The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were i...The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were investigated. The results indicate that the coatings have a full metallurgical bond in coating/substrate interface, and consist mainly ofy-Ni, WC, Cr23C6, Cr7C3, Ni3Si, CrsB3, and FeNi3 phases. The powder composition influences the microstructures and properties of the coatings. The WC content and the hardness of coatings increase with the mass fraction of WC-Co 12 powder. The biomimetic coatings have much higher wear resistance compared with the low carbon steel, which is attributed to the combination of hard WC and chromium carbide particles （bionic units） and soft y-Ni matrix in the coatings. It is favorable to prepare the biomimetic coating by plasma spray welding with the mixed powders （20wt%WC-Col2＋80wt%NiCrBSi） for improving the wear resis- tance of the coating.展开更多
Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address sign...Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address significant shortcomings of conventional therapy,biological barriers remain a challenge in their delivery and accumulation at diseased sites.To achieve long circulation time,immune evasion,and targeted accumulation,conventional nanocarriers need modifications,e.g.,PEGylation,peptide/aptamer attachment,etc.One such modification is a biomimetic coating using cell membrane(CM),which can offer long circulation or targeting,or both.This top-down CM coating process is facile and can provide some advantageous features over surface modification by synthetic polymers.Herein,an overview is provided on the engineering of CM camouflaged polymer nanoparticles.A short section on CM and the development of CM coating technology has been provided.Detailed description of the preparation and characterization of CM camouflaged polymer NPs and their applications in cancer treatment has been reported.A brief comparison between CM coating and PEGylation has been highlighted.Various targeting approaches to achieve tumor-specific delivery of CM coated NPs have been summarized here.Overall,this review will give the readers a nice picture of CM coated polymer NPs,along with their opportunities and challenges.展开更多
Limited surface lubrication and bacterial biofilm formation pose great challenges to biomedical implants.Although hydrophilic lubricated coatings and bacterial resistance coatings have been reported,the harsh and tedi...Limited surface lubrication and bacterial biofilm formation pose great challenges to biomedical implants.Although hydrophilic lubricated coatings and bacterial resistance coatings have been reported,the harsh and tedious synthesis greatly compromises their application,and more importantly,the bacterial resistance property has seldom been investigated in combination with the lubrication property.In this study,bioinspired by the performances of mussel and articular cartilage,we successfully synthesized self-adhesive lubricated coating and simultaneously achieved optimal lubrication and bacterial resistance properties.Additionally,we reported the mechanism of bacterial resistance on the nanoscale by studying the adhesion interactions between biomimetic coating and hydrophilic/hydrophobic tip or living bacteria via atomic force microscopy.In summary,the self-adhesive lubricated coating can effectively enhance lubrication and bacterial resistance performances based on hydration lubrication and hydration repulsion,and represent a universal and facial strategy for surface functionalization of biomedical implants.展开更多
Despite the fact that numerous infection-resistant surfaces have been developed to prevent bacterial colonization and biofilm formation, developing a stable, highly antibacterial and easily produced surface remains a ...Despite the fact that numerous infection-resistant surfaces have been developed to prevent bacterial colonization and biofilm formation, developing a stable, highly antibacterial and easily produced surface remains a technical challenge. As a crucial structural component of biofilm, extracellular DNA（eDNA） can facilitate initial bacterial adhesion, subsequent development, and final maturation. Inspired by the mechanistic pathways of natural enzymes（deoxyribonuclease）, here we report a novel antibacterial surface by employing cerium（Ce（Ⅳ）） ion to mimic theDNA-cleavage ability of natural enzymes. In this process, the coordination chemistry of plant polyphenols and metal ions was exploited to create an in situ metal-phenolic film on substrate surfaces. Tannic acid（TA） works as an essential scaffold and Ce（Ⅳ） ion acts as both a cross-linker and a destructor of eDNA. The Ce（Ⅳ）-TA modified surface exhibited highly enhanced bacteria repellency and biofilm inhibition when compared with those of pristine or Fe（Ⅲ）-TA modified samples. Moreover, the easily produced coatings showed high stability under physiological conditions and had nontoxicity to cells for prolonged periods of time. This as-prepared DNA-cleavage surface presents versatile and promising performances to combat biomaterial-associated infections.展开更多
文摘The NiCrBSi/WC biomimetic coatings were prepared on the low carbon steel substrate by plasma spray welding with mixed powders （WC-Col2＋NiCrBSi） based on the bionic principles, and the coating characteristics were investigated. The results indicate that the coatings have a full metallurgical bond in coating/substrate interface, and consist mainly ofy-Ni, WC, Cr23C6, Cr7C3, Ni3Si, CrsB3, and FeNi3 phases. The powder composition influences the microstructures and properties of the coatings. The WC content and the hardness of coatings increase with the mass fraction of WC-Co 12 powder. The biomimetic coatings have much higher wear resistance compared with the low carbon steel, which is attributed to the combination of hard WC and chromium carbide particles （bionic units） and soft y-Ni matrix in the coatings. It is favorable to prepare the biomimetic coating by plasma spray welding with the mixed powders （20wt%WC-Col2＋80wt%NiCrBSi） for improving the wear resis- tance of the coating.
文摘Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address significant shortcomings of conventional therapy,biological barriers remain a challenge in their delivery and accumulation at diseased sites.To achieve long circulation time,immune evasion,and targeted accumulation,conventional nanocarriers need modifications,e.g.,PEGylation,peptide/aptamer attachment,etc.One such modification is a biomimetic coating using cell membrane(CM),which can offer long circulation or targeting,or both.This top-down CM coating process is facile and can provide some advantageous features over surface modification by synthetic polymers.Herein,an overview is provided on the engineering of CM camouflaged polymer nanoparticles.A short section on CM and the development of CM coating technology has been provided.Detailed description of the preparation and characterization of CM camouflaged polymer NPs and their applications in cancer treatment has been reported.A brief comparison between CM coating and PEGylation has been highlighted.Various targeting approaches to achieve tumor-specific delivery of CM coated NPs have been summarized here.Overall,this review will give the readers a nice picture of CM coated polymer NPs,along with their opportunities and challenges.
基金supported by National Natural Science Foundation of China(52022043)Tsinghua University Initiative Scientific Research Program(20197050026)+2 种基金Precision Medicine Foundation,Tsinghua University,China(10001020120)Capital’s Funds for Health Improvement and Research(2020-2Z-40810)Research Fund of State Key Laboratory of Tribology,Tsinghua University,China(SKLT2020C11).
文摘Limited surface lubrication and bacterial biofilm formation pose great challenges to biomedical implants.Although hydrophilic lubricated coatings and bacterial resistance coatings have been reported,the harsh and tedious synthesis greatly compromises their application,and more importantly,the bacterial resistance property has seldom been investigated in combination with the lubrication property.In this study,bioinspired by the performances of mussel and articular cartilage,we successfully synthesized self-adhesive lubricated coating and simultaneously achieved optimal lubrication and bacterial resistance properties.Additionally,we reported the mechanism of bacterial resistance on the nanoscale by studying the adhesion interactions between biomimetic coating and hydrophilic/hydrophobic tip or living bacteria via atomic force microscopy.In summary,the self-adhesive lubricated coating can effectively enhance lubrication and bacterial resistance performances based on hydration lubrication and hydration repulsion,and represent a universal and facial strategy for surface functionalization of biomedical implants.
基金financially supported by the Research Program Funds of Jilin University (Nos.419080500665 and 451170301076)the Natural Science Foundation of Shandong Province (No.ZR2015EM036)
文摘Despite the fact that numerous infection-resistant surfaces have been developed to prevent bacterial colonization and biofilm formation, developing a stable, highly antibacterial and easily produced surface remains a technical challenge. As a crucial structural component of biofilm, extracellular DNA（eDNA） can facilitate initial bacterial adhesion, subsequent development, and final maturation. Inspired by the mechanistic pathways of natural enzymes（deoxyribonuclease）, here we report a novel antibacterial surface by employing cerium（Ce（Ⅳ）） ion to mimic theDNA-cleavage ability of natural enzymes. In this process, the coordination chemistry of plant polyphenols and metal ions was exploited to create an in situ metal-phenolic film on substrate surfaces. Tannic acid（TA） works as an essential scaffold and Ce（Ⅳ） ion acts as both a cross-linker and a destructor of eDNA. The Ce（Ⅳ）-TA modified surface exhibited highly enhanced bacteria repellency and biofilm inhibition when compared with those of pristine or Fe（Ⅲ）-TA modified samples. Moreover, the easily produced coatings showed high stability under physiological conditions and had nontoxicity to cells for prolonged periods of time. This as-prepared DNA-cleavage surface presents versatile and promising performances to combat biomaterial-associated infections.
