A large-scale and rapid digital decomposition chip for liquid phase samples and its application method

Abstract

The invention relates to a large-scale and rapid digital decomposition chip for liquid phase samples and a method for using the chip, which belongs to the field of microfluidic chip analysis technology. The chip consists of a polydimethylsiloxane cover sheet integrated with a microchannel array and The substrate of the microcavity array is formed by reversible bonding. The chip realizes the separation of the micropipe array and the microcavity array, which can not only increase the arrangement density of microcavities per unit area of ​​the chip, increase the number of digital decomposition of liquid samples, but also The tedious digital decomposition operation steps of removing the residual sample liquid in the sampling micropipe based on the gas phase or the oil phase can be avoided, and the time for large-scale digital decomposition of the liquid phase sample is greatly shortened. In addition, the use of this chip does not require precise micropump drive and complex microvalve control, nor does it require complicated macro-micro-interfaces. It can realize large-scale automatic decomposition and uniform distribution of liquid phase samples simply, quickly, and at low cost. Promote the development and widespread application of digital analytics technologies.

Description

technical field [0001] The invention belongs to the technical field of microfluidic chip analysis, and in particular relates to a large-scale and rapid digital decomposition chip for liquid phase samples and a method for using the same. Background technique [0002] High-throughput digital analysis technology has outstanding application advantages in the fields of high-precision nucleic acid quantitative analysis, protein and enzyme activity determination, and single-cell analysis, so it has attracted extensive attention from the biomedical community in recent years. The principle of digital analysis technology is to decompose the sample into a large number of independent micro-units, so that each unit contains 1 or 0 cells or molecules to be analyzed, so that researchers can accurately analyze the samples to be tested at the single-cell or single-molecule level. detection and analysis. For digital analysis technology, the most critical link is the large-scale and uniform d...

AI Technical Summary

Problems solved by technology

This method requires precise and expensive fluidic drive devices to achieve precise control of the flow rates of the two fluid phases, and it also requires the addition of surfactants in the oil or water phase to prevent the fusion of adjacent droplets, which are required to a certain extent. This limits the application of the method

In addition to droplet microfluidic technology, in recent years, some arrayed microfluidic chips have been developed internationally to achieve large-scale decomposition of liquid samples, including microvalve array chips, slip chips, and hydrophilic-hydrophobic graphics chips. , Microcavity array chips with integrated microchannels [Ven K, Vanspauwen B, Pérez-Ruiz E, et al. Target confinement in small reaction volumes using microfluidic technologies: a smart approach for single-entity detection and analysis. ACS sensors, 2018, 3( 2): 264-284.], although these arrayed liquid sample decomposition methods do not need to add surfactants to maintain the stability of the decomposed liquid sample unit, and avoid the impact of adding surfactants on the analysis results, but these methods also have their own Obvious defects, such as the microvalve array chip requires an external air pressure device and complicated macro-micro interface, the slip chip requires cumbersome manual operation and the skilled operation skills of the operator, and the effect of the hydrophilic-hydrophobic graphic chip to decompose the liquid sample is affected. The wettability of the liquid sample to be decomposed and the surface of the chip and the fluid flow rate are greatly affected, and the decomposition effect is unstable, and there are often large differences in the decomposition volume of different liquid samples. It is often necessary to use the oil phase to remove the liquid sample in the sample filling pipeline in order to realize the independence of the liquid sample in each microcavity, but usually the cross-sectional scale of the microchannel is small and the viscosity of the oil phase is large, resulting in a large flow resistance in the microchannel and decomposition. The process takes a long time; in addition, because the micropipes and microcavities are arranged on the same structural layer of the chip in the microcavity array chip with integrated micropipes, the arrangement density of the microcavities per unit area of ​​each chip is limited, thus also The overall decomposition number affecting the final liquid sample

In short, the existing large-scale decomposition methods of microfluidic liquid samples have great limitations in terms of the number of decomposition, the simplicity of operation, the cost of application, and the reliability.

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