Studies On Single Cell Trapping And Long-term Culturing In A Microfluidic Chip

Cells are the most basic structural and functional units that make up living things.Cell research is the foundation for life science,traditionally based on a large number of cells as subjects to obtain statistical results.However,a single cell has a high degree of heterogeneity in terms of its morphology,proliferation,response to external stimuli.As a kind of high pluripotency cell,stem cells can differentiate into cells with different functions.Therefore,it is particularly important for regenerative medicine,especially tissue engineering to study the division and differentiation of stem cells.Single cell capture and isolation is a prerequisite for single cell research.The existing techniques fail to separate and collect individual daughter cells of different generations that divide from the same cell,so there are still limitations in the study of the division and differentiation of single stem cells.Nonetheless,with the increasing maturity of microfluidic technology,it has obvious advantages on precise manipulation,high throughput and easy manipulation of tiny liquids and particles in the field of single cell analysis.In summary,this paper develops a microfluidic chip that combines capture,culture,separation and collection of the single cells with high throughput.The chip utilizes hydrodynamic traps to capture individual cells at corresponding U-shaped sites.The captured cells were cultured in situ for days with time-lapse imaging and media perfusion.One of two daughter cells divided by the original single cell was flushed to the downstream channel and collected in the well plate.In this thesis,numerical simulation and theoretical analysis were used to accurately design the size of the microfluidic chip.The fluid dynamic model of single cell capture and culture was established systematically.Meanwhile,the flow field and pressure in the microfluidic channel were studied.The microcapsules and cells were used to verify the capture efficiency and screening efficiency of the chip to demonstrate its capability in trapping single beads with high throughput and repeatability.Finally,capture and culture of chronic myeloid leukemia cells(K562)were performed to study the,feasibility of the chip in long-term single cell culture..Experiments have shown that the microfluidic chip can achie ve single cell capture,screening and culture,and simultaneously separate different generations of daughter cells from the same single cell.It solves the technical bottleneck in single cell analysis and the study of stem cell division and differentiation,which has a good application prospect in the field of single cell analysis.