Construction And Application Of Microfluidic Chip--ICP-MS Single Cell Analysis Platform

Individual differentiation information in a cell population can be obtained from single cell analysis,which has become one of the important research directions in the field of life analysis in recent years.The analytical method based on inductively coupled plasma mass spectrometry(ICP-MS)provides a powerful tool for single-cell element analysis,and has great application potential in life sciences,pharmacy and environmental science research.This paper intends to combine the miniaturized,easy-to-automate,and highly portable microfluidic chip with the highly sensitive element-specific detector ICP-MS to establish a fast,highly sensitive,and high-throughput Chip-ICP-MS single cell element analysis platform.On this basis,this method is used to explore the uptake behavior and mechanism of different heavy metals by Chlamydomonas reinhardtii at the single-cell level.The specific research contents are as follows:(1)A serpentine microchannel microfluidic chip with periodic confined micropillars was designed and fabricated,using inertial migration and Dean secondary flow to promote a single-cell stream of Chlamydomonas reinhardtii with a density of 2×10~6 cells/m L.The chip has the advantages of reliable and efficient focusing performance,simple structure,compact layout,and strong compatibility.(2)The prepared microfluidic chip was combined with ICP-MS to realize the online combination,and the detection parameters were optimized to realize the detection of mercury in a single Chlamydomonas cell.The analysis platform has the advantages of stable single-cell focusing effect,simple preparation,low cost,high throughput and reliable results.It is a powerful tool for single-cell element analysis.(3)The constructed chip-ICP-MS single-cell analysis platform was used to study the uptake behavior of Chlamydomonas cells to Hg(?),Cd(?)and As(?).The results showed that the uptake of cells presented a trend of Hg(?)>Cd(?)>As(?),and there was obvious heterogeneity between individual cells.The cell wall of Chlamydomonas cells had more adsorption of Cd(?),while the main absorption of As(?)and Hg(?)was intracellular.