In vivo toxicity and genotoxicity of L-glutathione capped AgIn5Se8@ZnS nanocrystals

Ternary quantum dots represent a safer alternative for biological applications than conventional binary quantum dots (QDs), which contain harmful elements such as mercury, cadmium, and lead. In this context, AgIn5Se8@ZnS (AISe@ZnS) QDs were synthesized using aqueous electrosynthesis, an approach recognized for its greater eco-efficiency. The glutathione-coated core/shell nanocrystals exhibit continuous absorption from the near-infrared (NIR) at 950 nm to UV, with maximum absorption at 684 nm and a quantum yield of up to 9.6%. The results of the experiments on mice showed that, at concentrations of 5, 10, 50, and 100 mg.kg−1, AISe@ZnS did not induce genotoxicity, as evidenced by the comet and micronucleus tests. These showed similar frequencies of damage and number of micronuclei (MN) to the negative control group (p>0.05). In addition, the acute toxicity tests carried out on mice at these concentrations did not result in deaths, behavioral changes, or significant changes in hematological parameters (erythrocytes, hemoglobin, hematocrit, hemoglobin, and leukocytes) and biochemical parameters (total protein, creatinine, urea, total cholesterol, and triglyceride levels). Histopathological examination of the organs of these animals no showed significant macroscopic or weight changes in the lungs and spleen at the concentrations (5 and 10 mg.kg−1) and no damage to the central nervous system at any concentration tested. Therefore, the AISe@ZnS proved to be less toxic and more sustainable than conventional QDs and organic dyes, emerging as a promising tool for bioimaging applications.