The present work aims to combine carbon quantum dots (CQDs) with the good water solubility, biocompatibility, and low toxicity and nano-sized silver sulfide with excellent antibacterial effect in the synthesized composite. The composite was further treated with polyethyleneimine (PEI) and conjugated with graphene oxide (GO). The as-prepared composite Ag₂S–CQDs–PEI–GO exhibits a core of Ag₂S with the size of 20–50 nm and the shell of CQDs with the average particle size of 1.8 nm. The core shell structure is loaded on the template of PEI–GO. Strong antibacterial effect was observed on Ag₂S–CQDs composite against four strands of bacteria Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis), and Pseudomonas aeruginosa (P. aeruginosa). We briefly discussed the bacteriostatic mechanism of the composite. The as-prepared composite has huge potential in the development of biomedicine.

中文翻译：

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新型Ag 2 S–N–CQD复合材料的合成与抑菌作用

本工作旨在将具有良好水溶性，生物相容性和低毒性的碳量子点（CQD）与具有优异抗菌作用的纳米级硫化银结合在合成复合物中。将该复合物进一步用聚乙烯亚胺（PEI）处理并与氧化石墨烯（GO）缀合。制备的复合Ag ₂ S–CQDs–PEI–GO表现出的Ag ₂ S核的粒径为20–50 nm，CQD的壳的平均粒径为1.8 nm。核心壳结构已加载到PEI–GO模板上。在Ag ₂ S-CQDs复合材料上观察到对金黄色葡萄球菌（S. aureus），大肠杆菌的四股链有较强的抗菌作用（大肠杆菌），粪肠球菌（E. faecalis）和铜绿假单胞菌（P. aeruginosa）。我们简要讨论了复合材料的抑菌机理。所制备的复合材料在生物医学的发展中具有巨大的潜力。