Dynamic Reversible Bismuth Sulfide Nanoparticles For The Treatment Of Drug-Resistant Bacterial Infection

Bacterial infection has become a major cause of high mortality worldwide,and previous studies have been mainly treated with antibiotics.However,due to the resistance of more and more bacteria to existing antibiotics,the treatment based on antibiotics has been unable to meet the treatment of drug-resistant bacteria,which has a significant impact on people’s normal life and even poses a great threat to life and health.How to design and develop new drugs to overcome drug-resistant bacteria has become an urgent scientific problem to be solved.Metal nanomaterials have various properties,such as photoelectromagnetization,and have been widely used in the field of biomedicine.Bismuth-based nanomaterials are widely used in the treatment of bacterial infections due to their strong photothermal properties,good biocompatibility and safety.Compared with small molecular antibiotics,gas therapy is a safe and effective treatment,the development of antibacterial therapy has a great application prospect.Among them,nitric oxide（NO）,as a lipophilic biological signal molecule,can cross the plasma membrane and spread to neighboring cells,as a gas"star molecule",it is a broad-spectrum antibacterial candidate molecule.In this study,acid-responsive bismuth sulfide nanoparticle assemblies Bi₂S₃@SNP NPs loaded with nitric oxide donor sodium nitroprusside（SNP）were designed and synthesized.On the one hand,the good photothermal properties of bismuth-based nanomaterials can be used to achieve antibacterial purposes through photothermal therapy.At the same time,the photosensitive NO donor SNP releases NO under the irradiation of near-infrared light,which cooperates with photothermal to exert antibacterial effect.In this study,the synthesized Bi₂S₃@SNP NPs was characterized by TEM,DLS and XPS,which proved that the synthesized Bi₂S₃@SNP NPs was successfully synthesized.It is also proved that the nanoparticle assembly has good photothermal properties and the ability to load nitric oxide donors.To verify the antibacterial effect of synthesized Bi₂S₃@SNP NPs on drug-resistant bacteria,clinical multidrug resistant strains were screened from sputum of clinical patients,and the antibacterial effect of synthesized Bi₂S₃@SNP NPs on multidrug resistant bacteria was studied.The experimental results show that Bi₂S₃@SNP NPs has good antibacterial effect on sensitive and drug-resistant Gram-positive bacteria and Gram-negative strains under near-infrared irradiation,which provides theoretical support and exploration methods for clinical treatment of drug-resistant bacterial infections.