Two-dimensional copper metal-organic frameworks as antibacterial agents for biofilm treatment

Metal-organic frameworks(MOFs)composed of functional metal ions/clusters and suitable bridging ligands are highly designable,which have shown excellent catalytic activity as nanozymes and are promising for antibacterial therapy.Herein,twodimensional(2D)copper MOF nanosheets(Cu-MOF NSs)as effective antibacterial agents were prepared through a simple onestep method.The 2D Cu-MOF NSs displayed a peroxidase-like activity toward H_(2)O_(2)decomposition into highly cytotoxic hydroxyl radicals(·OH).Notably,the 2D morphology of Cu-MOF NSs provides a high density of Cu^(2+)/Cu^(+)surface active sites,which could efficiently oxidize the proteins and lipids on the bacterial surface and induce the death of bacteria.It is found that the as-prepared 2D Cu-MOF NSs exhibited antibacterial properties against Staphylococcus aureus(S.aureus)and could efficiently eradicate the biofilm of S.aureus.Up to 99.9%bacteria were killed at a Cu-MOF concentration of 4μg/m L.This study opens a new avenue for the design of MOF-based antibacterial agents to combat pathogenic bacterial infections.

Developments for collagen hydrolysates as a multifunctional antioxidant in biomedical domains

Antioxidant collagen hydrolysates refers to the peptides mixture with antioxidant properties identified from hydrolyzed collagen.Due to its specific structural,biological and physicochemical properties,collagen hydrolysates have been explored as a multifunctional antioxidant in the biomedical field.In this review,we summarize recent advances in antioxidant collagen hydrolysates development.Initially,the preparation process of antioxidant collagen hydrolysates is introduced,including the production and separation methods.Then the effects and the mechanisms of amino acid composition and collagen peptide structure on the antioxidant activity of collagen hydrolysates are reviewed.Finally,the applications of antioxidant collagen hydrolysates in biomedical domains are summarized,with critical discussions about the advantages,current limitations and challenges to be resolved in the future.

NIR-Ⅱ responsive Janus nanoparticles amplify immunogenic cell death for enhanced cancer immunotherapy

Immunotherapy brings new hope for tumor treatment by inducing immunogenic cell death(ICD)of tumor cells.However,insufficient immunogenicity and low immune response rate greatly limit antitumor immunity.Herein,by optimizing the composition and morphology,the rational design of Janus nanoparticles composed of Fe_(3)O_(4) nanospheres and SiO_(2)nanorods was realized for enhanced cancer immunotherapy through amplified ICD.After glucose oxidase(GOx)was loaded by the Janus nanoparticles,the resultant M-FS-GOx consumes glucose at tumor sites to generate gluconic acid and hydrogen peroxide(H_(2)O_(2))for starvation therapy while the H_(2)O_(2)supply promotes the production of highly toxic·OH to achieve effective chemodynamic therapy(CDT).Under a 1064 nm light irradiation,the photothermal effect of M-FS-GOx enhances the enzyme activity of GOx for improved starvation therapy.Furthermore,both tumor-associated antigens released during the process of ICD and the intrinsic immunoadjuvant property of M-FS-GOx stimulate dendritic cell maturation to activate antitumor immune responses.This work provides a promising strategy for the construction of Janus nanoparticles to achieve enhanced cancer immunotherapy through combination therapy-amplified ICD.

Biomedical polymers: synthesis, properties, and applications

Biomedical polymers have been extensively developed for promising applications in a lot of biomedical fields, such as therapeutic medicine delivery, disease detection and diagnosis, biosensing, regenerative medicine, and disease treatment. In this review, we summarize the most recent advances in the synthesis and application of biomedical polymers, and discuss the comprehensive understanding of their property-function relationship for corresponding biomedical applications. In particular, a few burgeoning bioactive polymers, such as peptide/biomembrane/microorganism/cell-based biomedical polymers, are also introduced and highlighted as the emerging biomaterials for cancer precision therapy. Furthermore, the foreseeable challenges and outlook of the development of more efficient, healthier and safer biomedical polymers are discussed. We wish this systemic and comprehensive review on highlighting frontier progress of biomedical polymers could inspire and promote new breakthrough in fundamental research and clinical translation.