BSA-assisted ultrasound synthesis of water stable CsPbBr₃ nanocrystals for sensitive fluorescent detection of hydrogen sulfide in human serum

A bovine serum albumin (BSA)-assisted ultrasonication strategy was developed for the synthesis of CsPbBr3 nanocrystals (NCs) with stable fluorescence properties in aqueous solution. Such a preparation method is simple, fast and does not require complex equipment. The results show that the synthesized CsPbBr3 NCs are homogeneous in particle size and have good solubility and stability in water. The CsPbBr3 NCs have been utilized as fluorescence probe for rapid detection of hydrogen sulfide (H2S) in human serum. The reaction of H2S with the lead sites on the surface of CsPbBr3 NCs produces lead sulfide (PbS), resulting in the decrease of fluorometric intensity of CsPbBr3 NCs. Our designed fluorescent assay has a linear S2- detecting range of 10 similar to 800 nM with a detection limit of 7.05 nM. The assay was used to determine H2S in human serum with spiked recoveries ranging from 94.98% to 102.69%. This work opens new avenues for the application of halide lead perovskite in different biosensing areas.