Cholera-diagnosing apparatus with recyclable and easily-dismantlable driving members

Abstract

The invention relates to a cholera-diagnosing apparatus with recyclable and easily-dismantlable driving members, belonging to the field of analytical testing. A series of obstacles exist in preparation of a substrate for a cholera-diagnosing micro-fluidic chip from cheap and easily workable polydimethylsiloxane (PDMS). According to main points of a technical scheme in the invention, PDMS with an original surface is selected as a substrate; an elastic clamp, additionally provided with a minisized ultrasonic transducer on its clamping arm, is positioned at a position where the sample liquid flowterminal of a micro-fluidic chip is located in the manner of elastic occlusion, and ultrasonic waves are used for inducing formation of a driving force based on the difference between interfacial tension forces; meanwhile, the driving force is coupled and coordinated with the driving force of a micropump to drive sample liquid flow to flow toward the terminal; and the pipelines of the chip are filled with a micronsized silica particle filler which is used for supporting the inner walls of the pipelines, compensating original hydrophobic pipelines with a set of hydrophilic micro-channels, andextruding and covering the inner wall surfaces of the pipelines so as to reduce the contact between biological macromolecules and the inner wall surfaces.

Description

Technical field [0001] The invention relates to a device for diagnosing cholera that is easy to disassemble and recyclable for driving components. The device is a special device for diagnosing cholera antigen based on antigen / antibody specific reaction, and belongs to the field of analysis and testing. Background technique [0002] For the technical background of multi-channel microfluidic cholera diagnosis, please refer to CN 200910150930.4 and other invention patent applications. [0003] For the overall overview of microfluidic technology itself, you can refer to the monograph "Illustrated Microfluidic Chip Lab" recently published by the famous microfluidic expert Mr. Lin Bingcheng. This monograph has been published by Science Press. The past, present, and future prospects of microfluidic technology are all detailed and detailed long discussions. [0004] So, let's talk about the key issues of concern in this case. [0005] The basic structure of a microfluidic chip includes a sub...

AI Technical Summary

Problems solved by technology

[0007] But it's not that simple

[0008] First, this polydimethylsiloxane material, which is referred to by the acronym PDMS, is itself a strongly hydrophobic material, and channels are built on this material. modification operation, then, after the overall assembly is completed, that is, after the cover is covered, because the inner surface of the channel in the structure occupies most of the inner surface of the liquid flow channel, then the inner surface of the PDMS channel is The strong hydrophobicity is the decisive factor, it will make it very difficult for the polar liquid fine flow similar to the aqueous solution to pass through, and its flow resistance is so large that even the general micropump is difficult to push, of course, if the cover sheet is also If you choose to use the PDMS material, then the problems are basically the same, with minor differences; therefore, in the prior art, it is necessary to modify and modify the inner surface of the channel on the PDMS material; then, this is for the PDMS channel Is the modification operation of the inner surface of the channel very troublesome? That's not the problem. What constitutes a serious technical problem is another problem: the PDMS polymer molecules in the bulk phase of the PDMS material substrate have the characteristics of automatic diffusion and migration to the surface. The characteristics of polymer molecules diffusing and migrating to the surface automatically will make the modified state of the inner surface of the channel modified by the surface unable to maintain for a long enough time. The maintenance time of the internal surface state is roughly only enough to complete the time required for the internal test experiment in the laboratory; in other words, the surface state of the PDMS channel inner surface after surface modification or surface modification is formed after modification It cannot last for a long time, but it will automatically tend to or change back to the surface state before the surface modification, and return to the original strongly hydrophobic surface state in a short period of time. Then, just imagine, such a slight Can flow control chips be produced in large quantities, stored in large quantities, and widely promoted? The answer is obvious, that is, impossible

[0017] Third, as mentioned above, the inner surface of the PDMS channel is strongly hydrophobic, and targeted surface chemical modification or surface chemical modification is difficult to last. It is effective to use it within a short period of time; if the relatively short expiration date has passed and it is still used forcibly, since the surface state is already close to the hydrophobic state, there must be a relatively large liquid flow driven by the conventional micropump. In this way, the sample liquid can only be forced to flow in the target direction by increasing the pumping power and pumping pressure of the micropump. Sending pressure to pump the sample liquid flow will cause bubbling, puffing, twisting, and deformation of the channel at the sampling end of the substrate, including the area near the sampling end, and, under such high pressure conditions, in the The channel and its periphery at the injection end and its vicinity are also prone to peeling between the substrate and the cover slip. In this case, the sample solution will enter the gap between the substrate and the cover slip formed after the peeling. This actually leads to the damage of the microfluidic chip; of course, if the surface modification or surface modification is not in place, it will also lead to the above-mentioned situation within the short customary validity period; In the case of an external micropump for liquid flow drive, the above-mentioned problem always exists

As mentioned above, if no pre-operations such as surface modification or surface modification have been done at all, then the above-mentioned problem will be more serious, even if there is no channel bubbling at the injection end and its vicinity, Problems such as puffing, twisting, deformation, and peeling between the substrate and the cover sheet, etc., just because the flow resistance is too large, the use of a high-pressure micropump may not be able to drive the sample liquid flow toward the terminal.

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