Size dependent cytotoxicity measurements of ZnS quantum dots with multiwavelength fluorescence

ZnS is one of the most promising semiconductor material with a wide band gap and it shows several favorable properties and potential applications in transistors, electroluminescence, sensors, lasers, LEDs, biology and medicine etc. ZnS quantum dots with visible luminescence were synthesized by co-precipitation technique for employment of them in biomedical applications. However, the size of the Q Dots also contributes towards cytotoxicity apart from its material property. Therefore, ZnS Q Dots were synthesized in different particle sizes to investigate the influence of their size on cytotoxicity, using HEK293 cells. Currently other nanosystems like core shell quantum dots with CdS or CdSe as one among the component is being used. However, due to the high level of toxicity of cadmium, a cadmium free alternative will have better potential to be used for bio imaging system. Current investigation shows the potential of ZnS QDs in cellular/bio imaging and hence the assessment of their toxicity becomes essentially important. (author)