A microfluidic approach for anticancer drug analysis based on hydrogel encapsulated tumor cells.

A novel method based on fluorescence detection of hydrogel encapsulated cells in microchannels was developed for anticancer drug analysis. In this work, human hepatoma HepG2 cells and human lung epithelial A549 cells were simultaneously immobilized inside two different shapes of three-dimensional hydrogel microstructures using photolithography approach on a same array. Microarrays of living cells offer the potential for parallel detection of many cells and thereby enable high-throughput assays. Using a photolithographic setup, we investigated the prepolymer composition and crosslinking parameters that influenced cell viability inside photocrosslinked hydrogels. The viability of cells encapsulated inside hydrogel microstructures was higher than 90% under optimized photocrosslinking conditions. The cells were further cultured under stable conditions and remained viable for at least three days that were able to carry out cell-based assays. Furthermore, we studied the variation of two intracellular redox parameters (glutathione and reactive oxygen species) in anticancer drug-induced apoptosis in HepG2 and A549 cells. Two anticancer drugs exhibited distinct effects on the levels of intracellular glutathione and reactive oxygen species, indicating the selectivity of these drugs on the disturbance of redox balance within cells. The established platform provides a convenient and fast method for monitoring the effect of anticancer drugs on tumor cells, which is very useful for fundamental biomedical research.