Based On Quantum Dots Cytotoxic Cells Chip Platform Is Studied

Quantum dots (QDs) are regarded as promising fluorescent probes for biological applications due to unique size-dependent optical and electronic properties. Compared with traditional organic fluorophores, QDs have a lot of advantages including high fluorescence intensity, broad absorption coefficients, narrow emission spectra, size depending emission and high photostability. With the application and investigation of them, the research of their cytotoxicity becomes more and more important.Microfluidics is a growing technology widely used in biology and chemistry areas. A microfluidic chip can combine lots of steps onto a single device. For life science study, microfluidic cell chips supply a better way for cell-based research or assay. With microfluidic chips, a lot of detail cell analysis have been realized easily.In this study, we demonstrated microfluidic chip as a powerful tool to evaluate the cytotoxicity of QDs, specifically the water-dispersed CdTe, CdTe/CdS and CdTe/CdS/ZnS QDs in HEK293 cells.1. The master of microfluidic chip is fabricated by SU-8-075 photoresist on silicon wafer and the chip is made of PDMS. Microfluidic chips supplied excellent observation, fluorescence detection conditions and high throughput analysis.2. The microfluidic chip is linked to a cell culture equipments (air and heat support) and supplies continuous real-time observation with microscope for a long time.3. We analyzed the cellular morphology and cell survival rate with 3 kinds of QDs in concentration gradient and different application time. CdTe QDs caused cell damage with the concentration over 0.5μM in 24 h and the cytotoxicity of CdTe increased with concentration and effect time. CdTe/CdS show high cytotoxicity after 72 h effect time, while CdTe/CdS/ZnS show little cytotoxicity with high concentration (1μM)and long effect time (72 h).4. The results of cell division rate with QDs are obtained by staining the cells with fluorescent dye. We found that compared to the other two kinds of QDs, CdTe inhibited cell division.5. With Calcein AM and Hochest 33342 double staining, the information about QDs accumulation and distribution in cells is obtained. The information of cell nuclei morphology, cell apoptosis and QDs distribution in cells can be collected all together at the same time by this method.In our study, we evaluated various aspects of the cytotoxicity of QDs in microfluidic chips. Microfluidic chips supplied excellent observation, fluorescence detection conditions and high throughput analysis. The results of our experiment offered novel data for further research of QDs cytotoxicity and toxicity mechanism of QDs.