A microfluidic chip for enrichment of Escherichia coli
By designing a microfluidic chip for E. coli enrichment, the problem of low enrichment rate in the prior art is solved, efficient sample removal and E. coli enrichment are achieved, and detection efficiency is improved.
Patent Information
- Application Number
- CN202421374883.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-17
- Publication Date
- 2025-04-01
- Estimated Expiration
- 2034-06-17
AI Technical Summary
Although existing E. coli enrichment methods such as membrane filtration method are low in cost and simple in operation, their enrichment rate is low and it is difficult to meet the needs of efficient detection.
A microfluidic chip is designed, including a PDMS layer and a glass layer. It bonds to the glass layer through mold release to form an enriched liquid flow channel and a waste liquid flow channel, and a filter gap and a dredging structure are set up between the flow channels. The piezoelectric ceramics are used to avoid clogging and achieve efficient enrichment of E. coli.
Through the design of this microfluidic chip, the removal of impurities and efficient enrichment of E. coli are achieved, which improves the enrichment rate and reduces the risk of impurities blockage.
Smart Images
Figure CN222694785U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of microfluidic chips for enriching Escherichia coli, in particular to a microfluidic chip for enriching Escherichia coli. Background Art
[0002] Pathogenic microorganism infection in drinking water is one of the biggest problems endangering people's health, especially in some poor and backward areas. Waterborne infectious diseases are still important diseases that endanger human health, especially to solve the microbial contamination in drinking water. Under normal circumstances, there are mainly Escherichia coli, fecal streptococci and anaerobic bacillus in the intestines. These bacteria can enter the water source with human and animal excrement. Since the number of coliform bacteria in the intestine is large, the number of coliform bacteria in the water source is an important indicator that directly reflects the contamination of the water source by human and animal excrement. Water samples have the characteristics of complex background matrix and low Escherichia coli content, which brings great difficulties to the efficient identification and detection of bacteria. Therefore, the enrichment of bacteria has become a key technology for bacterial detection. The existing Escherichia coli enrichment methods include membrane filtration and magnetic bead enrichment. Compared with the magnetic bead enrichment method, the membrane filtration method has lower cost and simpler operation, but its enrichment rate is lower. For this reason, a microfluidic chip for Escherichia coli enrichment is proposed. Utility Model Content
[0003] The purpose of the utility model is to provide a microfluidic chip for enriching Escherichia coli to solve the problem that the existing Escherichia coli enrichment methods proposed in the above background technology include membrane filtration method and magnetic bead enrichment method. Compared with the magnetic bead enrichment method, the membrane filtration method has lower cost and simpler operation, but its enrichment rate is lower.
[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a microfluidic chip for enriching Escherichia coli, comprising a PDMS layer and a glass layer, wherein the PDMS layer is bonded to the glass layer through demolding to form an enrichment liquid flow channel and a waste liquid flow channel, a sample inlet and a waste liquid outlet are respectively opened at both ends of the waste liquid flow channel, an enrichment liquid outlet is opened at one end of the enrichment liquid flow channel, a filter portion is opened between the enrichment liquid flow channel and the waste liquid flow channel, a dredging structure is opened on the outside of the waste liquid flow channel, and piezoelectric ceramics are glued to the top of the glass layer through epoxy resin.
[0005] Preferably, the filter portion comprises a filter gap, the filter gap is processed between the enriched liquid flow channel and the waste liquid flow channel, and the filter gap connects the enriched liquid flow channel and the waste liquid flow channel.
[0006] Preferably, the dredging structure includes semicircular protrusions, and the outer side of the waste liquid flow channel is evenly processed with multiple semicircular protrusions.
[0007] Preferably, the diameter of the waste liquid flow channel is L1 = 95 μm-105 μm.
[0008] Preferably, the pore size L2 of the filtering gap is 6 μm-10 μm.
[0009] Preferably, the inlet radius size R1 of the sample inlet is 140 μm-160 μm.
[0010] Preferably, the radius size R2 of the semicircular protrusion is 45 μm-55 μm.
[0011] Preferably, the diameter size L3 of the enriched liquid flow channel is 100 μm.
[0012] Compared with the prior art, the utility model adopts the above technical solution and has the following technical effects:
[0013] The utility model provides an enriched liquid outlet, an enriched liquid flow channel, a waste liquid flow channel, a filtering gap and a semicircular protrusion. When in use, the external pipeline is connected with the sample inlet. The filtering gap will filter the impurities, thereby achieving impurity removal. The waste liquid with large particles of impurities will be discharged through the waste liquid outlet, and the enriched liquid containing Escherichia coli will be discharged through the enriched liquid outlet, thereby achieving impurity removal and enrichment of the sample at the same time. When there are many impurities, the piezoelectric ceramic is started to avoid blockage and improve the enrichment rate. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model;
[0016] Figure 2 It is a schematic diagram of the structure of the waste liquid flow channel and the enriched liquid flow channel of the utility model;
[0017] Figure 3 It is a schematic diagram of the size structure of the utility model;
[0018] Figure 4 It is a schematic diagram of the explosion structure of the utility model.
[0019] Explanation of the reference numerals: 1. sample inlet; 2. waste liquid outlet; 3. enriched liquid outlet; 4. enriched liquid flow channel; 5. waste liquid flow channel; 6. filtration gap; 7. semicircular protrusion; 8. piezoelectric ceramic; 9. PDMS layer; 10. glass layer. DETAILED DESCRIPTION
[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0021] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.
[0022] Example
[0023] In the prior art, the existing E. coli enrichment methods include membrane filtration method and magnetic bead enrichment method. Compared with the magnetic bead enrichment method, the membrane filtration method has lower cost and simpler operation, but its enrichment rate is relatively low.
[0024] See also Figure 1-4 The utility model provides a technical solution: a microfluidic chip for enriching Escherichia coli, comprising a PDMS layer 9 and a glass layer 10, wherein the PDMS layer 9 is bonded to the glass layer 10 by demolding to form an enrichment liquid flow channel 4 and a waste liquid flow channel 5, wherein the pipe diameter size L1 of the waste liquid flow channel 5 is 95 μm-105 μm, and a sample inlet 1 and a waste liquid outlet 2 are respectively opened at both ends of the waste liquid flow channel 5, the inlet radius size R1 of the sample inlet 1 is 140 μm-160 μm, and the enrichment liquid flow channel 4 is An enriched liquid outlet 3 is opened at one end, a filtering part is opened between the enriched liquid flow channel 4 and the waste liquid flow channel 5, the tube diameter size L3 of the enriched liquid flow channel 4 is 100μm, a dredging structure is opened on the outside of the waste liquid flow channel 5, and a piezoelectric ceramic 8 is adhered to the top of the glass layer 10 by epoxy resin. When in use, the external pipeline passes through the filtering part to circulate large particles of impurities in the waste liquid flow channel 5, and the enriched liquid containing Escherichia coli flows in the enriched liquid flow channel 4, thereby achieving the removal of impurities and enrichment of the sample at the same time.
[0025] The filter portion includes a filter gap 6, which is processed between the enriched liquid flow channel 4 and the waste liquid flow channel 5, and the filter gap 6 connects the enriched liquid flow channel 4 and the waste liquid flow channel 5. The pore size of the filter gap 6 is L2 = 6μm-10μm. Large particle impurities are separated from the enriched liquid of Escherichia coli through the filter gap 6.
[0026] The dredging structure includes a semicircular protrusion 7. A plurality of semicircular protrusions 7 are evenly processed on the outer side of the waste liquid flow channel 5. The radius size R2 of the semicircular protrusion 7 is 45 μm-55 μm. When there are many impurities, the semicircular protrusion 7 cooperates with the piezoelectric ceramic 8 to cause eddy currents, thereby avoiding accumulation and blockage.
[0027] Working principle or structural principle, when in use, the PDMS layer 9 is demolded and bonded to the glass layer 10 to form an enriched liquid flow channel 4 and a waste liquid flow channel 5, and then the PDMS layer 9 is pasted on the top of the glass layer 10 with epoxy resin, and then the external pipeline is connected to the sample inlet 1. The sample containing Escherichia coli and large particles of impurities reaches the sample inlet 1 through the external pipeline and flows in the waste liquid flow channel 5. During the flow process, the large particles of impurities cannot pass through the filter gap 6 due to their large size, while the smaller Escherichia coli can pass through the filter gap 6, thereby achieving impurity removal. When the liquid flows to the ends of the waste liquid flow channel 5 and the enriched liquid flow channel 4, the waste liquid containing large particles of impurities will be discharged through the waste liquid outlet 2, while the enriched liquid containing Escherichia coli will be discharged through the enriched liquid outlet 3, thereby achieving both impurity removal and enrichment of the sample. When there are many impurities, the piezoelectric ceramic 8 is started. The piezoelectric ceramic 8 generates sound waves, and the vibration caused by the semicircular protrusion 7 can cause eddy currents in the enriched liquid flow channel 4 and the waste liquid flow channel 5, thereby taking away impurities blocked in the filter gap 6, avoiding blockage, and improving the enrichment rate.
[0028] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways, even if such combinations and / or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All of these combinations and / or combinations fall within the scope of the present invention.
Claims
1. A microfluidic chip for enriching Escherichia coli, comprising a PDMS layer (9) and a glass layer (10), characterized in that: The PDMS layer (9) is bonded to the glass layer (10) by demoulding to form an enriched liquid flow channel (4) and a waste liquid flow channel (5); the two ends of the waste liquid flow channel (5) are respectively provided with a sample inlet (1) and a waste liquid outlet (2); one end of the enriched liquid flow channel (4) is provided with an enriched liquid outlet (3); a filter portion is provided between the enriched liquid flow channel (4) and the waste liquid flow channel (5); a dredging structure is provided on the outside of the waste liquid flow channel (5); and a piezoelectric ceramic (8) is bonded to the top of the glass layer (10) by epoxy resin.
2. A microfluidic chip for enriching Escherichia coli according to claim 1, characterized in that: The filter portion comprises a filter gap (6), wherein the filter gap (6) is machined between the enriched liquid flow channel (4) and the waste liquid flow channel (5), and the filter gap (6) connects the enriched liquid flow channel (4) and the waste liquid flow channel (5).
3. A microfluidic chip for enriching Escherichia coli according to claim 1, characterized in that: The dredging structure comprises a semicircular protrusion (7), and a plurality of semicircular protrusions (7) are evenly processed on the outer side of the waste liquid flow channel (5).
4. A microfluidic chip for enriching Escherichia coli according to claim 1, characterized in that: The pipe diameter size L1 of the waste liquid flow channel (5) is 95 μm-105 μm.
5. A microfluidic chip for enriching Escherichia coli according to claim 2, characterized in that: The pore size of the filtering gap (6) is L2 = 6 μm-10 μm.
6. A microfluidic chip for enriching Escherichia coli according to claim 1, characterized in that: The inlet radius size R1 of the sample inlet (1) is 140 μm-160 μm.
7. A microfluidic chip for enriching Escherichia coli according to claim 3, characterized in that: The radius size R2 of the semicircular protrusion (7) is 45 μm-55 μm.
8. The microfluidic chip for enriching Escherichia coli according to claim 1, characterized in that: The diameter size L3 of the enriched liquid flow channel (4) is 100 μm.