A continuous self-circulation nano-particle preparation microfluidic device and control method

Abstract

The application belongs to the field of inorganic nanomaterials and micro-chemical mechanical technology, and discloses a continuous self-circulation nanoparticle preparation microfluidic device and a control method. A peristaltic pump is connected to the upper end of a precursor container group through a cylindrical microfluidic pipeline with smooth inner wall. A pluggable pipeline joint is connected to the end of the peristaltic pump. The pluggable pipeline joints are connected together through a multi-head mixing joint. An external heating device is connected to a product collection container through a cylindrical microfluidic pipeline with smooth inner wall. A product post-processing device is connected to the upper end of the product collection container through a cylindrical microfluidic pipeline with smooth inner wall. The precursor container or the product collection container, the cylindrical microfluidic pipeline with smooth inner wall and the peristaltic pump can form a self-circulation device, realizing self-circulation function without extending the pipeline, which is conducive to the ripening of nanoparticles. The self-circulation microfluidic device is used for preparing nanoparticles, which is conducive to the batch continuous preparation of high-quality nanoparticles.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of inorganic nanomaterials and micro-chemical mechanical technology, and particularly relates to a continuous self-circulation millifluidic device for preparing nanoparticles and a control method. BACKGROUND

[0002] At present, materials are the basis for human survival and social development. People's survival cannot be separated from materials, and the development of human civilization is often based on the innovation of materials. With the rapid development of modern science and technology, more and more new materials are being developed and widely used, such as nanomaterials. Because when the size of the material is reduced to the length range of 1-100 nm, the performance of the material will usually change, showing unique properties different from bulk materials. Nanomaterials are full name nanoscale structural materials, that is, at least one dimension in three-dimensional space is in the nanometer range (1-100 nm), or materials constructed by them as basic material units.

[0003] With the development of nanotechnology, mass production of high-quality nanomaterials has gradually become the demand for industrialization. For example, in the field of hydrogen fuel cells, nanomaterial catalysts of kilograms need to be coated on the surface of the cell electrode to achieve higher activity and power; in the field of biological medicine, according to the characteristics of the drug, the corresponding nanomaterial carrier is designed to achieve targeted and efficient treatment of diseases. However, the commonly used laboratory preparation method of functionalized nanomaterials (such as hydrothermal method, chemical reduction method, etc.) generally obtains nanomaterials of milligram order and low repeatability, which is not conducive to the popularization and application of nanomaterials.

[0004] In order to solve the problem of batch production of materials, so far a variety of microfluidic-based nanomaterial preparation technologies have been proposed. For example, patent (CN108555309A) proposes a microfluidic preparation technology of size-controllable monodisperse gold nanoparticles, which realizes the accurate and controllable high-throughput preparation of the size, morphology, monodispersity and other characteristics of noble metal nanoparticles. Patent (CN104549585B) proposes a microfluidic chip and a method for preparing nanocapsules using the same, which can realize the loading of different drugs (such as water-soluble drugs and fat-soluble drugs) in the hollow nanoparticles; patent (CN105688772A) proposes a micro-nano material micro-reaction chip to realize the continuous preparation of nanomaterials with uniform morphology and size.

[0005] However, the above method usually faces two problems in practical application, one is that the inner diameter of the microfluidic pipeline is usually 100nm-1mm, and in continuous preparation, especially at the position of pipeline bending, clogging and difficulty in cleaning are prone to occur, thereby affecting the size uniformity of the prepared nanomaterials; the second is that when the prepared nanoparticles need to be aged for a long time to make the particle size more uniform, the pipeline usually needs to be extended to extend the reaction time, which makes the construction of the equipment more complex and is more prone to cause clogging.

[0006] Therefore, based on the external power pump, the application provides a self-circulation microfluidic device (pipeline inner diameter 1-10mm) for preparing nanoparticles, which is helpful for batch continuous preparation of high-quality nanoparticles.

[0007] Through the above analysis, the problems and defects of the prior art are:

[0008] (1) The inner diameter of the microfluidic pipeline is usually 100nm-1mm, and in continuous preparation, especially at the position of pipeline bending, clogging and difficulty in cleaning are prone to occur.

[0009] (2) When the prepared nanoparticles need to be aged for a long time to make the particle size more uniform, the pipeline usually needs to be extended to extend the reaction time, which makes the construction of the equipment more complex. SUMMARY

[0010] In view of the problems of the prior art, the application provides a microfluidic device and control method for continuously and self-circulating preparing nanoparticles.

[0011] The application is implemented as follows, a microfluidic device for continuously and self-circulating preparing nanoparticles comprises:

[0012] a precursor container;

[0013] The precursor container group is connected with a peristaltic pump through a cylindrical microfluidic pipeline with smooth inner wall at the upper end, a pluggable pipeline joint is connected at the end of the peristaltic pump, the pluggable pipeline joints are connected together through a multi-head mixing joint, an external heating device is connected at the rear end of the multi-head mixing joint, the external heating device is connected with a product collection container through a cylindrical microfluidic pipeline with smooth inner wall, and a product post-treatment device is connected with the product collection container through a cylindrical microfluidic pipeline with smooth inner wall at the upper end.

[0014] Further, the precursor container group is provided with two or more precursor containers, a precursor container cover is arranged at the upper end of each precursor container, a microfluidic pipeline interface is arranged at the upper end of the precursor container cover, and an opening is arranged on one side of the microfluidic pipeline interface.

[0015] Further, the microfluidic pipeline interface is circular, the size is the same as the outer diameter of the microfluidic pipeline, and the opening is circular or square.

[0016] Further, the inner wall of the smooth cylindrical microfluidic pipe has a diameter of 1-10 mm and a wall thickness of 0.5-1 mm, and is made of flexible materials such as PE, PP, and PA, and can be bent within an angle of 90-270° without obvious bending.

[0017] Further, the peristaltic pump is a multi-channel peristaltic pump, and the number of internal channels of the multi-channel peristaltic pump is 2-24, and the flow rate of the peristaltic pump is dynamically adjustable at 0.1 mL / min-20 mL / min.

[0018] Further, the two ends of the pluggable pipe are provided with connectors, the connectors are connected with adjacent pluggable pipes through switch buckles, and the pipe can realize liquid transmission without leakage after being connected through the buckles.

[0019] Further, the multi-head mixing connector has 2-10 interfaces, the front end has the same inner diameter r as the inner diameter r of the microfluidic pipe, and can realize the mixing of multiple solutions, and the rear end has an inner diameter R obtained through calculation.

[0020] Further, the calculation formula of the rear end inner diameter R is:

[0021] wherein 2≤n≤10.

[0022] Further, the external heating device is a constant temperature oil bath device or a constant temperature water bath device which can continuously and stably provide heat.

[0023] Further, the product post-treatment device comprises a UV spectrophotometer and a nanoparticle purification instrument.

[0024] Further, the control method of the continuous self-circulation nanoparticle preparation microfluidic device comprises the following steps:

[0025] Step one: 50 mL of 0.1 M cetyltrimethylammonium chloride solution, 12.5 mL of 25 mM chloroauric acid solution, and then 3 mL of 0.1 M sodium borohydride ice water solution are sequentially added to the precursor container A, and then the self-circulation device is started, and the circulation treatment is performed for 2 hours;

[0026] Step two: 200 mL of 0.1 M cetyltrimethylammonium chloride solution and 50 mL of 10 mM chloroauric acid solution are sequentially added to the precursor container B, and then the self-circulation device is started, and the circulation treatment is performed for 2 hours, and the inner diameter of the cylindrical microfluidic pipe is 2 mm, and the flow rate of the peristaltic pump is 5 mL / min.

[0027] Step three: after the reaction, turn off the peristaltic pump, pull out the container A and B from the peristaltic pump and insert them into the detachable pipe joint, use two mixing joints, the inner diameter of the pipe connected to the mixing joint is 2.8mm, and the constant temperature water bath is set to 28℃;

[0028] Step four: turn on the peristaltic pump, the flow rate of the peristaltic pump connected to the precursor container A is 1mL / min, and the flow rate of the peristaltic pump connected to the precursor container A is 3mL / min, so that the gold nanoparticles can be continuously obtained in the product collection container.

[0029] According to the needs, external equipment can be connected to characterize the product in the collection container by ultraviolet spectrum and purify the nanoparticles.

[0030] Another purpose of the application is to provide another control method of the microfluidic device for continuously and self-circulating preparing core-shell structure nanoparticles, and the specific steps are as follows:

[0031] (1) 70mL of 0.1M chloroauric acid aqueous solution is added to the precursor container A, then 10mL of 0.5M sodium borohydride ice water solution is quickly added, and the self-circulation device is turned on, and the circulation treatment is 1 hour;

[0032] (2) At the same time, 20mL of 10mM chloropalladic acid aqueous solution is sequentially added to the precursor container B, then the pipe joint far away from the peristaltic pump is inserted into the detachable pipe joint. The precursor container A device is circulated for 1 hour, the inner diameter of the cylindrical microfluidic pipe is 5mm, and the flow rate of the peristaltic pump is 10mL / min;

[0033] (3) After the reaction of the container A device, the peristaltic pump is turned off, and the container A is pulled out from the pipe joint of the peristaltic pump and inserted into the detachable pipe joint, two mixing joints are used, the inner diameter of the pipe connected to the mixing joint is 7mm, the constant temperature water bath is set to 50℃, and the microfluidic nanoparticle preparation device is assembled according to the legend 1;

[0034] (4) Turn on the peristaltic pump, the flow rate of the peristaltic pump connected to the precursor container A is 2mL / min, and the flow rate of the peristaltic pump connected to the precursor container A is 8mL / min, so that the core-shell structure gold palladium nanoparticles can be continuously obtained in the product collection container.

[0035] Another purpose of the application is to provide another control method of the microfluidic device for continuously and self-circulating preparing core-shell structure nanoparticles, and the specific steps are as follows:

[0036] 1. Add 20 mL of 0.1 M ferric chloride aqueous solution to precursor container A, 20 mL of 0.1 M cobalt chloride aqueous solution to precursor container B, 20 mL of 0.1 M nickel chloride aqueous solution to precursor container C, and 20 mL of 0.5 M ethylene glycol aqueous solution to precursor container D. The inner diameter of the cylindrical millifluidic pipe is 1 mm.

[0037] 2. Pull out the pipe fittings of the four containers away from the peristaltic pump and insert them into the pluggable pipe fittings. Use a 4-head mixing fitting. The inner diameter of the pipe connected after the mixing fitting is 2mm. Set the constant temperature oil bath to 80℃. Assemble the microfluidic nanoparticle preparation device according to Figure 1.

[0038] 3. Turn on the peristaltic pump, and set the flow rate of all pumps to 1.5 mL / min. This will allow for the continuous collection of iron-cobalt-nickel alloy nanoparticles in the product collection container.

[0039] 4. External equipment can be connected as needed to perform ultraviolet spectroscopy characterization and nanoparticle purification of the product in the collection container.

[0040] Based on the above technical solutions and the technical problems solved, please analyze the advantages and positive effects of the technical solution to be protected by this invention from the following aspects:

[0041] First, addressing the technical problems existing in the prior art and the difficulty in solving them, this paper closely analyzes, in conjunction with the technical solution to be protected by this invention and the results and data obtained during the research and development process, how the technical solution of this invention solves the technical problems, and the inventive technical effects brought about by solving these problems. The specific description is as follows:

[0042] This invention, through embodiments comprising a precursor container or product collection container, a smooth-walled cylindrical microfluidic conduit, and a peristaltic pump, forms a self-circulating device, achieving self-circulation without extending the conduit. This benefits the maturation of nanoparticles, improves precursor utilization, and better controls product morphology. Furthermore, it saves unnecessary conduit space, facilitating rapid device assembly. Simultaneously, all conduits are microfluidic conduits (1-10 mm in diameter), which, compared to microfluidic conduits, are less prone to clogging during material preparation and are easier to clean later.

[0043] Second, considering the technical solution as a whole or from a product perspective, the technical effects and advantages of the technical solution to be protected by this invention are specifically described as follows:

[0044] The embodiments of the present invention have a simple structure and obvious effects. The self-circulating millifluidic control device (with an inner diameter of 1-10 mm) is used to prepare nanoparticles, which helps to prepare high-quality nanoparticles in batches and continuously, and realizes the preparation of gram-level nanomaterials.

[0045] Third, as the creation of the invention of the claims of the evidence, but also embodied in the following several important aspects:

[0046] The expected income and commercial value of the technical solution of the present application after transformation are: the present application is conducive to realizing the continuous batch preparation of ordinary nanoparticles, core-shell structure nanoparticles, multi-phase alloy structure nanoparticles and other nanomaterials, reducing human intervention in the preparation process, and improving the success rate of preparation. The nanoparticles prepared by the device can reach the order of magnitude, which can be used for commercial purposes and produce certain commercial value. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 is the structure schematic diagram of the millifluidic device for continuously and self-circulating preparing nanoparticles provided by the embodiment of the present application;

[0048] Figure 2 is the structure schematic diagram of the self-circulating device provided by the embodiment of the present application;

[0049] Figure 3 is the TEM and ultraviolet absorption spectrum characterization diagram of the prepared gold nanoparticles provided by the embodiment of the present application;

[0050] Figure 4 is the element distribution characterization diagram of the core-shell AuPd nanoparticle provided by the embodiment of the present application;

[0051] Figure 5 is the flow chart of the millifluidic device for continuously and self-circulating preparing nanoparticles provided by the embodiment of the present application;

[0052] In the figure: 1, precursor container group; 2, millifluidic pipeline; 3, peristaltic pump; 4, pluggable pipeline joint; 5, multi-head mixing joint; 6, external heating device; 7, product collection container; 8, product post-processing device. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the following will be further described in detail in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0054] I. Explanation of the embodiment. In order to enable those skilled in the art to fully understand how the present application is specifically implemented, this part is an explanation of the embodiment of the technical scheme of the claims.

[0055] As Figure 1As shown, the continuous self-circulation nanoparticle preparation microfluidic device provided by the embodiment of the application comprises a precursor container group 1, a microfluidic pipeline 2, a peristaltic pump 3, a pluggable pipeline joint 4, a multi-head mixing joint 5, an external heating device 6, a product collection container 7, and a product post-processing device 8.

[0056] As shown, when the joints of the pluggable pipeline are all connected to the precursor containers, the self-circulation function of the solution in the precursor containers can be realized. Figure 2

[0057] The upper end of the precursor container group 1 is connected with the peristaltic pump 3 through the inner-wall-smooth cylindrical microfluidic pipeline 2, the peristaltic pump 3 is connected with the pluggable pipeline joint 4 at the end, the pluggable pipeline joint 4 is connected together through the multi-head mixing joint 5, the rear end of the multi-head mixing joint 5 is connected with the external heating device 6, the external heating device 6 is connected with the product collection container 7 through the inner-wall-smooth cylindrical microfluidic pipeline 2, and the upper end of the product collection container 7 is connected with the product post-processing device 8 through the inner-wall-smooth cylindrical microfluidic pipeline 2.

[0058] The precursor container group 1 is provided with two or more precursor containers, and each precursor container is provided with a precursor container cover at the upper end, the upper end of the precursor container cover is provided with a microfluidic pipeline 2 interface, and one side of the microfluidic pipeline 2 interface is provided with an opening.

[0059] The microfluidic pipeline 2 interface is circular, and the size is the same as the outer diameter of the microfluidic pipeline 2, and the opening is circular or square.

[0060] The inner-wall-smooth cylindrical microfluidic pipeline 2 has an inner diameter r of 1-10 mm and a wall thickness of 0.5-1 mm, and is made of flexible materials such as PE polyethylene, PP polypropylene, and PA nylon, which can be bent within an angle of 90-270° without obvious bending.

[0061] The peristaltic pump 3 is a multi-channel peristaltic pump 3, the number of internal channels of the multi-channel peristaltic pump 3 is 2-24, and the flow rate of the peristaltic pump 3 is dynamically adjustable at 0.1 mL / min-20 mL / min.

[0062] The two ends of the pluggable pipeline are provided with joints, the joints are connected with adjacent pluggable pipelines through a switch buckle, and the pipelines can realize liquid transmission without leakage after being connected through the buckle.

[0063] The multi-head mixing joint 5 has 2-10 interfaces, the front end has the same inner diameter r as the inner diameter r of the microfluidic pipeline 2 used, can realize the mixing of multiple solutions, and the rear end has an inner diameter R obtained through calculation.

[0064] The calculation formula of the rear end inner diameter R is:

[0065] Wherein, 2≤n≤10. ​

[0066] The external heating device 6 is a constant temperature oil bath device, a constant temperature water bath device, and a device capable of continuously and stably providing heat.

[0067] The product post-treatment device 8 comprises a UV spectrophotometer, a nanoparticle purification instrument and the like functional devices.

[0068] As shown in the figure, the control method of the microfluidic device for continuously and self-circulating preparing nanoparticles specifically comprises the following steps: Figure 5

[0069] S501: 50 mL of cetyltrimethylammonium chloride solution with a concentration of 0.1 M, 12.5 mL of chloroauric acid solution with a concentration of 25 mM, and then 3 mL of sodium borohydride ice water solution with a concentration of 0.1 M are sequentially added into the precursor container A, and then the self-circulation device is started, and the circulation treatment is performed for 2 hours;

[0070] S502: 200 mL of cetyltrimethylammonium chloride solution with a concentration of 0.1 M and 50 mL of chloroauric acid solution with a concentration of 10 mM are sequentially added into the precursor container B, and then the self-circulation device is started, and the circulation treatment is performed for 2 hours, wherein the inner diameters of the cylindrical microfluidic pipes are all 2 mm, and the flow rates of the peristaltic pumps are all 5 mL / min;

[0071] S503: after the reaction is completed, the peristaltic pump is turned off, the pipe joints of the containers A and B away from the peristaltic pump are pulled out and inserted into the pullable pipe joints respectively, two mixing joints are used, the inner diameter of the pipe connected to the mixing joint is 2.8 mm, and the constant temperature water bath is set to 28 DEG C;

[0072] S504: the peristaltic pump is started, the flow rate of the peristaltic pump connected to the precursor container A is 1 mL / min, the flow rate of the peristaltic pump connected to the precursor container B is 3 mL / min, and thus the gold nanoparticles can be continuously obtained in the product collection container.

[0073] According to the needs, the equipment can be externally connected, and the product in the collection container can be characterized by ultraviolet spectroscopy and purified into nanoparticles.

[0074] Another purpose of the application is to provide another control method of a microfluidic device for continuously and self-circulating preparing core-shell nanoparticles, and the specific steps are as follows:

[0075] (1) 70 mL of chloroauric acid aqueous solution with a concentration of 0.1 M is added into the precursor container A, then 10 mL of sodium borohydride ice water solution with a concentration of 0.5 M is quickly added, and then the self-circulation device is started, and the circulation treatment is performed for 1 hour;

[0076] ​(2) At the same time, 20 mL of 10 mM aqueous chloropalladic acid solution was added into the precursor container B in sequence, and then the pipe joint away from the peristaltic pump was inserted into the pull-out pipe joint. The precursor container A device was circulated for 1 hour, the inner diameter of the cylindrical microfluidic pipe was 5 mm, and the flow rate of the peristaltic pump was 10 mL / min;

[0077] (3) After the reaction of the container A device was completed, the peristaltic pump was turned off, the pipe joint away from the peristaltic pump was pulled out and inserted into the pull-out pipe joint, two mixing joints were used, the inner diameter of the pipe connected to the mixing joint was 7 mm, the constant temperature water bath was set to 50 DEG C, and the microfluidic nanoparticle preparation device was assembled according to the diagram 1.

[0078] (4) The peristaltic pump was turned on, the flow rate of the peristaltic pump connected to the precursor container A was 2 mL / min, the flow rate of the peristaltic pump connected to the precursor container A was 8 mL / min, and the core-shell gold-palladium nanoparticles could be continuously obtained in the product collection container.

[0079] Another purpose of the present application is to provide another control method of a microfluidic device for continuously and self-circulating preparing multiphase alloy nanoparticles, and the specific steps are as follows:

[0080] 1. 20 mL of 0.1 M aqueous ferric chloride solution was added into the precursor container A, 20 mL of 0.1 M aqueous cobalt chloride solution was added into the precursor container B, 20 mL of 0.1 M aqueous nickel chloride solution was added into the precursor container C, and 20 mL of 0.5 M aqueous ethylene glycol solution was added into the precursor container D, and the inner diameter of the cylindrical microfluidic pipe was 1 mm.

[0081] 2. The pipe joints away from the peristaltic pump were pulled out and inserted into the pull-out pipe joint, four mixing joints were used, the inner diameter of the pipe connected to the mixing joint was 2 mm, the constant temperature oil bath was set to 80 DEG C, and the microfluidic nanoparticle preparation device was assembled according to the diagram 1.

[0082] 3. The peristaltic pump was turned on, and the flow rate of all the pumps was 1.5 mL / min, and the iron-cobalt-nickel alloy nanoparticles could be continuously obtained in the product collection container.

[0083] 4. According to the requirements, the equipment was connected, and the product in the collection container was characterized by ultraviolet spectroscopy and nanoparticle purification.

[0084] II. Application Examples. In order to prove the creativity and technical value of the technical scheme of the present application, this part is an application example of the technical scheme of the claim on a specific product or related technology.

[0085] The embodiment of the present application is applied to the continuous and self-circulating preparation of core-shell structure nanoparticles.

[0086] III. Evidence of the effects of the embodiments. The embodiments of the present application have achieved some positive effects in the development or use process, and indeed have great advantages compared with the prior art. The following content is described in combination with the data and graphs of the test process.

[0087] Figure 3 TEM and ultraviolet absorption spectrum characterization figures of the prepared gold nanoparticles provided by the embodiments of the present application. As can be seen from FIG. Figure 3 , the prepared gold nanoparticles have uniform spherical morphology, the size is about 50 nm, and have good monodispersity. As can be seen from FIG. Figure 3 , the prepared gold nanoparticles have an obvious absorption peak at 580 nm, which shows that the prepared gold nanoparticles all have good particle dispersity, which is consistent with the TEM characterization result.

[0088] Figure 4 Element distribution characterization figure of the core-shell AuPd nanoparticles provided by the embodiments of the present application. As can be seen from the figure, the gold element and the palladium element both present spherical distribution with close size, and at the same time, combined with the sparse element point distribution of the palladium element, it shows that the palladium shell is epitaxially conformally grown on the surface of the gold nanoparticles, that is, the successful preparation of the core-shell gold palladium nanoparticles.

[0089] In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0090] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any modification, equivalent replacement and improvement made by any person skilled in the art within the technical range disclosed by the present application, as long as it is within the spirit and principles of the present application, should be covered within the protection scope of the present application.

Claims

1. A control method for a microfluidic device for continuous self-circulating preparation of nanoparticles, characterized in that, The millifluidic device for continuous self-circulation preparation of nanoparticles includes: Precursor container; The upper end of the precursor container assembly is connected to a peristaltic pump via a smooth-walled cylindrical millifluidic pipe. A pluggable pipe connector is connected to the end of the peristaltic pump. The pluggable pipe connectors are connected together via a multi-head mixing connector. The rear end of the multi-head mixing connector is connected to a product collection container via a smooth-walled cylindrical millifluidic pipe. An external heating device is also provided to heat the cylindrical millifluidic pipe. The upper end of the product collection container is connected to a product post-processing device via a smooth-walled cylindrical millifluidic pipe. The precursor container group is provided with two or more precursor containers, including precursor container A and precursor container B. Each precursor container is provided with a precursor container cover at the top end. The precursor container cover is provided with a millifluidic pipe interface at the top end, and an opening is provided on one side of the millifluidic pipe interface. The millifluidic control pipe interface is circular, with the same size as the outer diameter of the millifluidic control pipe, and the opening is circular or square. The specific steps of the control method for the microfluidic device for continuous self-circulation preparation of nanoparticles are as follows: Step 1: Add 50 mL of 0.1 M hexadecyltrimethylammonium chloride solution and 12.5 mL of 25 mM chloroauric acid solution to precursor container A in sequence, then quickly add 3 mL of 0.1 M sodium borohydride ice water solution and start the self-circulation device for 2 hours; connect the pluggable tube connector at the end of the peristaltic pump to precursor container A to form a self-circulation device to realize the self-circulation of the solution in precursor container A; Step 2: Add 200 mL of 0.1 M hexadecyltrimethylammonium chloride solution and 50 mL of 10 mM chloroauric acid solution sequentially to precursor container B, and turn on the self-circulation device to circulate for 2 hours. During this stage, the inner diameter of the cylindrical millifluidic tubing is 2 mm, and the flow rate of the peristaltic pump is 5 mL / min. Connect the pluggable connector of the peristaltic pump end to precursor container B to form a self-circulation device to realize the self-circulation of the solution in precursor container B. Step 3: Connectors are placed at both ends of the pluggable pipe. The connectors are connected to the adjacent pluggable pipes via switch clips. Once the pipes are connected via the clips, liquid can be transferred without leakage. After the reaction is complete, turn off the peristaltic pump. Pull out the pipe connectors of containers A and B that are away from the peristaltic pump and insert them into the pluggable pipe connectors respectively. Use a 2-head mixing connector. The inner diameter of the pipe connected after the mixing connector is 2.8 mm. Set the constant temperature water bath to 28°C. Step 4: Turn on the peristaltic pump. The flow rate of the peristaltic pump connected to precursor container A is 1 mL / min, and the flow rate of the peristaltic pump connected to precursor container A is 3 mL / min. Gold nanoparticles can then be continuously obtained in the product collection container.

2. The control method of the millifluidic device for continuous self-circulation preparation of nanoparticles as described in claim 1, characterized in that, The smooth-walled cylindrical microfluidic pipe is made of flexible materials such as PE polyethylene, PP polypropylene, and PA nylon, which can be bent within an angle of 90-270° without significant bending.

3. The control method of the millifluidic device for continuous self-circulation preparation of nanoparticles as described in claim 1, characterized in that, The peristaltic pump is a multi-channel peristaltic pump with 2-24 internal channels and a flow rate that is dynamically adjustable from 0.1 mL / min to 20 mL / min.

4. The control method of the millifluidic device for continuous self-circulation preparation of nanoparticles as described in claim 1, characterized in that, The external heating device is a constant temperature oil bath device or a constant temperature water bath device that can continuously and stably provide heat.

5. The control method of the millifluidic device for continuous self-circulation preparation of nanoparticles as described in claim 1, characterized in that, The product post-processing device includes an ultraviolet spectrophotometer and a nanoparticle purification instrument.

Images