Rapid and Large-Scale\nSynthesis of Chiral and Fluorescent\nSulfur Quantum Dots for Intracellular Temperature Monitoring

The large-scale preparation of fluorescent nanomaterials\nwith laboratory-relevant\nchemical and optical properties will greatly forward their consumer\nmarket applications; however, it still remains challenging. In this\nwork, a universal strategy was developed for the rapid and large-scale\nsynthesis of fluorescent sulfur quantum dots that recently has drawn\ngreat attention because of their unique optical characteristics. From\nthe fact that empty 3d orbitals of sulfide species are able to bind\nwith lone-pair π electrons of the heteroatomic groups, many\namino-group containing compounds, such as amino acid and polyethylenimine\nmolecules, were exploited to synthesize sulfur quantum dots. This\n10 min preparation period endowed sulfur quantum dots with bright\nblue fluorescence and also chirality. Due to the user-friendly and\nrapid operation, this strategy can be extended to the large-scale\nsynthesis of sulfur quantum dots with a yield of 16.844 g for one\nbatch of experiment. Moreover, it was found that the sulfur quantum\ndots exhibited a reversible temperature-dependent luminescent property\nwith a sensitivity of 0.72%/°C, which showed excellent intracellular\ntemperature monitoring capability for inflammation-related disease\ndiagnostics.