The Research Of Photodynamic Effect On Human T24 Bladder Cancer Cells Mediated By Graphene Quantum Dots

Objective:To investigate new nano-material-Graphene Quantum Dots(GQDs)mediated photodynamic effect on T24 bladder cancer cells in vitro,and preliminarily discussing its potential functional mechanism.Methods:T24 bladder cancer cells were incubated to logarithmic phase,then different concentrations of GQDs was mixed into the culture medium:(1)after the irradiation of 532-nm laser with different energy density,the growth inhibition rate of T24 cells was monitored by CCK-8 assay and(2)DAPI was used to label the nucleus,the confocal laser scanning microscopy(CLSM)excited by 405nm dual channels was applied to show the subcellular localization of GQDs in T24 cells.Results:①At the concentration of 5ug/ml,the growth inhibition rate of GQDs on T24 cells under laser irradiation of 1J/cm2 and 4J/cm2 was 6.62%and 7.28%,respectively,there was no statistic difference among the two treated groups and the control groups(P>0.05).At concentrations of 10 and 20 g/ml,the growth inhibition rate of GQDs on T24 cells with laser energy of 1J/cm2 was 39.61%and 74.37%,respectively.while under the laser energy of 4J/cm2,the growth inhibition rate of T24 cells was 54.41%and 76.03%,respectively.Compared with the control groups,there were statistical differences(P<0.01).②T24 cells were co-incubated with GQDs.Then with the dual-channel excitation at 405nm,the result of confocal laser scanning microscopy showed that the green fluorescence emitted by GQDs was coincided with the blue fluorescence emitted by DAPI,indicating thatGQDs was located in the nucleus after entering the cell.Conclusions:The new nano-material GQDs mediated photodynamic effect exhibits a clear killing effect on human bladder cancer T24 cells in vitro,with dose and energy dependence.When GQDs enter the cell,they mainly locate at the nucleus and then kill tumor cells.