Research On The Detection Of Calcium Ion In Cell And Cell-Driving Technology Based On Microfluidic Chip

Since microfluidic chip could cut down sample processing time significantly, improve resolution obviously and decline its consume greatly and the cost of experiment will be reduced obviously with its integration and miniaturization, it has been widely used in the fieleds of chemistry, biology, medicine, optics and informatics. Calcium ion in the biologycal cells as the second messenger plays an important role in signal transduction and performs one of major adjustment pivots for cells activities. Some diseases are usually caused by the exceptional concentration of calcium ion in the cell. Through accurate measuring the concentration of calcium ion in the cell, the evidence of correlation between diseases and concentration of calcium ion could be provided, which would be helpful in disease diagnosis, healing and effort judgement after treatment. It would be no doubt meaningful therefore to research on the relationship between concentration of calcium ion and cells function.This thesis, supported by Tianjin Natural Science Foundation Project"The research of microfluidic chip and detection system used in intracellular free calcium", measured the concentration of calcium ion in the cell using a fluorescence ratio method with microfluidic chip, and researched the influence of physical stimulation towards the umbilical vein endothelial cells as well as calcium ion concentration in synovial cells, which would not only pave a foundation to unveil the disease pathogenesis and process, but also be constructive for disease healing. Meanwhile, optical tweezers techniques was also studied, achieved stable trapping of microzyme cell and blood erythrocytes by optical tweezers test rig successfully, and particles could be controled on axial and horizontal directions. It would be a novel approach for the cell drive in the microfluidic chips.Innovative works in the thesis include as follows: Firstly, on the basis of studies of the technology of microfluidic chip, we have designed and manufactured some microfluidic chips for the detection of calcium concentration. meanwhile, we amend the cell load approach because of that the cells could not stop due to pressure balance of the liquids in channels has been affected seriously by the change of outside pressure in traditional methods. Certain concentrated cells were iniected into the entrance pond of chip by removing liquid instrument, and then were drivened into chip channels by the static pressure of liquid caused by the difference of surface between entrance and exit, eventually arrived at inspection area.Secondly, the application of microfluidic chip is studied theoretically. The method of detecting the concentration of calcium ion in the cell using microfluidic chip was presented and the fluorescence-micro-imaging system was builded. By using this system we measured the concentration of calcium ion in synovial cells, as well as the influence of potassium concentration to calcium's. Experimental results proved the feasibility of measuring the concentration of calcium ion in cells quantificationally using the microfluidic chip.Thirdly, the influence of physical stimulation towards calcium concentration in cells was researched by the fluorescence microscopic system. It has been verified by experimental results that either thermal stimulation or shear stress could give some increase of calcium concentration in cells. This conclusion would not only be an inspiration to unveil some diseases mechanism, but also would be guidance for disease healing.Finally, optical tweezers technology was applied on the microfluidic chip in the thesis. On the basis of theoretical analysis and numerical simulation for the technology of optical tweezers, the optical tweezers experimental platform was empoldered. By using it, the microzyme cells and blood erythrocytes had been captured in microfluidic chip,which layed the foundation for the integration of cell driving and measuring in microfluidic chip.