an organic fluorescent material, which is deposited in a parallel groove channel (19) at the outlet of the separation module (6), thereby realizing the integration of separation and detection; the photosensitive component (25) adopts a PIN-type photodiode, a phototransistor or a photomultiplier tube, receives the light signal and amplifies and converts it into an electrical signal; and a filter (28) is arranged at the front end of the photosensitive component (25).

12. The separation detection device according to claim 4, characterized in that: The data processing system (10) comprises an analysis unit, a communication unit and a display unit. The analysis unit processes the time-domain electrical signal and converts it into a digital signal of the concentration and type of each component of the analyte, and the digital signal is sent to the display unit via the communication unit. The communication unit has a communication mode comprising at least one of the following: wired, Bluetooth, NFC, WIFI and mobile data. The display unit is a touch screen panel, or a screen panel equipped with an additional input unit.

13. The separation detection device according to any one of claims 3 to 12, characterized in that: The micro-integrated fluorescence gas chromatography separation and detection device is formed by 3D micro-machining, each module is arranged in a vertical stack or parallel arrangement structure, and the overall size of the device is less than 400cm 3 And achieve long-term operation powered by secondary batteries through low-power design.

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