Polydopamine/poly(sulfobetaine methacrylate)Co-deposition coatings triggered by CuSO_(4)/H_(2)O_(2)on implants for improved surface hemocompatibility and antibacterial activity

Implanted biomaterials such as medical catheters are prone to be adhered by proteins,platelets and bacteria due to their surface hydrophobicity characteristics,and then induce related infections and thrombosis.Hence,the development of a versatile strategy to endow surfaces with antibacterial and antifouling functions is particularly significant for blood-contacting materials.In this work,CuSO_(4)/H_(2)O_(2)was used to trigger polydopamine(PDA)and poly-(sulfobetaine methacrylate)(PSBMA)co-deposition process to endow polyurethane(PU)antibacterial and antifouling surface(PU/PDA(Cu)/PSBMA).The zwitterions contained in the PU/PDA(Cu)/PSBMA coating can significantly improve surface wettability to reduce protein adsorption,thereby improving its blood compatibility.In addition,the copper ions released from the metal-phenolic networks(MPNs)imparted them more than 90%antibacterial activity against E.coli and S.aureus.Notably,PU/PDA(Cu)/PSBMA also exhibits excellent performance in vivo mouse catheter-related infections models.Thus,the PU/PDA(Cu)/PSBMA has great application potential for developing multifunctional surface coatings for blood-contacting materials so as to improve antibacterial and anticoagulant properties.

Cyanobacteria-based self-oxygenated photodynamic therapy for anaerobic infection treatment and tissue repair

Photodynamic therapy(PDT)is an important technique to deal with drug-resistant bacterial infections in the post-antibiotic era.However,the hypoxic environment in intractable infections such as refractory keratitis and periodontitis,makes PDT more difficult.In this work,spontaneous oxygen-producing cyanobacteria were used as the carrier of photosensitizer(Ce6),and ultrasmall Cu_(5.4)O nanoparticles(Cu_(5.4)O USNPs)with catalase activity for infection and inflammation elimination and rapid tissue repair(CeCycn-Cu_(5.4)O).The loading of Ce6 and Cu_(5.4)O USNPs onto cyanobacteria surface were confirmed by transmission electron microscopy,nano particle size analyzer,scanning electron microscopy.In vitro sterilization and biofilm removal experiments demonstrated that the restriction of hypoxic environment to PDT was significantly alleviated due to the oxygen production of cyanobacteria.Under laser irradiation,the close transfer of energy photons to oxygen produced by cyanobacteria reduced more than 90% of Ce6 dosages(660 nm,200 mW/cm^(2),2 min).It is worth mentioning that both rapid sterilization through PDT and long-term oxidized free radicals elimination were achieved by adjusting the ratio of Ce6 and Cu_(5.4)O USNPs.Both periodontitis and refractory keratitis animal models proved the excellent self-oxygenation enhanced antibacterial property and promotion of tissue repair.

Tumor-responsive copper-activated disulfiram for synergetic nanocatalytic tumor therapy

Exploring alternative biomedical use of traditional drugs in different disease models is highly important as it can reduce the cost of drug development and overcome several critical issues of traditional chemodrugs such as low chemotherapeutic efficiency,severe side effect,and drug resistance.Disulfiram(DSF),a clinically approved alcohol-aversion drug,was recently demonstrated tofeature tumor-growth suppression effect along with the co-administration of Cu^(2+)species,but direct Cu^(2+)administration mode might cause severe toxicity originating from low Cu^(2+)accumulation into the tumor and nonspecific Cu^(2+)distribution-induced cytotoxicity.Based on the intriguing drug-delivery performance of nanoscale metal-organic frameworks(MOFs),we herein construct HKUST nMOFs as the Cu^(2+)self-supplying nanocarriers for efficient delivery of the D SF drug.The mildly acidic condition of tumor microenvironment initially triggered the release of Cu ions from HKUST nMOFs,which further reacted with the encapsulated DSF toform toxic Cu(DDTC)2(activation)for tumor chemotherapy.Especially,during the Cu(DDTC)2 complexation,Cu^(+)species were formed concomitantly,triggering the intratumoral nanocatalytic therapy for the generation of reactive oxygen species to synergistically destroying the tumor cells/tissue.As a result,synergetic tumor-responsive chemotherapy and nanocatalytic therapy are enabled by DSF@HKU ST nanodrugs,as demonstrated by the dominant anticancer efficacy with satisfied biocompatibility both in vitro and in vivo.The present work offers a sophisticated strategy for tumor-responsive nontoxic-to-toxic therapeutic with high biocompatibility.

Reversible grafting of antibiotics onto contact lens mediated by labile chemical bonds for smart prevention and treatment of corneal bacterial infections

Eye trauma, decreased immunity, and contact lens wear often cause serious bacterial infections and irreversible corneal damage. To realize the responsive release of antibiotics such as gentamicin sulfate(GS), a novel antibacterial contact lens was constructed through self-assembly of antibiotics loaded ADAGS/PEI(polyethyleneimine) multilayer films on the surface. Both in vitro and in vivo antibacterial tests demonstrated high efficient and fast antibacterial property based on the smart responsive to bacterial infections and reversible drug loading and release.

Corrigendum to“Polydopamine/poly(sulfobetaine methacrylate)Co-deposition coatings triggered by CuSO4/H2O2 on implants for improved surface hemocompatibility and antibacterial activity”[Bioactive materials 6(2021)2546-2556]

The authors regret to inform that Fig.3f is incorrect in the original article.A part of images of platelet adhesion on the PU and PU/PDA seemed to be duplicated with that on PU/PDA(Cu)/PSBMA surface.The authors had checked the original images and found the images were mistakenly taken from the same sample of PU/PDA(Cu)/PSBMA with continuous imaging.This correction does not change any description,results or conclusions of the original paper.