In this work,a novel coating with a non-antibiotic agent for inhibiting Gram-positive bacteria and promoting osteogenesis was prepared on zinc-aluminium alloy(ZA6-1)via mussel mimetic polydopamine(PDA)containing lysoz...In this work,a novel coating with a non-antibiotic agent for inhibiting Gram-positive bacteria and promoting osteogenesis was prepared on zinc-aluminium alloy(ZA6-1)via mussel mimetic polydopamine(PDA)containing lysozyme(LYS)and parathyroid hormone(PTH).The results indicate that as-deposited coatings can efficiently decrease the degradation rate of ZA6-1 from 0.52 to 0.16 mm/year,and the addition of LYS weakens the coating resistance,while the addition of PTH enhances the coating resis-tance.In spite that no obvious inhibition of Escherichia coli is observed,the coated zinc alloys show good in vitro antibacterial performance against Staphylococcus aureus.Compared with ZA6-1 zinc alloys,the increase of antibacterial efficacy reaches 86.9%-90.1%.Furthermore,the lower hydrophilicity(26.4°),higher osteoblast cell viability(>100%),good osteoblast cell morphology and better osteoblast cell differentiation(ALP=107.7%)for PDA-LYS/PTH coated samples support that as-prepared coating is promising for modifying biodegradable zinc implants.展开更多
Diamond like carbon(DLC)films with different C-C sp2/sp3 ratios were prepared by tuning the N2 flow rate in a filtered cathodic vacuum arc(FCVA)system.The increase of N2 flow rate facilitated the increase of C-C sp2/s...Diamond like carbon(DLC)films with different C-C sp2/sp3 ratios were prepared by tuning the N2 flow rate in a filtered cathodic vacuum arc(FCVA)system.The increase of N2 flow rate facilitated the increase of C-C sp2/sp3 ratio(1.09-2.66),the growth of particle size(0.78-1.58 nm)and the improvement of surface roughness.The SBF immersion results,as well as WCAs(77.57°~71.71°),hemolysis rate(0.14-1.00%)and cytotoxicity level(0)demonstrated that the as-fabricated DLC film was promising for biomedical application.As a result of surface charge effect,the apatite layers formed in the SBF increased with the increase of C-C sp2/sp3 ratio until 1.74 and then showed a tiny decrease during 1.74-2.66.A raise of hemolysis and cytotoxicity was observed when sp2/sp3 ratio was increased.Moreover,a decrease of friction coefficient of Si surface induced by increasing sp2/sp3 ratio was respectively evidenced in ambient air and SBF lubrication environments.展开更多
基金National Natural Science Foundation of China,Grant/Award Number:52271250Venture and Innovation Support Program for Chongqing Overseas Returnees,Grant/Award Number:cx2021106Natural Science Foundation of Chongqing Municipality,Grant/Award Number:CSTB2023NSCQ-MSX0977。
文摘In this work,a novel coating with a non-antibiotic agent for inhibiting Gram-positive bacteria and promoting osteogenesis was prepared on zinc-aluminium alloy(ZA6-1)via mussel mimetic polydopamine(PDA)containing lysozyme(LYS)and parathyroid hormone(PTH).The results indicate that as-deposited coatings can efficiently decrease the degradation rate of ZA6-1 from 0.52 to 0.16 mm/year,and the addition of LYS weakens the coating resistance,while the addition of PTH enhances the coating resis-tance.In spite that no obvious inhibition of Escherichia coli is observed,the coated zinc alloys show good in vitro antibacterial performance against Staphylococcus aureus.Compared with ZA6-1 zinc alloys,the increase of antibacterial efficacy reaches 86.9%-90.1%.Furthermore,the lower hydrophilicity(26.4°),higher osteoblast cell viability(>100%),good osteoblast cell morphology and better osteoblast cell differentiation(ALP=107.7%)for PDA-LYS/PTH coated samples support that as-prepared coating is promising for modifying biodegradable zinc implants.
基金support from National Natural Science Foundation of China(Grant 51801164)Besides,this work is jointly supported by Fundamental Research Funds for the Central Universities(Grant XDJK2020C005)+1 种基金National Training Program of Innovation and Entrepreneurship for Undergraduates(Grant 201810635068)the Venture&Innovation Support Program for Chongqing Overseas Returnees(Grant cx2018080).
文摘Diamond like carbon(DLC)films with different C-C sp2/sp3 ratios were prepared by tuning the N2 flow rate in a filtered cathodic vacuum arc(FCVA)system.The increase of N2 flow rate facilitated the increase of C-C sp2/sp3 ratio(1.09-2.66),the growth of particle size(0.78-1.58 nm)and the improvement of surface roughness.The SBF immersion results,as well as WCAs(77.57°~71.71°),hemolysis rate(0.14-1.00%)and cytotoxicity level(0)demonstrated that the as-fabricated DLC film was promising for biomedical application.As a result of surface charge effect,the apatite layers formed in the SBF increased with the increase of C-C sp2/sp3 ratio until 1.74 and then showed a tiny decrease during 1.74-2.66.A raise of hemolysis and cytotoxicity was observed when sp2/sp3 ratio was increased.Moreover,a decrease of friction coefficient of Si surface induced by increasing sp2/sp3 ratio was respectively evidenced in ambient air and SBF lubrication environments.