CN102817818A - Electrolysis micropump for double-fluid synchronous transmission - Google Patents

Abstract

An electrolytic micropump for synchronous transmission of two fluids, including a pump body, an electrode, a metal tube and a one-way valve; There is a first pumping chamber, an electrolysis chamber is set in the middle piece of the pump body, and a second pumping chamber is set in the lower piece of the pump body; a second pumping chamber is set between the first pumping chamber and the electrolysis chamber. A pump membrane, a second pump membrane is arranged between the second pumping chamber and the electrolysis chamber; the upper piece of the pump body, the first pump membrane, the middle piece of the pump body, the second pump membrane and the lower piece of the pump body Fastened together to form a "sandwich" structure. The invention can transmit two kinds of fluids at the same time. Compared with the single-channel micropump, it can effectively solve the problem of synchronous transmission of two fluids, so that the output flow can be continuously adjusted, completely self-priming, and can work reciprocatingly. At the same time, the present invention can also be manufactured using materials and processes compatible with micro-processing and micro-mechanical technologies, and has the characteristics of small size, light weight, low power consumption, and easy integration.

Description

An electrolytic micropump for synchronous transmission of two fluids

technical field

The invention belongs to the field of micro-electro-mechanical systems, in particular to micro-fluid transmission and control technology, and in particular to the structural design of a novel micro-pump.

Background technique

Microfluidic systems have become a hot area of research in recent years. As an important executive device of microfluidic system, micropump is an important symbol of its development level. Micropumps can be divided into valved micropumps and valveless micropumps according to whether they have a movable valve or not. Valved micropumps are often based on mechanical drive, with simple principles, mature manufacturing processes, and easy control. Miniaturization has greater development prospects.

Micropumps are also significantly used in medical treatment. For example, in the process of certain operations, the operation time is long, the scope is large, and the requirements for block regulation and muscle relaxation are high. At this time, the micropump can be used to slowly infuse anesthetics to make The plane of anesthesia and the effect are accurately controlled to meet the needs of surgical operations, reduce patient discomfort, prevent adverse reactions, and reduce patient pain. Micropumps can also be used as drug delivery devices. For example, micropumps can be used to deliver magnesium sulfate to treat children with asthmatic lung disease, micropumps can be used to treat patients with deep vein thrombosis, and the most widely used is to deliver insulin to treat diabetes.

At present, the conventional methods of tumor treatment include surgery, radiotherapy, chemotherapy, ablation therapy and adjuvant therapy of molecular biology. Surgical treatment has limitations. Radiation therapy and chemotherapy can cause damage to normal tissues while treating tumors. Biological therapy has little trauma to the human body, but it is still in the stage of adjuvant therapy or clinical trials, and has not yet become a mainstream treatment. At present, ablation therapy is the most researched, and the diversity of ablation principles leads to a wide range of devices. Clinically, ablation therapy methods can be roughly divided into thermal ablation methods and chemical ablation methods.

Some of the methods for treating tumors are very complicated to implement, and the equipment requirements are also very high, and the volume of the corresponding equipment is also relatively large. In order to realize the combination with the micropump, the volume of the treatment equipment is required to be small, and the control equipment must also be small. For this consideration, to realize the combination with the micropump, a suitable ablation method is being proposed, which is the thermochemical ablation method. Thermochemical ablation destroys tumor tissue by injecting one or more chemical ablators into the body and utilizing the heat generated by the chemical ablators or their reactions with substances in the body. This method not only retains the protein coagulation effect of chemical ablation agents on tumors, but also achieves the effect of hyperthermia. The combination of the two can achieve higher quality ablation effects, thereby solving the problem of high recurrence rate of chemical ablation. More importantly, the chemical reaction products used are often less toxic, which can eliminate or reduce the toxicity of residual ablation reagents to the body, and realize the concept of "green therapy".

Acid-base neutralization reaction is one of the ablation methods of thermochemical reaction. Taking the reaction of NaOH and HCl as an example, there are two characteristics in the process of chemical reaction NaOH+HCl=NaCl+H ₂ O: ①The heat released by the neutralization reaction is △H=57.32kJ/mol, a small amount of reactants can bring significant heat release; ② After the reaction is completed with an appropriate acid-base solution, the residue is NaCl and water, which are common physiological saline in the human body. The residues have little impact on the human body (whether the intermediate product is toxic needs further evaluation). Therefore, based on the neutralization reaction of local injection of acid-base solution, tumors can be precisely destroyed. This is a highly localized method of thermal ablation compared to conventional hyperthermia measures. Since the injected solution is at normal temperature and releases heat only after entering the target site, it will not cause thermal damage to healthy tissues along the way; at the same time, if the needle used for implant injection is small in diameter (<1 mm), It can effectively avoid the mechanical trauma caused by puncture to the tissue. In this sense, this is a truly minimally invasive tumor hyperthermia method. Moreover, in actual application, the size and location of the tumor can be determined by imaging equipment such as B-ultrasound, CT, and MRI, and an appropriate treatment plan can be designed according to the experimental data, such as determining the chemical reactant, dosage, injection area, etc. The cannula is then surgically inserted into the tumor tissue for injection therapy. It can be seen from this that this method does not require additional expensive equipment, so the cost of surgery and treatment is relatively low.

At present, two single-fluid micropumps are usually used to transmit two fluids in the prior art, which not only increases the cost of the system, but more importantly, it is difficult to ensure the simultaneous transmission of the two solutions.

Contents of the invention

The object of the present invention is to propose an electrolytic micropump for synchronous transmission of two fluids, so as to solve the problem that the micropump for single fluid transmission in the prior art cannot guarantee the synchronous transmission of two fluids.

To achieve the above object, the technical solution of the present invention is as follows: an electrolytic micropump for synchronous transmission of two fluids, characterized in that: the electrolytic micropump contains a pump body, electrodes, metal pipes and a one-way valve; the pump body It is composed of the upper part of the pump body, the middle part of the pump body and the lower part of the pump body. Two pumping chambers; a first pumping membrane is provided between the first pumping chamber and the electrolysis chamber, and a second pumping membrane is provided between the second pumping chamber and the electrolysis chamber; the pump body The upper piece, the first pump membrane, the middle piece of the pump body, the second pump membrane and the lower piece of the pump body are fixed together to form a "sandwich" structure; a catalyst is placed in the electrolysis chamber, and two electrodes are placed in the electrolysis chamber ; At least four metal pipes are used, which are respectively arranged at the inlet and outlet of the first pumping chamber and the second pumping chamber, and each metal pipe is connected to a one-way valve through a hose.

The cross-sectional shapes of the first pumping chamber, the second pumping chamber and the electrolysis chamber in the present invention are all square or circular.

The electrode is integrated with the middle piece of the pump body; the metal tube arranged at the inlet and outlet of the first pumping chamber is integrated with the upper piece of the pump body; the metal tube arranged at the inlet and outlet of the second pumping chamber is integrated with the The lower part of the pump body is combined into one.

The upper piece of the pump body, the first pump membrane, the middle piece of the pump body, the second pump membrane and the lower piece of the pump body are fixed together by bolts and nuts; Round boss.

The present invention has the following advantages and outstanding effects:

1) The present invention can transmit two kinds of fluids at the same time. Compared with single-channel micropumps, it can effectively solve the problem of simultaneous transmission of two fluids, making the output flow continuously adjustable and completely self-priming. It has good synchronization and can work repeatedly.

2) The present invention can be manufactured using materials and processes compatible with micromachining and micromechanical technologies, and has the characteristics of small size, light weight, low power consumption, and easy integration.

Three), the present invention combines with the thermochemotherapy of tumor, has the following advantages:

①Ensuring the synchronous transmission of acid and alkali solutions: choosing the appropriate concentration of acid and alkali solutions can ensure that the acid and alkali solutions are completely reacted, and there will be no surplus, which will cause damage to healthy tissues.

②Simple control: chemical reactants, dosage, implantation area, etc. are all determined in advance. During the treatment, it is only necessary to control the flow of the acid-base solution by controlling the current, and then simply control the heat released by the reaction to treat the disease. The treatment process is controlled.

Description of drawings

FIG. 1 is a schematic diagram of the structure and principle of the embodiment of the dual-fluid micropump provided by the present invention (front sectional view).

Figure 2 is a schematic diagram of the connection of the hose, the metal pipe and the one-way valve.

Fig. 3 is a perspective view of the middle plate of the pump body.

Fig. 4 is a perspective view of the upper piece of the pump body and the lower piece of the pump body.

In the figure: 1-upper pump body; 2-middle pump body; 3-lower pump body; 4-first pumping chamber; 5-electrolysis chamber; 6-second pumping chamber; 7- 1st pump membrane; 8-second pump membrane; 9-electrode; 10-catalyst; 11-metal tube; 12-hose; 13-one-way valve; 14-boss.

Detailed ways

The principle, structure and implementation of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the two-fluid electrolytic micropump provided by the present invention contains a pump body 1, an electrode 9, a metal pipe 11 and a one-way valve 13; The lower part of the pump body is composed of 3, the upper part of the pump body is provided with a first pumping chamber 4, the middle part of the pump body is provided with an electrolysis chamber 5, and the lower part of the pump body is provided with a second pumping chamber. Materials resistant to acid and alkali corrosion can be selected, such as plexiglass, etc.; a first pump membrane 7 is provided between the first pumping chamber and the electrolysis chamber, and a pumping film 7 is provided between the second pumping chamber and the electrolysis chamber. The second pump membrane 8; the upper piece 1 of the pump body, the first pump membrane 7, the middle piece 2 of the pump body, the second pump membrane 8 and the lower piece 3 of the pump body are fixed together to form a "sandwich" structure; the electrolytic chamber The catalyst 10 is placed in the chamber 5, and the two electrodes are placed in the electrolysis chamber; four metal pipes are used, which are respectively arranged at the inlet and outlet of the first pumping chamber and the second pumping chamber, and each metal pipe passes through the The hose 12 is connected with a one-way valve.

Fig. 2 is a schematic diagram of the connection of the hose, the metal pipe and the one-way valve. The flexibility of the hose is used to achieve the sealing of the flow path. Each metal pipe is connected to a one-way valve through the hose 12.

Figure 3 is a three-dimensional view of the middle plate of the pump body. There is a square through hole with rounded corners in the middle, and there is a very small channel on both sides for placing electrodes; there are several through holes around the pump body for placing screws. The upper and lower surfaces of the middle piece of the pump body have a circular boss around the threaded hole. The extrusion of the pump membrane by the boss is stronger than that of other parts of the pump body, so that the pump membrane can be fixed , It will not deform the pump membrane due to the excessive extrusion force of the pump body on the pump membrane, and it can also prevent the fluid from flowing out of the threaded hole.

Figure 4 is a three-dimensional view of the upper piece of the pump body and the lower piece of the pump body. In the middle is a square through-hole groove with rounded corners with a certain depth. The bonding agent combines the metal tube with the upper and lower parts of the pump body; there are several through holes around the pump body for placing screws.

When assembling, first use sealant to bond the middle piece 2 of the pump body with the two electrodes 9, the upper piece 1 of the pump body and the metal pipe 11, and the lower piece 3 of the pump body and the metal pipe. , and then put the hose 12 and the one-way valve 13 on the open end of the metal pipe; fix the middle piece 2 of the pump body, the second pump membrane 8, and the lower piece 3 of the pump body with screws, and inject the prepared solution into the electrolytic In the chamber 5, ensure that there is no leakage; at this time, add the first pump membrane 7 and the upper piece 1 of the pump body, and tighten the screws and nuts at the same time; finally use the sealant to seal the entire micropump. When the rated voltage is applied to the electrolytic micropump, this embodiment can be used as a micropump and can be self-priming; when a DC voltage is applied to the device, it can be used as two microvalves.

In specific use, the hoses at the inlet are respectively inserted into the two fluids, and the outlets of the hoses at the outlet are respectively placed at designated positions, and needles can also be inserted into tissues. Then connect the two electrodes of the micropump to a circuit composed of a power supply, an adjustable resistor, and a switch, and then the electrolytic micropump can be used.

Example:

The manufacturing materials and parts of the dual-fluid micropump in this example are resistant to acid and alkali corrosion. Among them, the manufacturing material of the micropump pump body is 2mm thick plexiglass plate (PMMA), and the manufacturing material of the pump membrane is 0.2 mm thick silica gel film, what the catalyst 10 used was platinum black, the electrode 9 was a platinum electrode wire with a diameter of 0.5 mm, and the check valve 13 was a F2804-40 check valve produced by Delei Fluid Control Engineering Co., Ltd. In addition, the metal tube is a stainless steel tube with an outer diameter of 1 mm, and the hose 12 uses a silicone hose with an outer diameter of 3 mm to connect the micropump and the one-way valve. The whole pump body is packaged with M1.4×8mm screws and M1.4 nuts.

The technical parameters of the embodiment of the present invention: the overall size is 14mmX11mmX6mm (length X width X height), the size of the electrolysis chamber is 8mmX3.8mmX2mm (length X width X height), the size of the pumping chamber is 8mmX3.8mmX1.5mm (length X width x height). 5% Na ₂ SO ₄ solution is used as the electrolyte, and the two fluids are respectively 37.5% HCl solution and 40% NaOH solution.

The electrolysis reaction of this example will produce hydrogen and oxygen, and at the same time redox reactions will take place under the catalysis of platinum. Tested at 3V, the maximum flow rate reached 28μLmin ^-1 . The thermochemical ablation therapy of tumors by using the heat released by the acid-base neutralization reaction has a good application prospect.

Claims (5)

1. An electrolytic micropump for synchronous transmission of two fluids, characterized in that: the electrolytic micropump contains a pump body, an electrode (9), a metal tube (11) and a one-way valve (13); the pump body consists of The upper part of the pump body (1), the middle part of the pump body (2) and the lower part of the pump body (3). The upper part of the pump body (1) is equipped with a first pumping chamber (4), and the middle part of the pump body ( 2) An electrolysis chamber (5) is provided inside, and a second pumping chamber (6) is provided in the lower part of the pump body (3); between the first pumping chamber (4) and the electrolysis chamber (5) There is a first pump membrane (7) between them, and a second pump membrane (8) is arranged between the second pumping chamber (6) and the electrolysis chamber (5); the upper piece of the pump body, the first pump The membrane, the middle piece of the pump body, the second pump membrane and the lower piece of the pump body are fixed together to form a "sandwich" structure; a catalyst (10) is placed in the electrolysis chamber, and two electrodes are placed in the electrolysis chamber (5) ; At least four metal pipes are used, which are respectively arranged at the inlet and outlet of the first pumping chamber (4) and the second pumping chamber (6), and each metal pipe (11) passes through the hose (12) ) is connected with a check valve (13). 2. A kind of electrolytic micropump for two-fluid synchronous transmission as claimed in claim 1, characterized in that: the cross-sectional shapes of the first pumping chamber, the second pumping chamber and the electrolysis chamber are square or round. 3. An electrolytic micropump for synchronous transmission of two fluids according to claim 1, characterized in that: the electrode (9) is integrated with the middle plate (2) of the pump body; it is set in the first pumping The metal tube at the inlet and outlet of the chamber (4) is integrated with the upper piece of the pump body; the metal tube arranged at the inlet and outlet of the second pumping chamber (6) is integrated with the lower piece of the pump body. 4. An electrolytic micropump for synchronous transmission of two fluids according to claim 1, characterized in that: the upper piece of the pump body (1), the first pump membrane (7), the middle piece of the pump body (2 ), the second pump membrane (8) and the lower piece of the pump body (3) are fixed together by bolts and nuts. 5. An electrolytic micropump for dual-fluid synchronous transmission according to claim 5, characterized in that: a circular boss ( 14).

Images