Micro-fluidic chip device and optical tweezers experiment method

Abstract

The invention discloses a micro-fluidic chip device and an optical tweezers experimental method.The micro-fluidic chip device comprises a micro-fluidic chip, the micro-fluidic chip is provided with at least one inflow channel and at least one outflow channel, the micro-fluidic chip is provided with an optical tweezers control and imaging area, the inflow channel is communicated with the outflow channel through a fluid converging structure, and the outflow channel is communicated with the optical tweezers control and imaging area; the fluid convergence structure is at least partially located in the optical tweezers control and imaging area; the chip holder can be fixed in the optical tweezers system through the mounting structure, the chip holder is further provided with a clamping structure, at least one fluid access port and at least one fluid access port, the micro-fluidic chip is clamped and fixed by the clamping structure, the inflow channel is communicated with the corresponding fluid access port, and the fluid access port is communicated with the corresponding outflow channel. According to the invention, the positioning accuracy of the micro-fluidic chip in an optical tweezers system and the stability of the micro-fluidic chip in an optical tweezers experiment can be ensured, so that the capture efficiency and the imaging effect in the optical tweezers experiment are improved, and the repeatability of a measurement result is improved.

Description

Technical Field

[0001] The invention relates to the fields of microfluidic technology, optical tweezers technology and biomedical engineering technology, and in particular to a microfluidic chip device and an optical tweezers experimental method. Background Art

[0002] Optical tweezers are a special tool based on the momentum transfer between light and matter. They can capture and manipulate micro-nano sized particles and measure piconewton (pN) force. This non-contact, non-destructive manipulation of nanoparticles plays an irreplaceable role in the research of biology, materials, mechanics, chemistry, environment and other multidisciplinary fields, while also placing higher demands on research techniques and methods.

[0003] Microfluidic chip, also known as Lab on a Chip, is a micro-electromechanical technology based on multi-dimensional network microfluidic channel structure features, which can transfer and integrate the operation steps of chemical or biological sample collection, reaction, preparation, detection and so on into chip materials. In recent years, microfluidic technology has been widely used in cell sorting, cell biochemical reaction, single cell analysis and other research in combination with fluorescence, electrochemistry, Raman spectroscopy and other detection methods.

[0004] However, when existing microfluidic chips are used in optical tweezers systems, due to differences in the design and construction of optical tweezers systems in different laboratories, researchers are required to make their own sample chambers in most cases. It is difficult to find unified standards or detailed production methods, which increases the difficulty of conducting such optical tweezers experiments in non-professional fields. In addition, since homemade sample chambers are usually simple in structure, they are often used in situations such as sample deposition and adhesion, agglomeration, liquid overflow or too rapid loss, complex experimental environment, and inability to achieve single control, which in turn leads to problems such as low optical tweezers capture efficiency, poor repeatability of experimental results, and inability to reuse sample chambers. Summary of the invention

[0005] The purpose of the present invention is to provide a microfluidic chip device and an optical tweezers experimental method to solve the technical problems of low capture efficiency, poor imaging effect and difficult to repeat measurement results when the current sample chamber is used in an optical tweezers system for optical tweezers experiments.

[0006] The above-mentioned purpose of the present invention can be achieved by adopting the following technical solutions:

[0007] The present invention provides a microfluidic chip device, comprising: a microfluidic chip, provided with at least one inflow channel and at least one outflow channel, the microfluidic chip having an optical tweezers manipulation and imaging area, the inflow channel being connected to the outflow channel through a fluid confluence structure, and the fluid confluence structure being at least partially located in the optical tweezers manipulation and imaging area; a chip clamp, which can be fixed in an optical tweezers system through a mounting structure, the chip clamp also being provided with a clamping structure, at least one fluid access port and at least one fluid access port, the microfluidic chip being clamped and fixed by the clamping structure, and the inflow channel being connected to the corresponding fluid access port, and the fluid access port being connected to the corresponding outflow channel.

[0008] In an embodiment of the present invention, the microfluidic chip is made of high-transmittance optical glass; the thickness of the microfluidic chip is less than or equal to 1.35 mm.

[0009] In an embodiment of the present invention, the microfluidic chip includes a chip substrate and a chip cover, and the chip cover is bonded to the chip substrate; wherein, the lower surface of the chip cover is provided with at least one groove, and the upper surface of the chip cover is provided with at least one fluid outlet and at least one fluid inlet, the groove connects the fluid outlet and the fluid inlet, and the groove cooperates with the upper surface of the chip substrate to form the outflow channel and the inflow channel; and / or the upper surface of the chip substrate is provided with at least one groove, and the chip cover is provided with at least one fluid outlet and at least one fluid inlet, the groove connects the fluid outlet and the fluid inlet, and the groove cooperates with the lower surface of the chip cover to form the outflow channel and the inflow channel.

[0010] In an embodiment of the present invention, the number of the inflow channels is at least three; the fluid confluence structure includes at least three connecting channels corresponding to the at least three inflow channels and a confluence channel connecting at least three connecting channels with the outflow channel, and the width of the confluence channel is greater than the width of each of the inflow channels.

[0011] In an embodiment of the present invention, the outflow channel and the inflow channel are both provided in plurality, and the fluid confluence structure includes a plurality of connection structures, a plurality of connection channels and a confluence channel, the connection structure connects the corresponding inflow channel and the outflow channel, and the connection structure connects the confluence channel through the corresponding connection channel.

[0012] In an embodiment of the present invention, the width of the connecting channel is 50 microns to 1200 microns, and the depth of the connecting channel is 50 microns to 600 microns; the width of the inflow channel is greater than or equal to the width of the connecting channel, and the width of the outflow channel is greater than or equal to the width of the inflow channel.

[0013] In an embodiment of the present invention, the microfluidic chip is further provided with at least one temperature control channel, and the temperature control channel has a temperature control medium fluid inlet and a temperature control medium fluid outlet; the number of the fluid access ports and the number of the fluid access ports are both multiple, and at least one of the fluid access ports is connected to the temperature control medium fluid inlet of at least one of the temperature control channels, and at least one of the fluid access ports is connected to the temperature control medium fluid outlet of at least one of the temperature control channels; wherein, at least one of the temperature control channels is distributed on at least one side of the optical tweezers manipulation and imaging area.

[0014] In an embodiment of the present invention, the chip holder includes a cover plate and a base, the cover plate is connected to the base in a detachable manner, the clamping structure includes two clamping parts, the two clamping parts can clamp and fix the two ends of the microfluidic chip, the cover plate and the base are provided with corresponding chip visual windows, and the chip visual window is located between the two clamping parts; wherein, both the cover plate and the base are provided with installation identification structures around their chip visual windows; the clamping part includes a positioning groove and a positioning boss, the positioning groove is provided on the base, and the positioning boss is provided on the cover plate.

[0015] In an embodiment of the present invention, the fluid access port and the fluid access port are both arranged on the cover plate, the fluid access port is connected to one of the positioning bosses, and the fluid access port is connected to one of the positioning bosses; wherein the fluid access port and the fluid access port and the corresponding positioning bosses are all integrally formed on the cover plate; or the cover plate includes a detachably connected cover plate body and at least one replacement plate, the replacement plate having the positioning boss and the corresponding fluid access port and / or the fluid access port integrally formed thereon; and / or the cover plate body having the positioning boss and the corresponding fluid access port and / or the fluid access port integrally formed thereon.

[0016] In an embodiment of the present invention, the mounting structure includes a plurality of magnetic fixing members, and the plurality of magnetic fixing members are arranged at intervals on the circumferential side surface of the chip holder.

[0017] The present invention also provides an optical tweezers experimental method, which adopts the above-mentioned microfluidic chip device, and the optical tweezers experimental method includes the following steps: installation of the device: the chip clamp fixes the microfluidic chip and correctly fixes the chip clamp to the optical tweezers system through the installation structure; connects one of the fluid access ports to the injection structure of the sample to be tested; connects the fluid access port to the waste liquid discharge structure; obtains the measurement object: opens the injection structure of the sample to be tested, so that the sample to be tested flows into the fluid confluence structure through the corresponding inflow channel, and then makes the sample to be tested enter the optical tweezers manipulation and imaging area and obtains the measurement object; optical tweezers measurement: moves the measurement object to the target area of ​​the optical tweezers manipulation and imaging area for optical tweezers manipulation and mechanical measurement; waste liquid discharge: during the experiment, while opening the inflow channel, the corresponding waste liquid discharge structure is opened to discharge the fluid in the microfluidic chip in time.

[0018] In an embodiment of the present invention, the installation step of the device also includes connecting another fluid access port to the microball injection structure; the acquisition of the measurement object specifically includes the following steps: microball injection: opening the microball injection structure to allow the microball to flow into the fluid confluence structure through the corresponding inflow channel and enter the optical tweezers manipulation and imaging area; microball capture: capturing the microball in the optical tweezers manipulation and imaging area, and then moving the captured microball to the target area of ​​the optical tweezers manipulation and imaging area for mechanical correction; sample injection: opening the injection structure of the sample to be tested to allow the sample to be tested to flow into the fluid confluence structure through the corresponding inflow channel and enter the optical tweezers manipulation and imaging area; establishing connection: moving the microball captured in the target area to the distribution area of ​​the sample to be tested, so that the sample to be tested is connected to the microball; wherein the complex formed by the connection between the sample to be tested and the microball constitutes the measurement object.

[0019] In an embodiment of the present invention, the number of the inflow channels is at least three; the fluid confluence structure includes at least three connecting channels corresponding to the at least three inflow channels and a confluence channel connecting the at least three connecting channels with the outflow channel, and the width of the confluence channel is greater than the width of each inflow channel; the installation step of the device also includes connecting one of the fluid access ports to the injection structure of the buffer solution; the optical tweezers experimental method also includes the following steps: while executing the microsphere injection step, opening the injection structure of the buffer solution, so that the buffer solution enters the confluence channel of the fluid confluence structure in the form of laminar flow through the corresponding inflow channel and the microsphere and enters the optical tweezers manipulation and imaging area; while executing the sample injection step, opening the injection structure of the buffer solution, so that the buffer solution enters the confluence channel of the fluid confluence structure in the form of laminar flow through the corresponding inflow channel and the sample to be tested and enters the optical tweezers manipulation and imaging area; wherein, the distribution layer of the buffer solution in the laminar flow constitutes the target area; the distribution layer of the sample to be tested in the laminar flow constitutes the distribution area of ​​the sample to be tested.

[0020] In an embodiment of the present invention, the outflow channel and the inflow channel are both provided in plurality, the fluid confluence structure comprises a plurality of connection structures, a plurality of connection channels and a confluence channel, the outflow channel is connected to the corresponding inflow channel through the connection structure, and the connection structure is connected to the confluence channel through the corresponding connection channel; in the installation step of the device, the two fluid inlet ports are connected to the two waste liquid discharge structures; the microsphere injection step further comprises: opening the waste liquid discharge structure connected to the corresponding outflow channel, so that the microsphere flows into the corresponding connection structure and / or the connection channel and enters the optical tweezers manipulation and imaging area; the sample injection step further comprises: opening the waste liquid discharge structure connected to the corresponding outflow channel, so that the sample to be tested flows into the corresponding connection structure and / or the connection channel and enters the optical tweezers manipulation and imaging area; wherein the confluence channel of the fluid confluence structure constitutes the target area; the portion of the corresponding connection structure and / or the connection channel into which the sample to be tested flows and located in the optical tweezers manipulation and imaging area constitutes the distribution area of ​​the sample to be tested.

[0021] The characteristics and advantages of the present invention are:

[0022] The microfluidic chip device and optical tweezers experimental method of the present invention utilize a chip holder to clamp and fix the microfluidic chip and install and fix the chip holder on the optical tweezers system, thereby ensuring the positioning accuracy of the microfluidic chip in the optical tweezers system and the stability of the microfluidic chip in the optical tweezers experiment, which is beneficial to improving the capture efficiency and imaging effect in the optical tweezers experiment and improving the repeatability of the measurement results; in addition, the chip holder can realize the disassembly and replacement of different types of microfluidic chips, and the operation is simple.

[0023] The microfluidic chip device of the present invention uses high-transmittance optical glass to make a microfluidic chip, and its overall thickness can be no more than 1.35 mm. It has better optical performance and is not easy to deform. Therefore, it can be applied to an optical tweezers system with a high numerical aperture condenser (such as numerical aperture NA≥1.3) to ensure high-quality optical capture and imaging and minimize optical distortion.

[0024] The microfluidic chip device of the present invention has a connection channel width set to 50 microns to 1200 microns, a fluid channel depth set to 50 microns to 600 microns, and an inflow channel width greater than or equal to the connection channel width, and an outflow channel width greater than or equal to the inflow channel width, thereby enabling optical tweezers experiments on large-sized research objects such as cells, macromolecular polymers or microbial agglomerates with a particle size of 0.5 microns to 20 microns.

[0025] The optical tweezers experimental method of one embodiment of the present invention can achieve independent partitioning of microspheres, buffer solutions and samples to be tested by designing the fluid confluence structure and the number of inflow channels and outflow channels, so that they flow into the confluence channel in the form of laminar flow and enter the optical tweezers manipulation and imaging area, and the above-mentioned introduced substances can be captured, manipulated and mechanically measured in the optical tweezers manipulation and imaging area, thereby effectively avoiding problems such as sample deposition and adhesion and the difficulty in achieving single control due to the complexity of the experimental environment, thereby ensuring the smooth progress of the optical tweezers experiment and the repeatability of the measurement.

[0026] According to another embodiment of the optical tweezers experimental method of the present invention, by designing the fluid confluence structure and the number of inflow channels and outflow channels, the microspheres flow into one connection structure and enter the optical tweezers manipulation and imaging area, and the sample to be tested flows into another connection structure and enters the optical tweezers manipulation and imaging area. First, the optical tweezers system is mechanically corrected using the confluence channel between the two connection channels, and then a connection is established between the sample to be tested and the microspheres through the connection structure at the inflow end of the sample to be tested. Finally, the confluence channel between the two connection channels is used to perform optical tweezers manipulation and mechanical measurement on the complex formed by the sample to be tested and the microspheres. This method can also effectively avoid problems such as sample deposition and adhesion, and the difficulty in achieving single control due to the complexity of the experimental environment, thereby ensuring the smooth progress of the optical tweezers experiment and the repeatability of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 FIG. 4 is a top view of a microfluidic chip device according to an embodiment of the present invention.

[0029] Figure 2 FIG. 4 is a top view of a microfluidic chip device in another embodiment of the present invention.

[0030] Figure 3 FIG. 4 is a top view of the microfluidic chip according to the first embodiment of the present invention.

[0031] Figure 4 FIG. 4 is a top view of a microfluidic chip according to a second embodiment of the present invention.

[0032] Figure 5 The figure is a front oblique view of a cover plate of a chip holder according to an embodiment of the present invention.

[0033] Figure 6 FIG. 4 is a front view of a cover plate of a chip holder according to an embodiment of the present invention.

[0034] Figure 7 The figure is a front oblique view of a base of a chip holder according to an embodiment of the present invention.

[0035] Figure 8 The figure is a rear oblique view of a base of a chip holder according to an embodiment of the present invention.

[0036] Fig. 9 FIG. 1 is a top view of a chip holder according to another embodiment of the present invention clamping the microfluidic chip device according to the first embodiment.

[0037] Fig.10 This is a three-dimensional view of a chip holder according to another embodiment of the present invention clamping the microfluidic chip device according to the first embodiment.

[0038] Fig.11 This is a top view of a chip holder according to another embodiment of the present invention holding the microfluidic chip device according to the second embodiment.

[0039] Fig.12 FIG. 4 is a three-dimensional diagram of a cover plate of a chip holder according to another embodiment of the present invention.

[0040] Fig.13 FIG. 4 is a three-dimensional diagram of a base of a chip holder according to another embodiment of the present invention.

[0041] Fig.14FIG. 4 is a perspective view of a replacement plate according to an embodiment of the present invention.

[0042] Fig.15 A perspective view of a replacement plate according to another embodiment of the present invention.

[0043] In the figure:

[0044] 1. Microfluidic chip;

[0045] 11. Optical tweezers manipulation and imaging area; 12. Imaging area identification structure;

[0046] 100, inflow channel; 101, first inflow channel; 102, second inflow channel; 103, third inflow channel; 104, fluid inlet;

[0047] 110, outflow channel; 111, first outflow channel; 112, second outflow channel; 113, third outflow channel; 114, fluid outlet;

[0048] 120, fluid confluence structure; 121, first connecting channel; 122, second connecting channel; 123, third connecting channel; 124, fourth connecting channel; 125, fifth connecting channel; 126, first confluence channel; 127, second confluence channel; 128, first connecting structure; 129, second connecting structure;

[0049] 130, temperature control channel; 131, temperature control medium fluid inlet; 132, temperature control medium fluid outlet;

[0050] 2. Chip holder;

[0051] 21. Cover plate; 211. Cover plate body; 212. Replacement plate; 214. Fluid access port; 215. Fluid access port; 214'. Fluid access port; 215'. Fluid access port; 216. Upper mounting groove; 217. Mounting port; 218. Second bolt; 219. Second threaded hole; 22. Base; 221. Lower mounting groove; 23. Clamping structure; 231. Clamping portion; 232. Positioning boss; 233. Positioning groove; 24. Mounting structure; 241. Magnetic fixing hole; 25. Chip viewing window; 26. Threaded connection structure; 261. First threaded hole; 262. First bolt; 27. Mounting identification structure. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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. 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.

[0053] Implementation Method 1

[0054] like Figure 1 and Figure 2 As shown, the present invention provides a microfluidic chip device, comprising: a microfluidic chip 1, provided with at least one inflow channel 100 and at least one outflow channel 110, the microfluidic chip 1 has an optical tweezers manipulation and imaging area 11 for optical tweezers manipulation and imaging, the inflow channel 100 is connected with the outflow channel 110 through a fluid confluence structure 120, and the fluid confluence structure 120 is at least partially located in the optical tweezers manipulation and imaging area 11; a chip holder 2, which can be installed and fixed in the optical tweezers system through a mounting structure 24, the chip holder 2 is also provided with a clamping structure 23, at least one fluid access port 214 and at least one fluid access port 215, the microfluidic chip 1 is clamped and fixed by the clamping structure 23, and the inflow channel 100 is connected to the corresponding fluid access port 214, and the at least one fluid access port 215 is connected to the corresponding outflow channel 110.

[0055] The microfluidic chip device of the present invention utilizes a chip holder 2 to clamp and fix the microfluidic chip 1 and installs and fixes the chip holder 2 on the optical tweezers system, thereby ensuring the positioning accuracy of the microfluidic chip 1 in the optical tweezers system and the stability of the microfluidic chip 1 in the optical tweezers experiment, which is beneficial to improving the capture efficiency and imaging effect in the optical tweezers experiment and improving the repeatability of the measurement results; in addition, the chip holder 2 can be used to realize the disassembly and replacement of different types of microfluidic chips 1, and the operation is simple.

[0056] Specifically, Figure 1 and Figure 2 As shown, the inflow channel 100 of the microfluidic chip 1 can be respectively connected to different reagents or samples for optical tweezers experiments. Each fluid access port 214 can be connected to a sampling structure of different reagents or samples, such as a syringe pump, a pressure pump or other injection structure to control the entry of different reagents or samples; the fluid access port 215 is correspondingly connected to a waste liquid collection structure to control the discharge and collection of waste liquid. The number of fluid access ports 214 can be greater than or equal to the number of inflow channels 100. The fluid access ports 214 at the corresponding positions are selectively used according to the positions and numbers of the inflow channels 100 of different microfluidic chips 1, and the redundant fluid access ports 214 are not connected to the sampling structure. Similarly, the number of fluid access ports 215 can be greater than or equal to the number of outflow channels 110. The fluid access ports 215 at the corresponding positions are selectively used according to the positions and numbers of the outflow channels 110 of different microfluidic chips 1, and the redundant fluid access ports 215 are not connected to the waste liquid collection structure. The fluid inlet 214 and the fluid outlet 215 include but are not limited to being connected to the output pipeline connector of the injection structure and the input pipeline connector of the waste liquid collection structure in a threaded connection manner.

[0057] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the material of the microfluidic chip 1 is preferably high-transmittance optical glass; the thickness of the microfluidic chip 1 is preferably less than or equal to 1.35 mm; the microfluidic chip 1 is made of high-transmittance optical glass, so that the thickness of the microfluidic chip 1 can not exceed 1.35 mm, has better optical properties, and is not easy to deform, thereby further improving the optical imaging and optical tweezers capture effects, and can be applied to an optical tweezers system with a high numerical aperture condenser (such as numerical aperture NA ≥ 1.3, especially numerical aperture NA is 1.4) to ensure high-quality optical capture and imaging, and minimize optical distortion.

[0058] Specifically, Figure 3 and Figure 4 As shown, the microfluidic chip 1 includes a chip substrate and a chip cover, the chip cover is covered on the chip substrate, and a channel structure and a corresponding fluid interface are first opened on the chip substrate and / or the chip cover, the fluid interface includes but is not limited to a fluid outlet 114 and a fluid inlet 104, and then the chip substrate and the chip cover are bonded, so that the channel structure forms a circumferentially closed fluid channel. Among them, the chip substrate and the chip cover are made of high-transmittance optical glass.

[0059] In some embodiments of the present invention, at least one groove is provided on the lower surface of the chip cover, and at least one fluid outlet 114 and at least one fluid inlet 104 are provided on the upper surface of the chip cover. The groove connects the fluid outlet 114 and the fluid inlet 104, so that the groove cooperates with the upper surface of the chip substrate to form an outflow channel 110 and an inflow channel 100. The thickness of the chip substrate is about 0.16 mm to 0.18 mm, preferably about 0.17 mm.

[0060] In some other embodiments of the present invention, at least one groove is provided on the upper surface of the chip substrate, at least one fluid outlet 114 and at least one fluid inlet 104 are provided on the chip cover, the groove connects the fluid outlet 114 and the fluid inlet 104, and the groove cooperates with the lower surface of the chip cover to form an outflow channel 110 and an inflow channel 100. The thickness of the chip cover is about 0.16 mm to 0.18 mm, preferably about 0.17 mm.

[0061] In some other embodiments of the present invention, at least one fluid outlet 114 and at least one fluid inlet 104 are provided on the chip cover, and at least one conduit is installed between the chip substrate and the chip cover, the conduit connecting the fluid outlet 114 and the fluid inlet 104, so that an inflow channel 100 and an outflow channel 110 are formed in the conduit.

[0062] In addition, if Figure 3 and Figure 4As shown, the microfluidic chip 1 is provided with an imaging area identification structure 12 in the optical tweezers manipulation and imaging area 11, so that the optical tweezers manipulation and imaging area 11 and the imaging device of the optical tweezers system can be accurately positioned, that is, the imaging area identification structure 12 serves as a reference mark, so that the optical tweezers manipulation and imaging area 11 and the optimal image acquisition area of ​​the imaging device are consistent with or located in the optimal image acquisition area, thereby facilitating the user to perform software control.

[0063] like Figure 1 and Figure 2 As shown, in the embodiment of the present invention, the number of outflow channels 110 and inflow channels 100 is not specifically limited, for example, only one or more can be provided, and they can be used selectively; they can be provided according to the reagents and samples that need to be introduced in the optical tweezers experiment, and different reagents or samples used for the optical tweezers experiment can be introduced separately, including but not limited to microspheres, buffers, culture media, cells, macromolecular polymers or microbial agglomerates, etc. The positions of the outflow channel 110 and the inflow channel 100 are also not specifically limited, that is, if the requirements are met, any fluid interface opened on the microfluidic chip 1 can be selectively used as a fluid inlet 104 so that the channel connected to the fluid interface is selectively used as an inflow channel 100, and any fluid interface can also be selectively used as a fluid outlet 114 so that the channel connected to the fluid interface is selectively used as an outflow channel 110. The specific structure of the fluid confluence structure 120 is provided according to the number and position of the outflow channel 110 and the inflow channel 100. The fluid confluence structure 120 may be entirely located in the optical tweezers manipulation and imaging region 11 , or may be only partially located in the optical tweezers manipulation and imaging region 11 .

[0064] like Figure 1 and Figure 3 As shown, in the first embodiment of the present invention, the number of outflow channels 110 is one, defined as the first outflow channel 111; the number of inflow channels 100 is three, respectively defined as the first inflow channel 101, the second inflow channel 102 and the third inflow channel 103; the fluid confluence structure 120 includes three connecting channels corresponding to the three inflow channels 100 (respectively defined as the first connecting channel 121, the second connecting channel 122 and the third connecting channel 123) and a confluence channel (defined as the first confluence channel 126) connecting the three connecting channels with the outflow channel 110, and the width of the first confluence channel 126 is greater than the width of each inflow channel 100.

[0065] Among them, the first inflow channel 101 is used to introduce microspheres, the third inflow channel 103 is used to introduce buffer solution, and the second inflow channel 102 is used to introduce samples to be tested. During the optical tweezers experiment, in the microsphere capture link, microspheres and buffer solution can be introduced at the same time, and the microspheres flow into the first confluence channel 126 through the first inflow channel 101 and the first connecting channel 121 in turn, and the buffer solution flows into the first confluence channel 126 through the third inflow channel 103 and the third connecting channel 123 in turn, so that the microspheres and the buffer solution meet in the first confluence channel 126 in the form of laminar flow and flow into the first confluence channel 126 located in the optical tweezers manipulation and imaging area 11, and then the user can capture the microspheres in the microsphere distribution layer in the laminar flow in the optical tweezers manipulation and imaging area 11, and move the captured microspheres to the buffer solution distribution layer in the laminar flow, and then perform mechanical correction after stopping the injection of microspheres and buffer solution, such as obtaining relevant information such as optical trap stiffness. Then, the buffer solution and the sample to be tested are introduced at the same time, and the sample to be tested passes through the second inflow channel 102 and the second connecting channel 122 in turn, so that the sample to be tested and the buffer solution meet in the first confluence channel 126 in the form of laminar flow and flow into the first confluence channel 126 located in the optical tweezers manipulation and imaging area 11, and then the user can move the captured microspheres to the distribution layer of the sample to be tested in the laminar flow, and then after stopping the introduction of the sample to be tested and the buffer solution, the microspheres are connected to the sample to be tested, such as the sample to be tested and the microspheres combine to form a complex; after the connection is successful, the complex of the microspheres and the sample to be tested is moved to the buffer solution distribution layer of the laminar flow for optical tweezers manipulation and mechanical measurement. During the experiment, when any inflow channel 100 is opened, the outflow channel 110 needs to be connected to the waste liquid collection structure together so that the waste liquid can be discharged in time.

[0066] By allowing the microspheres and buffer solution as well as the samples to be tested and buffer solution to flow into the confluence channel in the form of laminar flow and enter the optical tweezers manipulation and imaging area 11, a variety of introduced substances can be independently partitioned and manipulated, thereby effectively avoiding problems such as sample deposition, adhesion, and difficulty in achieving single control due to a complex experimental environment, thereby ensuring the smooth progress of the optical tweezers experiment and the repeatability of the measurement.

[0067] Specifically, the depths of the inflow channel 100, the outflow channel 110, the connecting channel and the merging channel are all equal; the width of the first inflow channel 101 is similar to the width of the third inflow channel 103 and both are smaller than the width of the second inflow channel 102; the first connecting channel 121 connects the first inflow channel 101 and the first merging channel 126, and the width of the first connecting channel 121 is smaller than the width of the first inflow channel 101; the third connecting channel 123 connects the third inflow channel 103 and the first merging channel 126, and the width of the third connecting channel 123 is equal to the width of the third inflow channel 103; the second connecting channel 122 connects the second inflow channel 102 and the first merging channel 126, and the width of the second connecting channel 122 is smaller than the width of the second inflow channel 102.

[0068] The connecting channel may be "tapered" or "straight" at a portion of its end; the heights of the left and right sides of the end where the connecting channel is connected to the merging channel may be flush or at different heights. Preferably, the left side of the end of the first connecting channel 121 is lower than the right side of the end, and is connected to the third connecting channel 123 and the first merging channel 126 in a "step-like" shape; the right side of the end of the second connecting channel 122 is lower than the left side, and is connected to the third connecting channel 123 and the first merging channel 126 in a "step-like" shape.

[0069] In a specific embodiment, the third connecting channel 123 is generally located between the two side walls of the first merging channel 126, one side arm of the first connecting channel 121 extends into the first merging channel 126 and is connected to one side arm of the third connecting channel 123, the other side arm of the first connecting channel 121 is connected to one side arm of the first merging channel 126, one side wall of the second connecting channel 122 extends into the first merging channel 126 and is connected to the other side wall of the third connecting channel 123, the other side wall of the second connecting channel 122 is connected to the other side wall of the first merging channel 126 The connection between the first connection channel 121 and the third connection channel 123 and the first confluence channel 126 forms a stepped structure, which is conducive to the microspheres and the buffer solution flowing into the first confluence channel 126 to form a stable laminar structure, and prevent the microspheres from entering other fluid channels; similarly, the connection between the second connection channel 122 and the third connection channel 123 and the first confluence channel 126 also forms a stepped structure, which is conducive to the test sample and the buffer solution flowing into the first confluence channel 126 to form a stable laminar structure, and prevent the test sample from entering other fluid channels. In addition, it is also beneficial to maintain an independent and stable laminar structure between each fluid channel when the three inflow channels 100 (such as the first inflow channel 101, the second inflow channel 102 and the third inflow channel 103) are opened at the same time.

[0070] like Figure 2 and Figure 4As shown, in the second embodiment of the present invention, the number of inflow channels 100 is two, namely the first inflow channel 101 and the second inflow channel 102; the number of outflow channels 110 is two, namely the second outflow channel 112 and the third outflow channel 113; the fluid confluence structure 120 includes two connecting structures (defined as the first connecting structure 128 and the second connecting structure 129, respectively), two connecting channels (defined as the fourth connecting channel 124 and the fifth connecting channel 125, respectively) and a confluence channel (defined as the second confluence channel 127), the connecting structure connects the corresponding outflow channel 110 and the inflow channel 100, and the connecting structure connects the second confluence channel 127 through the corresponding connecting channel, that is, the two ends of the second confluence channel 127 are connected to the fourth connecting channel 124 and the fifth connecting channel 125, respectively, the fourth connecting channel 124 is connected to the first connecting structure 128, and the fifth connecting channel 125 is connected to the second connecting structure 129.

[0071] Among them, the first inflow channel 101 is used to introduce microspheres, and the second inflow channel 102 is used to introduce samples to be tested. During the optical tweezers experiment, in the microsphere capture link, the microspheres are first introduced, and the microspheres flow into the first connection structure 128 through the first inflow channel 101 and enter the optical tweezers manipulation and imaging area 11. The user can capture the microspheres in this area and move the captured microspheres to the second confluence channel 127 through the fourth connection channel 124. Then, after stopping the injection of the microspheres, mechanical correction is performed, such as obtaining relevant information such as optical trap stiffness. Subsequently, the access channel of the sample to be tested is opened, and the sample to be tested flows into the second connection structure 129 through the second inflow channel 102 and enters the optical tweezers manipulation and imaging area 11. The user can move the captured microspheres to the sample distribution area near the second connection structure 129 through the fifth connection channel 125, so that the microspheres are connected to the sample to be tested. After the connection is successful, the complex of the microspheres and the sample to be tested is moved back to the second confluence channel 127 through the fifth connection channel 125 for optical tweezers manipulation and mechanical measurement. During the experiment, the second outflow channel 112 and the third outflow channel 113 are both connected to the waste liquid collection structure so that the waste liquid can be discharged in time.

[0072] The microspheres are allowed to flow into a connection structure and enter the optical tweezers manipulation and imaging area 11, and the sample to be tested flows into another connection structure and enters the optical tweezers manipulation and imaging area 11. The optical tweezers system is first mechanically corrected using the confluence channel between the two connection channels, and then a connection is established between the sample to be tested and the microspheres through the connection structure at the inflow end of the sample to be tested. Finally, the confluence channel between the two connection channels is used to perform optical tweezers manipulation and mechanical measurement on the complex formed by the sample to be tested and the microspheres. This can also effectively avoid problems such as sample deposition and adhesion, and difficulty in achieving single control due to a complex experimental environment, thereby ensuring the smooth progress of the optical tweezers experiment and the repeatability of the measurement.

[0073] Specifically, the depths of the inflow channel 100, the outflow channel 110, the connecting structure, the connecting channel and the converging channel are all equal; the width of the first inflow channel 101 is smaller than the width of the second inflow channel 102; the widths of the fourth connecting channel 124 and the fifth connecting channel 125 are both smaller than the widths of the inflow channel 100 and the outflow channel 110.

[0074] Among them, multiple inflow channels 100 and multiple outflow channels 110 are symmetrically arranged with respect to the fluid confluence structure 120 and correspond one to one. The inflow channels 100 and the outflow channels 110 are connected to form an integral fluid channel, and the positions of the corresponding fluid inlet 104 and fluid outlet 114 can be interchanged, and the positions of the two connecting channels can also be interchanged. The confluence channel has a certain spatial range (such as its width is greater than the width of the connecting channel), and its two ends are connected to the two connecting channels. Its two sides can be open structures (such as its two sides can be connected to other fluid channels or to fluid channels with independent inlets and outlets), or closed structures (such as any geometric shapes such as semi-arcs, rectangles, etc.), so that when mechanical correction, optical tweezers manipulation and mechanical measurement are performed in the second confluence channel 127, the measurement object has a better independent manipulation environment to avoid interference from other introduced substances.

[0075] In a specific embodiment, the upper and lower fluid channels are connected to the corresponding connecting channels through a connecting structure, the portion where the connecting structure connects to the connecting channel is "tapered", and the longitudinal cross-section of the second converging channel 127 is generally circular or elliptical.

[0076] like Figure 1 and Figure 2 As shown, in order to conduct optical tweezer experiments on large-sized research objects such as cells, macromolecular polymers or microbial clumps with a particle size of 0.5 microns to 20 microns, in the embodiment of the present invention, the minimum width of the connecting channel is 50 microns to 1200 microns, preferably 200 microns to 600 microns; the depth of the connecting channel is 50 microns to 600 microns, preferably 100 microns to 500 microns. The width of the inflow channel 100 is greater than or equal to the width of the connecting channel, and the width of the outflow channel 110 is greater than or equal to the width of the inflow channel 100.

[0077] like Figure 3As shown, in some embodiments of the present invention, the microfluidic chip 1 is further provided with at least one temperature control channel 130, and the temperature control channel 130 has two fluid interfaces, which are respectively used as a temperature control medium fluid inlet 131 and a temperature control medium fluid outlet 132; accordingly, at least one fluid access port 214' on the chip holder 2 is connected to the temperature control medium fluid inlet 131 of at least one temperature control channel 130, and at least one fluid access port 215' is connected to the temperature control medium fluid outlet 132 of at least one temperature control channel 130, so as to connect with an external temperature control device to form a temperature control medium circulation loop. The number and distribution position of the temperature control channels 130 are not specifically limited and can be set as needed; for example, at least one temperature control channel 130 can be distributed on at least one side of the optical tweezers manipulation and imaging area 11, so that the optical tweezers manipulation and imaging area 11 can maintain a certain temperature, which is conducive to maintaining a certain physiological state of the sample to be tested; preferably, a temperature control channel 130 is respectively provided on both sides of the optical tweezers manipulation and imaging area 11. Optionally, the two temperature control channels 130 are distributed on both sides of the inflow channel 100. Optionally, the two temperature control channels 130 are distributed on both sides of the outflow channel 110. Optionally, the two temperature control channels 130 are distributed on both sides of the fluid confluence structure 120.

[0078] like Figure 1 and Figure 2 as well as Figures 5 to 8 As shown, in an embodiment of the present invention, the chip holder 2 includes a cover plate 21 and a base 22, the cover plate 21 covers the base 22 and is connected to the base 22 in a detachable manner, the clamping structure 23 includes two clamping parts 231, the two clamping parts 231 can clamp and fix the two ends of the microfluidic chip 1, the cover plate 21 and the base 22 are provided with corresponding chip visual windows 25, and the chip visual window 25 is located between the two clamping parts 231; wherein the clamping part 231 includes a positioning groove 233 and a positioning boss 232, the positioning groove 233 is provided on the base 22, and the positioning boss 232 is provided on the cover plate 21.

[0079] Specifically, the detachable connection between the cover plate 21 and the base 22 includes, but is not limited to, the threaded connection structure 26 in this embodiment, that is, the cover plate 21 and the base 22 are provided with a plurality of corresponding first threaded holes 261, and then the cover plate 21 and the base 22 are connected by passing through a plurality of first bolts 262. The cover plate 21 and the base 22 are both generally frame-shaped plate structures, the positioning boss 232 is provided on the lower surface of the cover plate 21, and the positioning groove 233 is provided on the upper surface of the base 22. The fluid inlet 214 and the fluid outlet 215 are both provided on the cover plate 21, and the fluid inlet 214 is connected to a positioning boss 232, and the fluid outlet 215 is connected to a positioning boss 232, so that after the two ends of the microfluidic chip 1 are clamped and fixed between the two positioning bosses 232 and the two positioning grooves 233, the fluid inlet 104 at one end of the microfluidic chip 1 is connected to the fluid inlet 214, and the fluid outlet 114 at the other end of the microfluidic chip 1 is connected to the fluid outlet 215, and the optical tweezers manipulation and imaging area 11 located in the middle of the microfluidic chip 1 corresponds to the chip visible window 25 of the cover plate 21 and the base 22. In addition, when the temperature control channel 130 is needed, the temperature control channel 130 is connected to the fluid inlet 214' and the fluid outlet 215'. A sealing structure (such as an O-ring, etc.) or a hole boss is provided between the cover plate 21 and the microfluidic chip 1. The sealing structure or hole boss is located at the hole joint between the cover plate 21 and the microfluidic chip 1, such as the joint between the fluid inlet 214 and the fluid inlet 104, the joint between the fluid inlet 215 and the fluid outlet 114, etc., to ensure that a good sealing state can be maintained under pressure conditions.

[0080] In addition, if Figures 5 to 8 As shown, the cover plate 21 and the base 22 are provided with corresponding installation identification structures 27. The orientations of the cover plate 21 and the base 22 can be distinguished according to the installation identification structure 27. On the one hand, the microfluidic chip 1 can be more conveniently positioned and installed in the chip holder 2, and on the other hand, the chip holder 2 can be more conveniently and correctly installed on the workbench of the optical tweezers system.

[0081] like Figure 7 and Figure 8 As shown, in an embodiment of the present invention, the mounting structure 24 includes a plurality of magnetic fixings, and the plurality of magnetic fixings are arranged at intervals on the circumferential side of the chip holder 2. Specifically, a plurality of magnetic fixing holes 241 are arranged at intervals on the circumferential side of the chip holder 2, and the plurality of magnetic fixings are respectively embedded in the plurality of magnetic fixing holes 241. Among them, the magnetic fixings can be magnets. In this embodiment, a plurality of magnetic fixings are mounted on the circumferential side of the base 22. Optionally, a plurality of magnetic fixings are mounted on the circumferential side of the cover plate 21. Optionally, a plurality of magnetic fixings are mounted on the circumferential sides of both the cover plate 21 and the base 22.

[0082] like Figures 5 to 8 As shown, in some embodiments of the present invention, the fluid inlet 214 and the fluid outlet 215 and the corresponding positioning boss 232 are all integrally formed on the cover plate 21. In a specific embodiment, the number of the fluid inlet 214 and the fluid outlet 215 are both three, and the corresponding fluid inlet 214 can be selected to connect to the inflow channel 100, and the fluid outlet 215 can be selected to connect to the outflow channel 110 as needed.

[0083] like Figures 9 to 15 As shown, in some other embodiments of the present invention, the cover plate 21 includes a detachably connected cover plate body 211 and at least one replacement plate 212, and a positioning boss 232 and a corresponding fluid access port 214 and / or fluid access port 215 and / or fluid access port 214' and / or fluid access port 215' are integrally formed on the replacement plate 212. Specifically, an upper mounting groove 216 is provided on the cover plate body 211, and a mounting port 217 is provided on the bottom surface of the upper mounting groove 216. The replacement plate 212 and the cover plate body 211 are provided with a corresponding plurality of second threaded holes 219. The replacement plate 212 can be fixed in the upper mounting groove 216 by a plurality of second bolts 218 inserted into the second threaded holes 219, and the positioning boss 232 passes through the mounting port 217 and matches with the positioning groove 233. In addition, lower mounting grooves 221 can be provided on both sides of the positioning groove 233 to match with the two ends of the replacement plate 212. The base 22 may also be provided with a corresponding plurality of second threaded holes 219 so as to connect the replacement plate 212 with the cover plate body 211 and the base 22 via a plurality of second bolts 218 .

[0084] In some specific embodiments, the cover body 211 is connected to a replacement plate 212 in a detachable manner, and a positioning boss 232 and a corresponding fluid inlet 214 or fluid outlet 215 are integrally formed on the cover body 211, and another positioning boss 232 and a corresponding fluid inlet 214 or fluid outlet 215 are integrally formed on the replacement plate 212.

[0085] like Fig. 9 , Fig.10 as well as Fig.14 As shown, in a specific embodiment, a fluid inlet 215, two fluid inlets 214' and two fluid inlet 215' are provided on the replacement plate 212, the fluid inlet 215 is connected to the first outflow channel 111 of the microfluidic chip 1 in the first embodiment, and the two fluid inlets 214' and the two fluid inlet 215' are connected to the two temperature control channels 130 of the microfluidic chip 1 in the first embodiment.

[0086] like Fig.11 as well as Fig.15As shown, in another specific embodiment, two fluid inlet ports 215 are provided on the replacement plate 212 , and the two fluid inlet ports 215 are correspondingly connected to the second outflow channel 112 and the third outflow channel 113 of the microfluidic chip 1 in the second embodiment.

[0087] In some other specific embodiments, the cover body 211 is detachably connected to the two replacement plates 212 , one replacement plate 212 is integrally formed with a positioning boss 232 and a corresponding fluid inlet 214 , and the other replacement plate 212 is integrally formed with another positioning boss 232 and a corresponding fluid inlet 215 .

[0088] Implementation Method 2

[0089] The present invention also provides an optical tweezers experimental method, which adopts the microfluidic chip device in the first embodiment.

[0090] The optical tweezers experimental method includes the following steps: installation of the device: the chip holder 2 clamps and fixes the microfluidic chip 1 and correctly fixes the chip holder 2 to the optical tweezers system through the mounting structure 24; connects a fluid access port 214 to the sampling structure of the sample to be tested; connects the fluid access port 215 to the waste liquid discharge structure; obtains the measurement object: opens the sampling structure of the sample to be tested, and allows the sample to be tested to flow into the fluid confluence structure 120 through the corresponding inflow channel 100, and then allows the sample to be tested to enter the optical tweezers manipulation and imaging area 11 and obtains the measurement object; optical tweezers measurement: moves the above-mentioned measurement object to the target area for optical tweezers manipulation and mechanical measurement; waste liquid discharge: during the experiment, while opening the inflow channel 100, the corresponding waste liquid discharge structure is opened to discharge the fluid in the microfluidic chip 1 in time.

[0091] In some embodiments of the present invention, the installation step of the device also includes connecting a fluid access port 214 to a microsphere injection structure; obtaining the measurement object specifically includes the following steps: microsphere injection: opening the microsphere injection structure to allow the microsphere to flow into the fluid confluence structure 120 through the corresponding inflow channel 100 and enter the optical tweezers manipulation and imaging area 11; microsphere capture: capturing the microspheres in the optical tweezers manipulation and imaging area 11, and then moving the captured microspheres to the target area of ​​the optical tweezers manipulation and imaging area 11 for mechanical correction; sample injection: opening the injection structure of the sample to be tested, allowing the sample to be tested to flow into the fluid confluence structure 120 through the corresponding inflow channel 100 and enter the optical tweezers manipulation and imaging area 11; establishing connection: moving the microspheres captured in the target area to the distribution area of ​​the sample to be tested, so that the sample to be tested and the microspheres are connected; wherein, the complex formed by the connection between the sample to be tested and the microspheres constitutes the measurement object.

[0092] In a specific embodiment of the present invention, the number of inflow channels 100 is set to at least three and correspondingly connected to at least three fluid access ports 214; the fluid confluence structure 120 includes at least three connecting channels correspondingly connected to the at least three inflow channels 100 and a confluence channel connecting the at least three connecting channels and the outflow channel 110, and the width of the confluence channel is greater than the width of each inflow channel 100; the installation step of the device also includes connecting a fluid access port 214 to the injection structure of the buffer solution; the optical tweezers experimental method also includes the following steps: while executing the microsphere injection step, opening The buffer injection structure is started, so that the buffer enters the confluence channel of the fluid confluence structure 120 in the form of laminar flow through the corresponding inflow channel 100 and the microspheres and enters the optical tweezers manipulation and imaging area 11; while executing the sample injection step, the buffer injection structure is started, so that the buffer enters the confluence channel of the fluid confluence structure 120 in the form of laminar flow through the corresponding inflow channel 100 and the sample to be tested and enters the optical tweezers manipulation and imaging area 11; wherein, the distribution layer of the buffer in the laminar flow constitutes the target area; the distribution layer of the sample to be tested in the laminar flow constitutes the distribution area of ​​the sample to be tested. The above-mentioned steps of simultaneously injecting microspheres and buffer and the steps of simultaneously injecting the sample to be tested and buffer are preferably performed separately, so as to save samples with less content and more precious. Of course, the microspheres, samples and buffer can also be injected at the same time.

[0093] In another specific embodiment of the present invention, the number of outflow channels 110 and inflow channels 100 is set to be multiple and correspondingly connected to multiple fluid access ports 214 and multiple fluid access ports 215, the fluid confluence structure 120 includes multiple connection structures, multiple connection channels and a confluence channel, the connection structure connects the corresponding inflow channel 100 and the outflow channel 110, and the connection structure connects the confluence channel through the corresponding connection channel; in the installation step of the device, the two fluid access ports 215 are connected to the two waste liquid discharge structures; the microsphere injection step also includes: opening the waste liquid discharge structure connected to the corresponding outflow channel 110, so that the microsphere flows into the corresponding connection structure and / or connection channel and enters the optical tweezers manipulation and imaging area 11; the sample injection step also includes: opening the waste liquid discharge structure connected to the corresponding outflow channel 110, so that the sample to be tested flows into the corresponding connection structure and / or connection channel and enters the optical tweezers manipulation and imaging area 11; wherein, the confluence channel of the fluid confluence structure 120 constitutes the target area; the corresponding connection structure and / or connection channel into which the sample to be tested flows, the part located in the optical tweezers manipulation and imaging area constitutes the distribution area of ​​the sample to be tested. The microsphere injection step and the sample injection step are preferably performed separately, so as to save precious samples with less content. Of course, the microsphere injection step and the sample injection step can also be performed simultaneously.

[0094] In some other embodiments of the present invention, in some experiments that do not require the introduction of microspheres, the capture and mechanical measurement of the sample to be tested can be performed in the optical tweezers manipulation and imaging area of ​​any fluid channel, that is, only the sample to be tested is introduced and directly used as the measurement object. For example, in the droplet fusion experiment, it is not necessary to go through all the above operation links, and the appropriate method should be selected according to the specific experimental content.

[0095] The above are only several embodiments of the present invention. Those skilled in the art may make various changes or modifications to the embodiments of the present invention based on the contents disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A microfluidic chip device, characterized in that: include: A microfluidic chip, provided with at least one inflow channel and at least one outflow channel, the microfluidic chip having an optical tweezers manipulation and imaging region, the inflow channel being connected to the outflow channel via a fluid confluence structure, and the fluid confluence structure being at least partially located in the optical tweezers manipulation and imaging region; A chip holder can be fixed in an optical tweezers system through a mounting structure. The chip holder is also provided with a clamping structure, at least one fluid access port and at least one fluid access port. The microfluidic chip is clamped and fixed by the clamping structure, and the inflow channel is connected to the corresponding fluid access port, and the fluid access port is connected to the corresponding outflow channel.

2. The microfluidic chip device according to claim 1, characterized in that: The material of the microfluidic chip is high-transmittance optical glass; the thickness of the microfluidic chip is less than or equal to 1.35 mm.

3. The microfluidic chip device according to claim 1, characterized in that: The microfluidic chip comprises a chip substrate and a chip cover, wherein the chip cover is bonded to the chip substrate; Wherein, at least one groove is provided on the lower surface of the chip cover, and at least one fluid outlet and at least one fluid inlet are provided on the upper surface of the chip cover, and the groove connects the fluid outlet and the fluid inlet, so that the groove cooperates with the upper surface of the chip substrate to form the outflow channel and the inflow channel; and / or The upper surface of the chip substrate is provided with at least one groove, and the chip cover is provided with at least one fluid outlet and at least one fluid inlet. The groove connects the fluid outlet and the fluid inlet, and the groove cooperates with the lower surface of the chip cover to form the outflow channel and the inflow channel.

4. The microfluidic chip device according to claim 1, characterized in that: The number of the inflow channels is at least three; the fluid confluence structure includes at least three connecting channels corresponding to the at least three inflow channels and a confluence channel connecting the at least three connecting channels with the outflow channel, and the width of the confluence channel is greater than the width of each inflow channel.

5. The microfluidic chip device according to claim 1, characterized in that: The outflow channel and the inflow channel are both provided in plurality, and the fluid confluence structure comprises a plurality of connection structures, a plurality of connection channels and a confluence channel, the connection structures connect the corresponding inflow channels and the outflow channels, and the connection structures connect the confluence channels through the corresponding connection channels.

6. The microfluidic chip device according to claim 4 or 5, characterized in that: The width of the connecting channel is 50 microns to 1200 microns, and the depth of the connecting channel is 50 microns to 600 microns; the width of the inflow channel is greater than or equal to the width of the connecting channel, and the width of the outflow channel is greater than or equal to the width of the inflow channel.

7. The microfluidic chip device according to claim 1, characterized in that: The microfluidic chip is also provided with at least one temperature control channel, which has a temperature control medium fluid inlet and a temperature control medium fluid outlet; the number of the fluid access ports and the number of the fluid access ports are both multiple, and at least one of the fluid access ports is connected to the temperature control medium fluid inlet of at least one of the temperature control channels, and at least one of the fluid access ports is connected to the temperature control medium fluid outlet of at least one of the temperature control channels; wherein, at least one of the temperature control channels is distributed on at least one side of the optical tweezers manipulation and imaging area.

8. The microfluidic chip device according to claim 1, characterized in that: The chip holder includes a cover plate and a base, the cover plate is connected to the base in a detachable manner, the clamping structure includes two clamping parts, the two clamping parts can clamp and fix the two ends of the microfluidic chip, the cover plate and the base are provided with corresponding chip viewing windows, and the chip viewing window is located between the two clamping parts; wherein, the cover plate and the base are both provided with installation identification structures around their chip viewing windows; the clamping part includes a positioning groove and a positioning boss, the positioning groove is provided on the base, and the positioning boss is provided on the cover plate.

9. The microfluidic chip device according to claim 8, characterized in that: The fluid inlet and the fluid outlet are both arranged on the cover plate, the fluid inlet is connected to one of the positioning bosses, and the fluid outlet is connected to one of the positioning bosses; Wherein, the fluid inlet, the fluid outlet and the corresponding positioning boss are all integrally formed on the cover plate; or The cover plate includes a detachably connected cover plate body and at least one replacement plate, wherein the replacement plate is integrally formed with the positioning boss and the corresponding fluid access port and / or the fluid access port; and / or the cover plate body is integrally formed with the positioning boss and the corresponding fluid access port and / or the fluid access port.

10. The microfluidic chip device according to claim 1, characterized in that: The mounting structure includes a plurality of magnetic fixing members, and the plurality of magnetic fixing members are arranged at intervals on the circumferential side surface of the chip holder.

11. An optical tweezers experimental method, characterized in that: Using the microfluidic chip device according to any one of claims 1 to 10, the optical tweezers experimental method comprises the following steps: Installation of the device: the chip holder clamps and fixes the microfluidic chip and correctly installs and fixes the chip holder to the optical tweezers system through the mounting structure; connects one of the fluid access ports to the sample injection structure of the sample to be tested; connects the fluid access port to the waste liquid discharge structure; Acquiring a measurement object: opening the sample injection structure of the sample to be measured, allowing the sample to be measured to flow into the fluid confluence structure through the corresponding inflow channel, thereby allowing the sample to be measured to enter the optical tweezers manipulation and imaging area and acquiring a measurement object; Optical tweezers measurement: moving the measurement object to a target area of ​​the optical tweezers manipulation and imaging area to perform optical tweezers manipulation and mechanical measurement; Waste liquid discharge: During the experiment, while the inflow channel is opened, the corresponding waste liquid discharge structure is opened to discharge the fluid in the microfluidic chip in time.

12. The optical tweezers experimental method according to claim 11, characterized in that: The installation step of the device also includes connecting another fluid access port to the microsphere injection structure; The obtaining of the measurement object specifically comprises the following steps: Microsphere injection: opening the microsphere injection structure to allow the microsphere to flow into the fluid confluence structure through the corresponding inflow channel and into the optical tweezers manipulation and imaging area; Microsphere capture: capturing the microsphere in the optical tweezers manipulation and imaging area, and then moving the captured microsphere to a target area of ​​the optical tweezers manipulation and imaging area for mechanical correction; Sample injection: opening the injection structure of the sample to be tested, so that the sample to be tested flows into the fluid confluence structure through the corresponding inflow channel and enters the optical tweezers manipulation and imaging area; Establishing connection: moving the microspheres captured in the target area to the distribution area of ​​the sample to be tested, so that the sample to be tested is connected to the microspheres; wherein the complex formed by the connection between the sample to be tested and the microspheres constitutes the measurement object.

13. The optical tweezers experimental method according to claim 12, characterized in that: The number of the inflow channels is at least three; the fluid confluence structure comprises at least three connecting channels correspondingly connected to the at least three inflow channels and a confluence channel connecting the at least three connecting channels and the outflow channel, and the width of the confluence channel is greater than the width of each of the inflow channels; The installation step of the device also includes connecting one of the fluid access ports to a buffer injection structure; The optical tweezers experimental method also includes the following steps: While performing the microsphere injection step, opening the buffer injection structure, so that the buffer enters the confluence channel of the fluid confluence structure and enters the optical tweezers manipulation and imaging area through the corresponding inflow channel and the microsphere in a laminar flow; While executing the sample injection step, opening the injection structure of the buffer solution, so that the buffer solution and the sample to be tested enter the confluence channel of the fluid confluence structure in the form of laminar flow through the corresponding inflow channel and enter the optical tweezers manipulation and imaging area; Wherein, the distribution layer of the buffer solution in the laminar flow constitutes the target area; and the distribution layer of the sample to be tested in the laminar flow constitutes the distribution area of ​​the sample to be tested.

14. The optical tweezers experimental method according to claim 12, characterized in that: The outflow channel and the inflow channel are both provided in plurality, the fluid confluence structure comprises a plurality of connection structures, a plurality of connection channels and a confluence channel, the outflow channel is connected to the corresponding inflow channel through the connection structure, and the connection structure is connected to the confluence channel through the corresponding connection channel; In the installation step of the device, the two fluid inlet ports are connected to the two waste liquid discharge structures; The microsphere injection step further comprises: opening the waste liquid discharge structure connected to the corresponding outflow channel, so that the microsphere flows into the corresponding connection structure and / or the connection channel and enters the optical tweezers manipulation and imaging area; The sample injection step further includes: opening the waste liquid discharge structure connected to the corresponding outflow channel, so that the sample to be tested flows into the corresponding connection structure and / or the connection channel and enters the optical tweezers manipulation and imaging area; Among them, the confluence channel of the fluid confluence structure constitutes the target area; the portion of the connecting structure and / or the connecting channel into which the sample to be tested flows and located in the optical tweezers manipulation and imaging area constitutes the distribution area of ​​the sample to be tested.

Images