This paper reports the phase separation behavior of ABS films cast on the surfaces of homopelymers or random copolymers.It is found that phase separation of ABS films was induced by the surfaces of the substrate polym...This paper reports the phase separation behavior of ABS films cast on the surfaces of homopelymers or random copolymers.It is found that phase separation of ABS films was induced by the surfaces of the substrate polymers.The relationship between the miscibility of the sub- strate polymers and the phase separation behavior of ABS films was also examined.展开更多
Antimicrobial peptides(AMPs)have been considered as an alternative to small molecule antibiotics since they are difficult to develop antimicrobial resistance.Hyperbranched polylysine(HPL),an AMP mimics,has gained atte...Antimicrobial peptides(AMPs)have been considered as an alternative to small molecule antibiotics since they are difficult to develop antimicrobial resistance.Hyperbranched polylysine(HPL),an AMP mimics,has gained attention due to its broad-spectrum antibacterial activities,but it also suffers from high toxicity.Here we report a facile strategy to engineer the toxicity of HPL by copolymerizing lysine(K)with a hydrophobic amino acid,e.g.,alanine(A),tryptophan(W)or phenylalanine(F),to afford hyperbranched random copolymers.These copolymers have comparable antibacterial activities to HPL while their cytotoxicities and in vivo toxicities are lowered when the type and content of hydrophobic amino acid and the size of copolymers are optimized.The G.mellonella infection model demonstrates that the copolymers are effective against the S.aureus infection in vivo.The copolymers kill the bacteria through the disruption of cell membranes and the bacteria do not develop resistance to the copolymers.展开更多
Amphiphilic graft copolymers consisting of poly（vinyl chloride）（PVC） main chains and poly（4-vinyl pyridine）（P4VP） side chains were synthesized via atom transfer radical polymerization（ATRP） using direct init...Amphiphilic graft copolymers consisting of poly（vinyl chloride）（PVC） main chains and poly（4-vinyl pyridine）（P4VP） side chains were synthesized via atom transfer radical polymerization（ATRP） using direct initiation of chlorine atoms. The successful synthesis of PVC-g-P4 VP graft copolymers was confirmed by Fourier transform infrared spectroscopy（FTIR） and proton nuclear magnetic resonance（1H-NMR）. Transmission electron microscope（TEM） and small angle X-ray scattering（SAXS） analysis showed that PVC-g-P4 VP exhibited microphase-separated, ordered structure with 37.6 nm of domain spacing, which was not observed in neat PVC. For antibacterial applications, the tertiary nitrogen atoms of PVC-gP4 VP was quaternized using 1-bromohexane, as confirmed by FTIR measurements. Bacteria including Escherichia coli（E. coli）, Staphylococcus aureus（S. aureus）, Bacillus cereus（B. cereus）, and Pseudomonas aeruginosa（P. aeruginosa） were completely killed in 24 h on the quaternized PVC-g-P4VP（46% grafting） surface, indicating its excellent antibacterial behavior while it showed to be cytotoxic to mammalian cell.展开更多
Tackling fogging and microbial infection problems related to the endoscope lens remain challenges due to visual disturbances and bacterial threats to human health.Herein,highly transparent antifogging and antibacteria...Tackling fogging and microbial infection problems related to the endoscope lens remain challenges due to visual disturbances and bacterial threats to human health.Herein,highly transparent antifogging and antibacterial coatings were developed in a facile way by thermal curing of zwitterionic copolymers poly(n-butyl methacrylate-co-2-aminoethyl methacrylate-co-sulfobetaine methacrylate)s with 1,3,5-triformylbenzene.Characterizations of surface chemical composition and wettability suggested that the copolymer coatings exhibited amphiphilicity with a hydrophobic surface and internal hydrophilicity.The prepared amphiphilic coating exhibited excellent antifogging properties both in vivo and in vitro.The introduction of hydrophobic n-butyl methacrylate and cationic aminoethylmethacrylate could improve the stability and antibacterial capability of the coating.The growth inhibition rates of the coatings against Staphylococcus aureus and Escherichia coli were up to 99%and the copolymer coatings with the zwitterionic groups had low hemolytic rates less than 3%.The amphiphilic copolymer coatings combined antifogging and antibacterial properties may have a promising potential for applications in biomedical devices.展开更多
文摘This paper reports the phase separation behavior of ABS films cast on the surfaces of homopelymers or random copolymers.It is found that phase separation of ABS films was induced by the surfaces of the substrate polymers.The relationship between the miscibility of the sub- strate polymers and the phase separation behavior of ABS films was also examined.
基金financially supported by the National Natural Science Foundation of China(No.51973212)Department of Science and Technology of Jilin Province(Nos.20210203119SF and 20210203173SF)。
文摘Antimicrobial peptides(AMPs)have been considered as an alternative to small molecule antibiotics since they are difficult to develop antimicrobial resistance.Hyperbranched polylysine(HPL),an AMP mimics,has gained attention due to its broad-spectrum antibacterial activities,but it also suffers from high toxicity.Here we report a facile strategy to engineer the toxicity of HPL by copolymerizing lysine(K)with a hydrophobic amino acid,e.g.,alanine(A),tryptophan(W)or phenylalanine(F),to afford hyperbranched random copolymers.These copolymers have comparable antibacterial activities to HPL while their cytotoxicities and in vivo toxicities are lowered when the type and content of hydrophobic amino acid and the size of copolymers are optimized.The G.mellonella infection model demonstrates that the copolymers are effective against the S.aureus infection in vivo.The copolymers kill the bacteria through the disruption of cell membranes and the bacteria do not develop resistance to the copolymers.
基金financially supported by a National Research Foundation(NRF)grant funded by the Korean government(MEST)through the Core Research Program(2012R1A2A2A02011268)Agriculture Research Center program of Ministry for Food,Agriculture,Forestry,and Fisheries(IPET 112051-3)the Korea CCS R&D Center and the Energy Efficiency&Resources of the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Ministry of Knowledge Economy(20122010100040)
文摘Amphiphilic graft copolymers consisting of poly（vinyl chloride）（PVC） main chains and poly（4-vinyl pyridine）（P4VP） side chains were synthesized via atom transfer radical polymerization（ATRP） using direct initiation of chlorine atoms. The successful synthesis of PVC-g-P4 VP graft copolymers was confirmed by Fourier transform infrared spectroscopy（FTIR） and proton nuclear magnetic resonance（1H-NMR）. Transmission electron microscope（TEM） and small angle X-ray scattering（SAXS） analysis showed that PVC-g-P4 VP exhibited microphase-separated, ordered structure with 37.6 nm of domain spacing, which was not observed in neat PVC. For antibacterial applications, the tertiary nitrogen atoms of PVC-gP4 VP was quaternized using 1-bromohexane, as confirmed by FTIR measurements. Bacteria including Escherichia coli（E. coli）, Staphylococcus aureus（S. aureus）, Bacillus cereus（B. cereus）, and Pseudomonas aeruginosa（P. aeruginosa） were completely killed in 24 h on the quaternized PVC-g-P4VP（46% grafting） surface, indicating its excellent antibacterial behavior while it showed to be cytotoxic to mammalian cell.
基金supported by the National Natural Science Foundation of China(Grant No.51603143)the Natural Science Foundation of Tianjin(Grant Nos.18JCQNJC03800&17JCZDJC37500)。
文摘Tackling fogging and microbial infection problems related to the endoscope lens remain challenges due to visual disturbances and bacterial threats to human health.Herein,highly transparent antifogging and antibacterial coatings were developed in a facile way by thermal curing of zwitterionic copolymers poly(n-butyl methacrylate-co-2-aminoethyl methacrylate-co-sulfobetaine methacrylate)s with 1,3,5-triformylbenzene.Characterizations of surface chemical composition and wettability suggested that the copolymer coatings exhibited amphiphilicity with a hydrophobic surface and internal hydrophilicity.The prepared amphiphilic coating exhibited excellent antifogging properties both in vivo and in vitro.The introduction of hydrophobic n-butyl methacrylate and cationic aminoethylmethacrylate could improve the stability and antibacterial capability of the coating.The growth inhibition rates of the coatings against Staphylococcus aureus and Escherichia coli were up to 99%and the copolymer coatings with the zwitterionic groups had low hemolytic rates less than 3%.The amphiphilic copolymer coatings combined antifogging and antibacterial properties may have a promising potential for applications in biomedical devices.
文摘在氮气保护下,以硝酸铈铵为氧化还原引发剂,冰乙酸为溶剂,通过壳聚糖(CS)与盐酸聚六亚甲基胍盐衍生物(PHGH)的接枝共聚反应,制备出了具有较好水溶性的CS/PHGH材料.采用红外光谱、元素分析对该材料进行了表征,并对其抑菌性实验进行了研究.结果表明,合成的水溶性CS/PHGH对真菌、革兰氏阳性菌与革兰氏阴性菌的抑制作用均优于壳聚糖,尤其对真菌的抑菌效果最灵敏,其最小抑菌浓度(MIC)为0.39 mg.mL-1,抑菌圈直径为21 mm.
