Emulsified oil fluorescence intensity detection device based on integrated titanium metal micro-fluidic chip and preparation method

Abstract

The invention discloses an emulsified oil fluorescence intensity detection device based on an integrated titanium metal micro-fluidic chip. The emulsified oil fluorescence intensity detection device comprises an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device. The emulsified oil enrichment device comprises a micro-fluidic chip matrix group, a titanium foil filter membrane and a precise injection pump; the emulsified oil fluorescence intensity detection device comprises a fluorescence light source, a confocal light path, a photodiode and a photocurrent conversion circuit. The titanium foil filter membrane with underwater super-oleophobic property is processed by femtosecond laser, when emulsion passes through the titanium foil filter membrane, emulsified oil can be left in the emulsified oil enrichment chamber, emulsified oil enrichment and fluorescence intensity detection are completed in the area, and the device has the advantages of portability, high detection speed, easiness in operation, good real-time performance and the like, and is suitable for popularization and application. And the low-concentration emulsified oil in the marine environment can be quantified on site, and can be further analyzed by using a mass spectrometer in a laboratory environment, which may have wide significance.

Description

Technical Field

[0001] The present invention belongs to the field of micro-nano sensing and microfluidics. Specifically, the present invention relates to an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidics chip and a preparation method thereof. Background Art

[0002] Due to the frequent oil spills and discharge of industrial oily wastewater in metal processing, pharmaceutical manufacturing and oil and gas industries, the problem of water pollution caused by oil has attracted more and more attention. Generally, oil-water mixtures can be divided into two categories: immiscible oil-water mixtures and emulsified oil / water mixtures, and emulsified oil / water mixtures include oil-in-water (O / W) emulsions or water-in-oil (W / O) emulsions. For stratified oil-water mixtures, they can be separated naturally over time according to density. However, emulsified oil-water mixtures have always been considered to be stable colloidal dispersions, with micro-nano-scale droplets dispersed in an immiscible continuous phase. The presence of a strong oil-water interfacial film and adsorbed surfactant components determines its extremely stable performance. In addition, the small size of the emulsified droplets (usually less than 20 μm) also increases the difficulty of separation.

[0003] In the separation of emulsified oil / water mixtures, solvent extraction, microwave irradiation, oxidation, biomass, cryocoring, landfill, electrokinetics and reverse flotation have been used for the treatment of oily wastewater, but are limited by low efficiency and high cost. Membrane-based filtration technology stands out among various separation methods due to its high separation efficiency, good selectivity, low energy cost, environmental friendliness and wide industrial application.

[0004] Femtosecond laser is a promising tool for the ablation of micro / nanoscale hierarchical rough structures, with advantages such as non-contact manufacturing, small heat-affected zone, high precision and no pollution. It is a sophisticated means for the preparation of membrane-based filtration membranes.

[0005] Microfluidics is a science and technology that is mainly characterized by the precise manipulation of fluids in micro-nanoscale space. It has the ability to miniaturize the basic functions of biological and chemical laboratories such as sample preparation, reaction, separation and detection onto a chip of a few square centimeters. Its basic characteristics and greatest advantage are the flexible combination and large-scale integration of multiple unit technologies on an overall controllable micro-platform. It is an interdisciplinary technology involving engineering, physics, chemistry, micro-machining and bioengineering. As a new type of biosensor tool, microfluidic chips can be used for processing to meet the needs of various research fields. The size of the chip matches the size of the micron-scale emulsified oil, so it is suitable for emulsified oil enrichment and has a high application value in oil spill pollution detection.

[0006] Most commercial portable ultraviolet (UV) fluorimeter for oil detection use the natural fluorescent fingerprint of crude oil, excited by UV light, but have limited sensitivity (usually at 0.05-1ppm). To detect oil droplets in the ppm range, complex flow chambers and expensive optical instruments are required, making them unsuitable for field deployment. Therefore, a low-cost, portable, and highly sensitive system that can quantify low-concentration oil droplets in the marine environment in the field or further analyze them using a mass spectrometer in a laboratory setting could be of broad interest.

[0007] The present invention combines a microfluidic chip using membrane-based filtration technology with a portable emulsified oil fluorescence intensity detection device, which is expected to solve the current dilemma. Summary of the invention

[0008] The purpose of the present invention is to solve the problem of being able to quantify low-concentration oil droplets in a marine environment on site, and to provide an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip, and a preparation method.

[0009] To achieve the above purpose, the technical solution provided by the present invention is:

[0010] An emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip comprises an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device; wherein,

[0011] The emulsified oil enrichment device comprises a microfluidic chip substrate group 1, a titanium foil filter membrane 11, a first precision injection pump 15, a second precision injection pump 16 and a waste liquid collector 14; the microfluidic chip substrate group 1 comprises a first layer of PDMS substrate 10 and a second layer of PDMS substrate 13; the titanium foil filter membrane 11 is located between the first layer of PDMS substrate 10 and the second layer of PDMS substrate 13;

[0012] The first layer of PDMS substrate 10 is provided with an emulsion inlet pipe 2, a columnar array 3, a symmetrical bending channel 4, an emulsified oil enrichment chamber 7, a filtrate outlet pipe 9, a cleaning liquid inlet pipe 5, a cleaning liquid flushing channel 6, and a cleaning liquid outlet pipe 8; the second layer of PDMS substrate 13 includes a filtrate discharge channel 12; the first precision injection pump 15 is connected to the emulsion inlet pipe 2; the second precision injection pump 16 is connected to the cleaning liquid inlet pipe 5; the waste liquid collector 14 is connected to the cleaning liquid outlet pipe 8 and the filtrate outlet pipe 9;

[0013] The emulsified oil fluorescence intensity detection device comprises a fluorescent light source 171, a fluorescent optical path component, a photodiode 174 and a photocurrent conversion circuit board. After the light emitted from the fluorescent light source 171 passes through the fluorescent optical path component and the outgoing light spot irradiates the emulsified oil enrichment chamber 7, the photodiode 174 on the photocurrent conversion circuit board collects the light and feeds it back to the host computer for analysis; wherein,

[0014] The fluorescent light path assembly includes, according to the direction of the light path, a fluorescent light source 171, a first lens 172, a first filter 173, a dichroic mirror 177, a second lens 178, a second filter 176, a third lens 175, and a photodiode 174.

[0015] The incident light of the fluorescent light source 171 is focused by the first lens 172, and the first filter 173 realizes short-wave pass filtering of 250 to 400 nm. The light source of 370 to 400 nm is reflected by the dichroic mirror 177, and is focused on the emulsified oil enrichment chamber 7 of the first layer of PDMS substrate 10 through the second lens 178. The emulsified oil enriched here produces a fluorescence effect after being irradiated by the light source. The generated stray light and fluorescence are collected by the second lens 178, and are long-pass filtered by the dichroic mirror 177 and the second filter 176. The fluorescence of 420 to 1200 nm is focused on the photodiode 174 through the third lens 175. The photocurrent generated by the photodiode 174 is collected by the current conversion circuit board and converted into a voltage signal through multi-stage amplification. The conversion of the voltage signal to the fluorescence intensity is completed by linear fitting and experimental calibration.

[0016] The preferred technical solution provided by the present invention is:

[0017] The titanium foil filter membrane 11 has a linear slit array 111 processed by a femtosecond laser system. The linear slit array has at least 40 linear slits. The linear length of the linear slits is 8 mm, and the spacing between each linear slit is 20 μm.

[0018] The further preferred technical solution provided by the present invention is:

[0019] The specific processing process of the femtosecond laser processing system is as follows:

[0020] In the laser processing optical path, the laser energy and laser frequency are set in the femtosecond laser control system, the femtosecond laser 182 is controlled to generate a laser light source, the optical path conversion is completed through the femtosecond laser processing lens 181, and the laser is focused on the titanium foil filter membrane 11 placed on the high-precision displacement stage 184 through the 50x magnification lens 183. By controlling the movement of the high-precision displacement stage 184, the processing of the linear slit array 111 is realized; in the imaging optical path, the light of the illumination light source 186 passes through the optical path and irradiates the titanium foil filter membrane 11 to be processed, the reflected light is collected by CCD185, and the processing process is observed in real time on the host computer.

[0021] More preferably,

[0022] The laser energy of the femtosecond laser processing system is 1.5W~1.8W, the laser frequency is 800Hz~1200Hz, and the moving speed of the high-precision translation stage is 0.05mm / s~0.09mm / s. The prepared processing material is placed on the high-precision translation stage 184, the high-precision translation stage 184 is controlled to focus, and the focusing effect is observed through CCD185.

[0023] Preferably, the fluorescent light source 171 is UVB310nm LED.

[0024] The present invention also provides a method for preparing an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip, comprising the following steps:

[0025] S1: Preparation of titanium foil filter membrane;

[0026] S10, build the femtosecond laser processing system and write the processing program code;

[0027] S11, preparation process of processing materials;

[0028] Use scissors to cut the titanium foil with a thickness of 10 to 30 μm into a rectangular titanium foil corresponding to the size of the top view of the microfluidic chip substrate group 1, and fix it on a high-precision displacement stage after flattening;

[0029] S12, femtosecond laser preparation of titanium foil filter membrane 11;

[0030] The laser energy is controlled to be 1.5W-1.8W, the laser frequency is 800Hz-1200Hz, and the moving speed of the high-precision translation stage is 0.05mm / s-0.09mm / s. The processing material prepared in step S11 is placed on the high-precision translation stage 184, and the high-precision translation stage 184 is controlled to focus. The focusing effect is observed through CCD185, and the processing program is started for processing;

[0031] S2: preparation of microfluidic chip substrate group;

[0032] S20, use Autocad software to draw the film template;

[0033] S21, soft lithography, spreading Su8-3035 photoresist on the entire silicon wafer through a coating machine, and under the light-induced cross-linking action of a UV lithography machine, the pattern with a channel structure on the film plate is engraved on the silicon substrate;

[0034] S22, use PDMS for molding, mix PDMS and curing agent in a ratio of 10:1, remove the internal bubbles and heat and mold on a silicon substrate to form a microfluidic chip; the height of the chip channel is 70μm, and the overall length of the chip is 2.4cm and the width is 1.8cm.

[0035] S3: Sealing of microfluidic chip;

[0036] Cut a double-sided tape of the same size as the first PDMS substrate 10, and use a hole puncher with a diameter of 1 mm to make holes so that the punching position is aligned with the emulsified oil enrichment chamber 7 of the first PDMS substrate 10, thereby completing the sealing of the first PDMS substrate 10 and the titanium foil filter membrane 11;

[0037] Repeat the above steps to complete the sealing of the second PDMS substrate 13 and the titanium foil filter membrane 11 in the same way;

[0038] S4: Construction of emulsified oil enrichment device and connection of emulsion inlet device;

[0039] A first precision injection pump 15 is connected to the emulsion inlet pipe 2 in the microfluidic chip by a hose, and a second precision injection pump 16 is connected to the cleaning liquid inlet pipe 5 in the microfluidic chip by a hose;

[0040] The connection of the waste liquid collection device is to connect the port A of the waste liquid collection device and the cleaning liquid outlet pipe 8 in the microfluidic chip with a hose, and to connect the port B of the waste liquid collection device and the filtrate outlet pipe 9 in the microfluidic chip with a hose;

[0041] S5: Construction of the fluorescence intensity detection device for emulsified oil;

[0042] Use SOLIDWORKS to draw the 3D model of the shell of the emulsified oil fluorescence intensity detection device, and use 3D printing technology to prepare the 3D model of the shell of the emulsified oil fluorescence intensity detection device, the material is black nylon;

[0043] Use AltiumDesigner to draw the photocurrent conversion circuit and make the PCB board;

[0044] Install the fluorescent light source 171 at the fluorescent light source installation position 1710 of the housing of the emulsified oil fluorescence intensity detection device; install the fluorescent light path component at the fluorescent light path component installation position 1711 of the housing of the emulsified oil fluorescence intensity detection device; install the photodiode 174 at the photodiode installation position 1712 of the housing of the emulsified oil fluorescence intensity detection device; install the current conversion circuit at the photocurrent conversion circuit installation position 1713 of the emulsified oil fluorescence intensity detection device;

[0045] S6: assembly of an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device;

[0046] A microfluidic chip is placed at position 179 of the housing of the emulsified oil fluorescence intensity detection device, so that the emulsified oil enrichment chamber 7 in the microfluidic chip is aligned with the output light spot of the emulsified oil fluorescence intensity detection device.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1. The designed microfluidic chip with integrated titanium foil filter membrane can not only quantify low-concentration oil droplets in the marine environment on site, but also further analyze them using a mass spectrometer in a laboratory environment.

[0049] 2. The designed emulsified oil fluorescence intensity detection device is low-cost and highly portable, making it possible to quantify low-concentration oil droplets in the marine environment on site. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0051] Figure 2 Schematic diagram of femtosecond laser processing of titanium foil filter membrane;

[0052] Figure 3 This is a schematic diagram of the optical path construction of the emulsified oil fluorescence detection device;

[0053] Figure 4 Schematic diagram of photocurrent conversion circuit;

[0054] Figure 5 This is a schematic diagram of the optical path of femtosecond laser processing;

[0055] Figure 6 This is a film template image for preparing a microfluidic chip substrate group;

[0056] Figure 6 a is the first layer PDMS substrate film template image, Figure 6 b is the template image of the second layer PDMS substrate film plate;

[0057] Figure 7This is a 3D model diagram of the emulsified oil fluorescence intensity detection device;

[0058] In the figure: 1, microfluidic chip substrate group; 2, emulsion inlet pipeline; 3, columnar array; 4, symmetrical bending channel; 5, cleaning liquid inlet pipeline; 6, cleaning liquid flushing channel; 7, emulsified oil enrichment chamber; 8, cleaning liquid outlet pipeline; 9, filtrate outlet pipeline; 10, first layer PDMS substrate; 11, titanium foil filter membrane; 12, filtrate discharge channel; 13, second layer PDMS substrate; 14, waste liquid collector; 15, precision injection pump 1; 16, precision injection pump 2; 17, emulsified oil fluorescence intensity detection device; 111, linear gap array; 171, fluorescence Light source; 172, lens 1; 173, filter 1; 174, ; 175, lens 2; 176, filter 2; 177, dichroic mirror; 178, lens 3; 179, microfluidic chip installation position; 1710, fluorescent light source installation position; 1711, fluorescent light path component installation position; 1712, photodiode installation position; 1713, photocurrent conversion circuit installation position; 181, femtosecond laser processing lens; 182, femtosecond laser; 183, 50x magnification mirror; 184, high-precision translation stage; 185, CCD; 186, illumination light source. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings.

[0060] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0061] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0063] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0064] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0065] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0066] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0067] The present invention discloses an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip, comprising an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device; wherein:

[0068] like Figure 1 As shown, the emulsified oil enrichment device includes a microfluidic chip substrate group 1, a titanium foil filter membrane 11, a first precision injection pump 15, a second precision injection pump 16 and a waste liquid collector 14; the microfluidic chip substrate group 1 includes a first layer of PDMS substrate 10 and a second layer of PDMS substrate 13; the titanium foil filter membrane 11 is located between the first layer of PDMS substrate 10 and the second layer of PDMS substrate 13;

[0069] The first layer of PDMS substrate 10 is provided with an emulsion inlet pipe 2, a columnar array 3, a symmetrical bending channel 4, an emulsified oil enrichment chamber 7, a filtrate outlet pipe 9, a cleaning liquid inlet pipe 5, a cleaning liquid flushing channel 6, and a cleaning liquid outlet pipe 8; the second layer of PDMS substrate 13 includes a filtrate discharge channel 12; the first precision injection pump 15 is connected to the emulsion inlet pipe 2; the second precision injection pump 16 is connected to the cleaning liquid inlet pipe 5; the waste liquid collector 14 is connected to the cleaning liquid outlet pipe 8 and the filtrate outlet pipe 9;

[0070] like Figure 3As shown, the emulsified oil fluorescence intensity detection device of the present invention comprises a fluorescent light source 171, a fluorescent light path component, a photodiode 174 and a photocurrent conversion circuit board. After the light emitted from the fluorescent light source 171 passes through the fluorescent light path component and irradiates the emulsified oil enrichment chamber 7, the photodiode 174 on the photocurrent conversion circuit board collects the light and feeds it back to the host computer for analysis; the fluorescent light source 171 is a UVB310nmLED. Among them, the photocurrent conversion circuit board is as follows: Figure 4 as shown in .

[0071] in,

[0072] The fluorescent light path assembly includes, according to the direction of the light path, a fluorescent light source 171, a first lens 172, a first filter 173, a dichroic mirror 177, a second lens 178, a second filter 176, a third lens 175, and a photodiode 174.

[0073] The incident light of the fluorescent light source 171 is focused by the first lens 172, and the first filter 173 realizes short-wave pass filtering of 250 to 400 nm. The light source of 370 to 400 nm is reflected by the dichroic mirror 177, and is focused on the emulsified oil enrichment chamber 7 of the first layer of PDMS substrate 10 through the second lens 178. The emulsified oil enriched here produces a fluorescence effect after being irradiated by the light source. The generated stray light and fluorescence are collected by the second lens 178, and are long-pass filtered by the dichroic mirror 177 and the second filter 176. The fluorescence of 420 to 1200 nm is focused on the photodiode 174 through the third lens 175. The photocurrent generated by the photodiode 174 is collected by the current conversion circuit board and converted into a voltage signal through multi-stage amplification. The conversion of the voltage signal to the fluorescence intensity is completed by linear fitting and experimental calibration.

[0074] Among them, combined Figure 2 As shown, the titanium foil filter membrane 11 of the present invention has a linear slit array 111 processed by a femtosecond laser system, the linear slit array has at least 40 linear slits, the linear length of the linear slits is 8 mm, and the spacing between each linear slit is 20 μm.

[0075] Among them, combined Figure 5 As shown in , the specific processing process of the femtosecond laser processing system is as follows:

[0076] In the laser processing optical path, the laser energy and laser frequency are set in the femtosecond laser control system, and the femtosecond laser 182 is controlled to generate a laser light source. The optical path conversion is completed through a series of femtosecond laser processing lenses 181, and the laser is focused on the titanium foil filter membrane 11 placed on the high-precision displacement stage 184 through a 50x magnification lens 183. By controlling the movement of the high-precision displacement stage 184, the processing of the linear slit array 111 is realized; in the imaging optical path, the light of the illumination light source 186 passes through the optical path and irradiates the titanium foil filter membrane 11 to be processed, and the reflected light is collected by CCD185, and the processing process is observed in real time on the host computer.

[0077] The laser energy of the femtosecond laser processing system is 1.5W~1.8W, the laser frequency is 800Hz~1200Hz, and the moving speed of the high-precision translation stage is 0.05mm / s~0.09mm / s. The prepared processing material is placed on the high-precision translation stage 184, the high-precision translation stage 184 is controlled to focus, and the focusing effect is observed through CCD185.

[0078] The present invention also provides a method for preparing an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip, comprising the following steps:

[0079] S1: Preparation of titanium foil filter membrane;

[0080] S10, build as Figure 5 The femtosecond laser processing system and the coding of the processing program shown;

[0081] S11, preparation process of processing materials;

[0082] Use scissors to cut the titanium foil with a thickness of 10 to 30 μm into a rectangular titanium foil corresponding to the size of the top view of the microfluidic chip substrate group, use a rubber hammer to repeatedly hammer it on a flat steel plate to make it flat, and use tape to fix it on a high-precision displacement stage;

[0083] S12, femtosecond laser preparation of titanium foil filter membrane 11;

[0084] The laser energy is controlled to be 1.5W-1.8W, the laser frequency is 800Hz-1200Hz, and the moving speed of the high-precision translation stage is 0.05mm / s-0.09mm / s. The processing material prepared in step S11 is placed on the high-precision translation stage 184, and the high-precision translation stage 184 is controlled to focus. The focusing effect is observed through CCD185, and the processing program is started for processing;

[0085] S2: preparation of microfluidic chip substrate group;

[0086] S20, use Autocad software to draw the film template, such as Figure 6As shown in Figure 6 a is the first layer PDMS substrate film template image, Figure 6 b is the template image of the second layer PDMS substrate film plate;

[0087] S21, soft lithography, spreading Su8-3035 photoresist on the entire silicon wafer through a coating machine, and under the light-induced cross-linking action of a UV lithography machine, the pattern with a channel structure on the film plate is engraved on the silicon substrate;

[0088] S22, use PDMS for molding, mix PDMS and curing agent in a ratio of 10:1, remove the internal bubbles and heat and mold on a silicon substrate to form a microfluidic chip; the height of the chip channel is 70μm, and the overall length of the chip is 2.4cm and the width is 1.8cm.

[0089] S3: Sealing of microfluidic chip;

[0090] Cut a double-sided tape of the same size as the first PDMS substrate 10, and use a hole puncher with a diameter of 1 mm to make holes so that the punching position is aligned with the emulsified oil enrichment chamber 7 of the first PDMS substrate 10, thereby completing the sealing of the first PDMS substrate 10 and the titanium foil filter membrane 11;

[0091] Repeat the above steps to complete the sealing of the second PDMS substrate 13 and the titanium foil filter membrane 11 in the same way;

[0092] S4: Construction of emulsified oil enrichment device and connection of emulsion inlet device;

[0093] A first precision injection pump 15 is connected to the emulsion inlet pipe 2 in the microfluidic chip by a hose, and a second precision injection pump 16 is connected to the cleaning liquid inlet pipe 5 in the microfluidic chip by a hose;

[0094] The connection of the waste liquid collection device is to connect the port A of the waste liquid collection device and the cleaning liquid outlet pipe 8 in the microfluidic chip with a hose, and to connect the port B of the waste liquid collection device and the filtrate outlet pipe 9 in the microfluidic chip with a hose;

[0095] S5: Construction of the fluorescence intensity detection device for emulsified oil;

[0096] Use SOLIDWORKS to draw the 3D model of the shell of the emulsified oil fluorescence intensity detection device, and use 3D printing technology to prepare the 3D model of the shell of the emulsified oil fluorescence intensity detection device, the material is black nylon;

[0097] Use AltiumDesigner to draw the photocurrent conversion circuit and make the PCB board;

[0098] The fluorescent light source 171, the fluorescent light path component, the photodiode 174 and the photocurrent conversion circuit are installed on the housing of the emulsified oil fluorescence intensity detection device. Figure 7 Specifically, the fluorescent light source 171 is installed at the fluorescent light source installation position 1710 of the housing position of the emulsified oil fluorescence intensity detection device; the fluorescent light path component is installed at the fluorescent light path component installation position 1711 of the housing position of the emulsified oil fluorescence intensity detection device; the photodiode 174 is installed at the photodiode installation position 1712 of the housing position of the emulsified oil fluorescence intensity detection device; the current conversion circuit is installed at the photocurrent conversion circuit installation position 1713 of the emulsified oil fluorescence intensity detection device;

[0099] S6: assembly of an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device;

[0100] A microfluidic chip is placed at position 179 of the housing of the emulsified oil fluorescence intensity detection device, so that the emulsified oil enrichment chamber 7 in the microfluidic chip is aligned with the output light spot of the emulsified oil fluorescence intensity detection device. The fluorescence generated by the emulsified oil passes through Figure 3 The optical path shown is filtered by Figure 4 The photocurrent conversion circuit shown converts the photocurrent into fluorescence intensity value to complete the detection.

[0101] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip, characterized in that: It includes an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device; wherein, The emulsified oil enrichment device comprises a microfluidic chip substrate group (1), a titanium foil filter membrane (11), a first precision injection pump (15), a second precision injection pump (16) and a waste liquid collector (14); the microfluidic chip substrate group (1) comprises a first layer of PDMS substrate (10) and a second layer of PDMS substrate (13); the titanium foil filter membrane (11) is located between the first layer of PDMS substrate (10) and the second layer of PDMS substrate (13); The first layer of PDMS substrate (10) is provided with an emulsion inlet pipeline (2), a columnar array (3), a symmetrical bending channel (4), an emulsified oil enrichment chamber (7), a filtrate outlet pipeline (9), a cleaning liquid inlet pipeline (5), a cleaning liquid flushing channel (6), and a cleaning liquid outlet pipeline (8); the second layer of PDMS substrate (13) includes a filtrate discharge channel (12); the first precision injection pump (15) is connected to the emulsion inlet pipeline (2); the second precision injection pump (16) is connected to the cleaning liquid inlet pipeline (5); the waste liquid collector (14) is connected to the cleaning liquid outlet pipeline (8) and the filtrate outlet pipeline (9); The emulsified oil fluorescence intensity detection device comprises a fluorescent light source (171), a fluorescent light path component, a photodiode (174) and a photocurrent conversion circuit board. After the light emitted by the fluorescent light source (171) passes through the fluorescent light path component and irradiates the emulsified oil enrichment chamber (7), the photodiode (174) on the photocurrent conversion circuit board collects the light and feeds it back to the host computer for analysis; wherein, The fluorescent light path component includes, in the direction of the light path, a fluorescent light source (171), a first lens (172), a first filter (173), a dichroic mirror (177), a second lens (178), a second filter (176), a third lens (175), and a photodiode (174). The incident light of the fluorescent light source (171) is focused by the first lens (172), the first filter (173) realizes short-wave pass filtering of 250-400 nm, the light source of 370-400 nm is reflected by the dichroic mirror (177), and is focused on the emulsified oil enrichment chamber (7) of the first PDMS substrate (10) through the second lens (178), the emulsified oil enriched therein generates a fluorescence effect after being irradiated by the light source, the generated stray light and fluorescence are collected by the second lens (178), the dichroic mirror (177) and the second filter (176) perform long-pass filtering, and the fluorescence of 420-1200 nm is focused on the photodiode (174) through the third lens (175), the photocurrent generated by the photodiode (174) is collected by the current conversion circuit board and converted into a voltage signal through multi-stage amplification, and the conversion of the voltage signal to the fluorescence intensity is completed by linear fitting and experimental calibration.

2. The emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip according to claim 1, characterized in that: The titanium foil filter membrane (11) has a linear slit array (111) processed by a femtosecond laser system, the linear slit array has at least 40 linear slits, the linear length of the linear slits is 8 mm, and the spacing between each linear slit is 20 μm.

3. The emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip according to claim 2, characterized in that: The specific processing process of the femtosecond laser processing system is as follows: In the laser processing optical path, the laser energy and laser frequency are set in the femtosecond laser control system, the femtosecond laser (182) is controlled to generate a laser light source, the optical path conversion is completed through the femtosecond laser processing lens (181), and the laser is focused on the titanium foil filter membrane (11) placed on the high-precision displacement stage (184) through a 50x magnification mirror (183), and the linear slit array (111) is processed by controlling the movement of the high-precision displacement stage (184); in the imaging optical path, the light of the illumination light source (186) passes through the optical path and irradiates the titanium foil filter membrane (11) to be processed, the reflected light is collected by the CCD (185), and the processing process is observed in real time on the host computer.

4. The emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip according to claim 3, characterized in that: The laser energy of the femtosecond laser processing system is 1.5W-1.8W, the laser frequency is 800Hz-1200Hz, and the moving speed of the high-precision displacement stage is 0.05mm / s-0.09mm / s. The prepared processing material is placed on the high-precision displacement stage (184), the high-precision displacement stage (184) is controlled to focus, and the focusing effect is observed through the CCD (185).

5. The device for detecting fluorescence intensity of emulsified oil based on an integrated titanium metal microfluidic chip according to claim 1, characterized in that: The fluorescent light source (171) is a UVB310nm LED.

6. A method for preparing an emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip as claimed in any one of claims 1 to 5, characterized in that: The steps include: S1: Preparation of titanium foil filter membrane; S10, build the femtosecond laser processing system and write the processing program code; S11, preparation process of processing materials; Use scissors to cut the titanium foil with a thickness of 10 to 30 μm into rectangular titanium foil corresponding to the size of the top view of the microfluidic chip substrate group (1), and fix it on a high-precision displacement stage after flattening; S12, femtosecond laser preparation of titanium foil filter membrane (11); Controlling the laser energy to 1.5W-1.8W, the laser frequency to 800Hz-1200Hz, and the moving speed of the high-precision translation stage to 0.05mm / s-0.09mm / s, placing the processing material prepared in step S11 on the high-precision translation stage (184), controlling the high-precision translation stage (184) to focus, observing the focusing effect through the CCD (185), and starting the processing program to perform processing; S2: preparation of microfluidic chip substrate group; S20, use Autocad software to draw the film template; S21, soft lithography, spreading Su8-3035 photoresist on the entire silicon wafer through a coating machine, and under the light-induced cross-linking action of a UV lithography machine, the pattern with a channel structure on the film plate is engraved on the silicon substrate; S22, using PDMS for molding, mixing PDMS and curing agent in a ratio of 10:1, removing internal bubbles, and then heating and molding on a silicon substrate to form a microfluidic chip; S3: Sealing of microfluidic chip; Cut a double-sided tape of the same size as the first layer of PDMS substrate (10), and use a hole puncher with a diameter of 1 mm to make holes so that the punching position is aligned with the emulsified oil enrichment chamber (7) of the first layer of PDMS substrate (10), thereby completing the sealing of the first layer of PDMS substrate (10) and the titanium foil filter membrane (11); Repeat the above steps to similarly complete the sealing of the second layer of PDMS substrate (13) and the titanium foil filter membrane (11); S4: Construction of emulsified oil enrichment device and connection of emulsion inlet device; A first precision injection pump (15) is connected to an emulsion inlet pipe (2) in the microfluidic chip by using a hose, and a second precision injection pump (16) is connected to a cleaning liquid inlet pipe (5) in the microfluidic chip by using a hose; The waste liquid collection device is connected by using a hose to connect the port A of the waste liquid collection device and the cleaning liquid outlet pipe (8) in the microfluidic chip, and the port B of the waste liquid collection device and the filtrate outlet pipe (9) in the microfluidic chip; S5: Construction of the fluorescence intensity detection device for emulsified oil; Use SOLIDWORKS to draw the 3D model of the shell of the emulsified oil fluorescence intensity detection device, and use 3D printing technology to prepare the 3D model of the shell of the emulsified oil fluorescence intensity detection device, the material is black nylon; Use AltiumDesigner to draw the photocurrent conversion circuit and make the PCB; A fluorescent light source (171) is installed at a fluorescent light source installation position (1710) of the housing of the emulsified oil fluorescence intensity detection device; a fluorescent light path component is installed at a fluorescent light path component installation position (1711) of the housing of the emulsified oil fluorescence intensity detection device; a photodiode (174) is installed at a photodiode installation position (1712) of the housing of the emulsified oil fluorescence intensity detection device; and a current conversion circuit is installed at a photocurrent conversion circuit installation position (1713) of the emulsified oil fluorescence intensity detection device; S6: assembly of an emulsified oil enrichment device and an emulsified oil fluorescence intensity detection device; A microfluidic chip is placed at the housing position (179) of the emulsified oil fluorescence intensity detection device, so that the emulsified oil enrichment chamber (7) in the microfluidic chip is aligned with the output light spot of the emulsified oil fluorescence intensity detection device.

7. The method for preparing the emulsified oil fluorescence intensity detection device based on an integrated titanium metal microfluidic chip according to claim 6, characterized in that: In the step S22, the height of the chip channel of the microfluidic chip is 70 μm, and the length of the entire chip is 2.4 cm and the width is 1.8 cm.

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