Micro-fluidic chip for quickly capturing or detecting cells and method

Abstract

The invention relates to the technical field of biological detection, and discloses a micro-fluidic chip for quickly capturing or detecting cells. The structure of the micro-fluidic chip comprises oneor more groups of micro-fluidic units, wherein the structure of each micro-fluidic unit comprises a channel A and a channel B which are mutually connected; a plurality of groups of herring bone shaped structure units are arranged in each channel A; a microcavity structure is arranged in each channel B; and a DNA tetrahedron is modified in each channel A, and a specific aptamer sequence which canrecognize / capture target cells is connected to the DNA tetrahedron through avidin. According to the micro-fluidic chip disclosed by the invention, the herring bone shaped structure is combined with the cylinder microcavity structure, so that the high-efficient low-cost specific capturing and enriching and in vitro proliferation efficiency of target cells such as food-borne pathogenic bacteria or tumor circulating cells is improved, the captured cells are enriched to the small-volume microcavity structures, and the survival rate of in vitro culturing is further increased.

Description

technical field [0001] The invention relates to the technical field of biological detection, in particular to a microfluidic chip and method for rapidly capturing or detecting cells. Background technique [0002] Foodborne diseases usually refer to diseases caused by ingesting biological, chemical and physical harmful substances that enter the human body with food or drinking water. In recent years, the proportion of foodborne diseases caused by microorganisms in food safety incidents has continued to increase, posing a serious threat to human health and life safety. Enteropathogenic Escherichia coli is a common pathogen that causes diarrhea symptoms in humans. Currently According to different biological characteristics, pathogenic E. coli can be divided into six categories, namely, enteropathogenic E. coli, enterotoxigenic E. coli, enteroinvasive E. coli, enterohemorrhagic E. coli, enteroaggregative E. coli and recently Intestinal Shiga-like toxin-producing and invasive Es...

AI Technical Summary

Problems solved by technology

In the process of detecting food-borne pathogenic microorganisms, the gene chip detection method has the characteristics of small reaction volume, small consumption of reagents, fast detection speed, and high sensitivity, which improves the detection quality and efficiency, but this detection method is expensive and expensive. Low precision; the PCR detection method has achieved a leap from qualitative to quantitative, and high sensitivity can be obtained without subsequent processing during the entire detection process

High-precision detection results, but when it is applied to the detection of food-borne pathogenic bacteria, the ingredients in the food will inhibit the activity of the enzyme in the PCR, which reduces the accuracy of the detection to a certain extent

[0005] (3) Magnetic fluorescence nano-detection method, which combines magnetic nanoparticles and fluorescent nanoparticles with each other in a preset way, so that it takes into account the dual functions of labeling and enrichment, and generates strong fluorescence under the interaction to provide Good magnetic responsiveness, light resistance and light signal, etc., but from the current detection of food-borne pathogenic microorganisms, its application range is limited, and its accuracy, sensitivity and safety cannot be determined

[0007] However, the current research on the capture and activity analysis of circulating tumor cells is facing some problems: 1. CTCs in the peripheral blood of cancer patients are very rare, with as many as 10 million white blood cells and 5 billion red blood cells per milliliter of blood, but only There are several to hundreds of CTCs, and studies have shown that these CTCs have greater heterogeneity, especially functional heterogeneity; 2. The pretreatment and enrichment process in blood samples cause irreversible damage to CTCs, Lead to apoptosis and affect the later biological activity research, thus affecting the evaluation of real-time treatment strategies for patients

The advantage is high sensitivity and specificity, but the disadvantage is that the kit is expensive and cannot be widely used clinically, and the capture efficiency is also limited; in addition, the separation and capture of CTCs based on magnetic particles is as follows: There are also some shortcomings in several aspects: 1. Relying on highly specific tumor-associated antigens, some CTCs will be lost during the capture process; 2. Tumor cells are prone to aggregation in a magnetic field, causing mechanical damage to cells, cell morphology and The activity will also be affected; 3. It is difficult to separate the cells bound to the magnetic beads, which may affect the subsequent detection

Nevertheless, there are still some technical obstacles in many current CTCs sorting technologies based on microfluidic technology: 1. Although the microfluidic chip loaded with capture antibodies has a good ability to capture CTCs, it is difficult to release CTCs after release. There are great difficulties in subsequent analysis; 2. During cell sorting, the biological activity of cells may be damaged due to the shear force in the channel or the collision with the tube wall; 3. This technology is currently mostly used for CTCs Sorting and enrichment, while the research on the in vitro culture of CTCs using microfluidic chip technology is not complete, and there are few integrated research on the capture, release and culture on the chip

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