Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, Putian, 351100, China; Key Laboratory of Pharmaceutical Analysis and Laboratory Medicine (Putian University), Fujian Province University, Putian, 351100, China
Zhifeng Xu
Department of Cardiothoracic Surgery, Affiliated Hospital of Putian University, Putian University, Putian, 351100, China
Tianhui Liu
Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, Putian, 351100, China; Key Laboratory of Pharmaceutical Analysis and Laboratory Medicine (Putian University), Fujian Province University, Putian, 351100, China
Liwen Chen
Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, Putian, 351100, China
Xiaoling Liu
Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, Putian, 351100, China
Kaiying Chen
Pathology Department, The First Hospital of Putian City, Putian, 351100, China
Chengfei Zhao
Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, Putian, 351100, China; Key Laboratory of Pharmaceutical Analysis and Laboratory Medicine (Putian University), Fujian Province University, Putian, 351100, China; Corresponding author. Department of Pharmacy, School of Pharmacy and Medical Technology, Putian University, 1133 Xueyuan Road, Chengxiang District, Putian, 351100, China.
In this study, nitrogen-sulfur codoped carbon quantum dots (N-S/CQDs) with various functions and properties were synthesized through a one-step method utilizing citric acid and cysteine as reaction substrates. The fluorescence of N-S/CQDs can be specifically quenched by permanganate ion (MnO4−), and the quenched fluorescence can be recovered by the presence of reduced glutathione (GSH). A fluorescence sensing system based on N-S/CQDs@MnO4− was developed and successfully applied for the determination of GSH in pharmaceutical preparations. Additionally, N-S/CQDs demonstrated broad-spectrum antibacterial activity, with minimum inhibitory concentrations of 32 μg/ml against Staphylococcus aureus (gram-positive bacterium) and 64 μg/ml against Escherichia coli (gram-negative bacterium). N-S/CQDs also proved effective for cell imaging, exhibiting excellent biocompatibility. These findings underscore the multifunctional characteristics and promising application potential of N-S/CQDs. Furthermore, this study provides a solid foundation for the development of multifunctional carbon quantum dots and the expansion of their applications in various fields.
