阅读说明：本技术 一种3d微通道的制作方法 (Manufacturing method of 3D micro-channel ) 是由 章安良 于 2019-09-30 设计创作，主要内容包括：本发明公开了一种3D微通道的制作方法,其采用低熔点的焊锡丝构建一个3D微通道模板即微通道图案；利用恒温箱低温固化放置有3D微通道模板的PDMS；对PDMS固化体的顶部进行切除处理以得到3D微通道的两个端口；利用恒温箱高温熔融3D微通道模板,使用注射管和长细软管将熔融的焊锡丝尽量全部挤出；使用注射管使盐酸溶液在3D微通道内反复流动以溶解3D微通道的内壁上剩余的焊锡丝；使用注射管使纯净水在3D微通道内反复流动以清洗器件；优点是其对制作设备要求低,工艺过程简单,且制作得到的3D微通道对微流体的处理能力强。(The invention discloses a method for manufacturing a 3D micro-channel, which adopts a low-melting-point solder wire to construct a 3D micro-channel template, namely a micro-channel pattern; curing PDMS (polydimethylsiloxane) placed with the 3D microchannel template at low temperature by using a constant temperature box; cutting off the top of the PDMS solidified body to obtain two ports of the 3D microchannel; melting the 3D micro-channel template at high temperature by using a thermostat, and extruding the molten solder wires out completely as much as possible by using an injection tube and a long and thin hose; enabling the hydrochloric acid solution to repeatedly flow in the 3D micro-channel by using an injection tube so as to dissolve the residual solder wires on the inner wall of the 3D micro-channel; repeatedly flowing purified water in the 3D microchannel by using an injection tube to clean the device; the method has the advantages of low requirement on manufacturing equipment, simple process and strong microfluid processing capability of the manufactured 3D microchannel.)

1. A manufacturing method of a 3D micro-channel is characterized by comprising the following steps:

the method comprises the following steps: constructing a 3D micro-channel template by using a low-melting-point solder wire;

step two: adding uncured PDMS to a first vessel; then placing the first container containing the uncured PDMS in a thermostat, and curing the PDMS to obtain a PDMS cushion block with the thickness of 1-2 mm; then, after the first container is taken out of the thermostat, the 3D microchannel template is placed in the first container and positioned above the PDMS cushion block, and two ends of the 3D microchannel template are upward; pouring uncured PDMS into the first container to completely submerge the 3D microchannel template into the uncured PDMS; placing the first container which contains the uncured PDMS and is placed in the 3D microchannel template in a thermostat, and curing the PDMS to obtain a PDMS cured body containing the 3D microchannel template;

step three: taking the PDMS solidified body out of the incubator; then, cutting off the top of the PDMS solidified body to obtain two ports of the 3D micro-channel, wherein the position of one port of the 3D micro-channel corresponds to the position of one end of the 3D micro-channel template, and the position of the other port of the 3D micro-channel corresponds to the position of the other end of the 3D micro-channel template;

step four: connecting a long and thin hose to any one port of the 3D microchannel; then placing the PDMS solidified body connected with the long and thin hose into a second container, placing the second container into a thermostat to melt the 3D microchannel template, moving the free end of the long and thin hose out of the thermostat through a slightly opened door of the thermostat, and connecting an injection tube; then repeatedly pushing and pressing the injection tube, and extruding the molten solder wires out through the other port of the 3D micro-channel by using air pressure to obtain the 3D micro-channel;

step five: taking the PDMS solidified body out of the incubator; then placing the PDMS solidified body in a third container containing hydrochloric acid solution; then repeatedly pushing and pulling the injection tube to enable the hydrochloric acid solution to repeatedly flow in the 3D micro-channel so as to dissolve the residual solder wires on the inner wall of the 3D micro-channel; then, the PDMS solidified body is placed in a fourth container filled with purified water; repeatedly pushing and pulling the injection tube to enable the purified water to repeatedly flow in the 3D micro-channel for cleaning;

step six: and connecting a short and thin hose to the other port of the 3D micro-channel, cutting off the part of the long and thin hose to make the length of the long and thin hose consistent with that of the short and thin hose, and respectively using the part of the long and thin hose as a micro-fluid input hose and a micro-fluid output hose to finish the manufacture of the 3D micro-channel.

2. The method as claimed in claim 1, wherein in the first step, the solder wire has a melting point of 138 ℃.

3. The method according to claim 1, wherein in the first step, the 3D microchannel template has a spiral structure.

4. The method according to claim 1, wherein in the second step, the temperature of the incubator is 75-95 ℃ and the holding time is 0.8-1.2 hours.

5. The method according to claim 1, wherein in step four, the length of the long and thin flexible tube is greater than or equal to 50 cm.

6. The method for manufacturing a 3D microchannel according to claim 2, wherein in the fourth step, the temperature of the incubator is 180-220 ℃ and the holding time is 3-5 minutes.

7. The method according to claim 3, wherein in the sixth step, the 3D microchannel is fabricated to have a spiral structure.

Technical Field

The invention relates to a manufacturing technology of a micro-channel in a micro-fluidic chip, in particular to a manufacturing method of a 3D micro-channel.

Background

The development of the micro-electromechanical technology provides a process basis for the micro-fluidic chip, so that a plurality of micro-fluidic operation units can be integrated on one substrate, and conditions are created for the application of the micro-fluidic chip. The micro-fluidic chip can complete biochemical analysis on a substrate with a plurality of square centimeters, and compared with conventional laboratory analysis, the micro-fluidic chip has the advantages of greatly reduced volume, greatly reduced reagents used for analysis, greatly shortened analysis time and easy realization of analysis automation, so that the micro-fluidic chip is developed rapidly since the invention is invented, rapidly permeates into a plurality of fields, influences the life of people and has a great deal of research results on the micro-fluidic chip every year. At present, the microfluidic chip is widely applied to the fields of DNA analysis, cell analysis, protein analysis, drug detection, environmental monitoring, food safety and the like.

The micro-channel is the most basic unit in the micro-fluidic chip, provides a transport channel for micro-fluid in the micro-fluidic chip, provides a basis for a series of operations such as pretreatment, mixing, reaction and the like of reagents and samples in the micro-fluidic analysis process, and is an essential unit of the micro-fluidic chip. Therefore, the great key in the manufacture of the microfluidic chip is the manufacture of a microchannel, and the microfluidic analysis can be completed by combining a proper microchannel with a control and detection unit.

At present, most of the existing microchannels are planar microchannels, and the microchannel manufacturing is realized in a two-dimensional plane by adopting a soft lithography or die casting method. One disadvantage of such microchannels is that the overall size of the microfluidic chip is increased for the manipulation unit to achieve mixing by increasing the length of the microchannel, and the microchannels do not need to be crossed in a plane, which may cause limitations in the overall design of the microchannel. Meanwhile, a typical micro-channel manufacturing method at present often has certain equipment requirements by means of a micro-electro-mechanical system (MEMS) technology, and has certain difficulty in manufacturing a micro-fluidic chip in a common laboratory with limited conditions, so that a new micro-channel manufacturing method is required to overcome the problem of limited design of micro-channels in a two-dimensional plane.

In order to solve the problem of limited crossing in the design and manufacture of micro-channels in a two-dimensional plane, a micro-fluidic chip of a 3D micro-channel is invented by people. Because the paper substrate microfluidic chip is relatively simple to manufacture and relatively low in manufacturing and analysis cost, the 3D paper substrate microfluidic chip is developed. The 3D paper substrate micro-fluidic chip realizes a 3D micro-channel by laminating the paper substrates, so that micro-fluid is transported in the 3D micro-channel, and the paper-based micro-fluidic analysis of the 3D micro-fluidic chip is realized. Although the 3D paper substrate microfluidic chip can realize partial microfluidic analysis, the microfluidic chip has weak microfluidic processing capacity, and microfluidic operations such as sample pretreatment operation, mixing operation, microfluidic flow direction control, enrichment, extraction and the like are difficult to realize on a paper substrate. Therefore, the 3D paper substrate microfluidic chip is suitable for simple microfluidic analysis without complex microfluidic operation, and the application is limited to a certain extent.

The 3D Polydimethylsiloxane (PDMS) micro-channel can overcome the defects of the 3D paper substrate micro-fluidic chip, and can realize various micro-fluidic operations in a 3D space, so that the micro-fluidic chip for laser etching the 3D micro-channel is invented. The 3D micro-channel and other micro-flow units of the PDMS are manufactured by predesigned patterns and controlling the laser etching position. The laser etching method can conveniently realize the 3D micro-channel, but the equipment is expensive and needs to be improved. The 3D printer provides process conditions for the micro-fluidic chip of the 3D micro-channel, and the 3D printer can not only print the micro-fluidic chip of the micro-channel in a two-dimensional plane, but also realize the micro-fluidic chip of the 3D micro-channel. For example, in journal of Electrolysis analysis, 2018, Vol.30, No. 1, No. 101, page 108, 3D-printed microfluidic device based on cottony assay for antioxidant in wine samples, acrylonitrile-butadiene-styrene copolymer and cotton thread printed 3D microchannels are used as reagent microfluidic transport channels, silk-screen printed carbon electrodes are used as electrochemical detectors in the detection zones, and the contents of gallic acid and caffeic acid in the wine samples are detected. The 3D microfluidic device printed by the 3D printer has the advantages that the manufacturing process is simple, various two-dimensional or three-dimensional microchannels and other microfluidic units can be manufactured, but the 3D printer is still expensive and is expensive equipment for a common laboratory, so that the microfluidic chip for manufacturing the 3D microchannel by the 3D printing method is limited by conditions. Therefore, there is a need to develop a simpler, less device demanding method of fabricating 3D microchannels and other microfluidic elements.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a method for manufacturing a 3D micro-channel, which has low requirements on manufacturing equipment and simple process, and the manufactured 3D micro-channel has strong capacity of processing microfluid.

The technical scheme adopted by the invention for solving the technical problems is as follows: a manufacturing method of a 3D micro-channel is characterized by comprising the following steps:

the method comprises the following steps: constructing a 3D micro-channel template by using a low-melting-point solder wire;

step two: adding uncured PDMS to a first vessel; then placing the first container containing the uncured PDMS in a thermostat, and curing the PDMS to obtain a PDMS cushion block with the thickness of 1-2 mm; then, after the first container is taken out of the thermostat, the 3D microchannel template is placed in the first container and positioned above the PDMS cushion block, and two ends of the 3D microchannel template are upward; pouring uncured PDMS into the first container to completely submerge the 3D microchannel template into the uncured PDMS; placing the first container which contains the uncured PDMS and is placed in the 3D microchannel template in a thermostat, and curing the PDMS to obtain a PDMS cured body containing the 3D microchannel template;

step three: taking the PDMS solidified body out of the incubator; then, cutting off the top of the PDMS solidified body to obtain two ports of the 3D micro-channel, wherein the position of one port of the 3D micro-channel corresponds to the position of one end of the 3D micro-channel template, and the position of the other port of the 3D micro-channel corresponds to the position of the other end of the 3D micro-channel template;

step four: connecting a long and thin hose to any one port of the 3D microchannel; then placing the PDMS solidified body connected with the long and thin hose into a second container, placing the second container into a thermostat to melt the 3D microchannel template, moving the free end of the long and thin hose out of the thermostat through a slightly opened door of the thermostat, and connecting an injection tube; then repeatedly pushing and pressing the injection tube, and extruding the molten solder wires out through the other port of the 3D micro-channel by using air pressure to obtain the 3D micro-channel;

step five: taking the PDMS solidified body out of the incubator; then placing the PDMS solidified body in a third container containing hydrochloric acid solution; then repeatedly pushing and pulling the injection tube to enable the hydrochloric acid solution to repeatedly flow in the 3D micro-channel so as to dissolve the residual solder wires on the inner wall of the 3D micro-channel; then, the PDMS solidified body is placed in a fourth container filled with purified water; repeatedly pushing and pulling the injection tube to enable the purified water to repeatedly flow in the 3D micro-channel for cleaning;

step six: and connecting a short and thin hose to the other port of the 3D micro-channel, cutting off the part of the long and thin hose to make the length of the long and thin hose consistent with that of the short and thin hose, and respectively using the part of the long and thin hose as a micro-fluid input hose and a micro-fluid output hose to finish the manufacture of the 3D micro-channel.

In the first step, the melting point of the solder wire is 138 ℃.

In the first step, the 3D micro-channel template is in a spiral structure. Here, the 3D microchannel template is designed to be of a spiral structure, so that the finally manufactured 3D microchannel is also of a spiral structure; 3D micro-channel templates with different shapes can be designed according to needs during specific design so as to obtain 3D micro-channels with different shapes.

In the second step, the temperature of the constant temperature box is 75-95 ℃, and the constant temperature time is 0.8-1.2 hours. When the constant temperature box is used for curing PDMS, the constant temperature can be selected to be relatively low, and the constant temperature time is slightly longer, so that the curing effect of PDMS is better.

In the fourth step, the length of the long and thin hose is more than or equal to 50 cm. Since the free end of the elongated hose needs to be moved out of the incubator to be connected to the injection tube, the length of the elongated hose should be slightly longer.

In the fourth step, the temperature of the constant temperature box is 180-220 ℃, and the constant temperature time is 3-5 minutes. Utilize the thermostated container melting solder wire, because the melting point of solder wire is 138 ℃, consequently need set the constant temperature of thermostated container to be higher than the melting point of solder wire, if constant temperature is higher slightly, then the constant temperature time can be a little short, the purpose is the complete melting solder wire.

And in the sixth step, the manufactured 3D micro-channel is in a spiral structure.

Compared with the prior art, the invention has the advantages that:

1) the 3D microchannel manufactured by the method disclosed by the invention does not need expensive process equipment such as a laser etching instrument and a 3D printer, only needs a common thermostat and an injection tube, and has low requirements on manufacturing equipment; the method for manufacturing the 3D micro-channel does not need a semiconductor process technology to manufacture a mother plate, so that the requirements of process equipment are reduced, the process cost is reduced, and the manufacturing time of a device is reduced; the method for manufacturing the 3D micro-channel does not need a plasma bonding process, so that expensive plasma bonding instrument equipment is not adopted, the bonding process step is omitted, and the manufacturing efficiency of the micro-flow device is improved.

2) According to the method, the microchannel pattern is constructed by using the low-melting-point solder wire, the thermostat is used for curing PDMS (polydimethylsiloxane) placed with the 3D microchannel template at low temperature for the first time, the thermostat is used for melting the 3D microchannel template for the second time, the molten solder wire is extruded by pushing and pressing the injection tube, the residual solder wire on the inner wall of the 3D microchannel is dissolved by using a hydrochloric acid solution by pushing and pulling the injection tube, and finally the pure water is used for cleaning the device by pushing and pulling the injection tube.

3) When the micron-sized 3D microchannel manufactured by the method is used, microfluid is input through the microfluid input hose and reaches the microfluid output hose through the 3D microchannel, so that the transportation of the microfluid can be realized; especially microfluid of different properties, through the input of different microfluid input hoses, through 3D microchannel, realize passive mixing, and then export through microfluid output hose, realize microfluid transport and mix, this kind of 3D microchannel is strong to the throughput of microfluid.

4) The method can be used for manufacturing 3D micro-channels and passive micro-mixers in various shapes, and the mixed fluid is subjected to subsequent micro-flow unit operation to complete micro-flow analysis.

Drawings

FIG. 1 is a schematic view of a 3D microchannel fabricated by the method of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.