The antibacterial effect of carrying silver B_2O_3-SiO_2-Na_2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimen...The antibacterial effect of carrying silver B_2O_3-SiO_2-Na_2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B_2O_3-SiO_2-Na_2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell's growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.展开更多
The prevalence of cases of antibiotic resistant infections and the limited number of new antibiotics call for new strategies to prevent bacterial infections. In this study, we evaluate the effectiveness of three diffe...The prevalence of cases of antibiotic resistant infections and the limited number of new antibiotics call for new strategies to prevent bacterial infections. In this study, we evaluate the effectiveness of three different compositions of bioactive glass, doped with silver as an antimicrobial agent for potential applications in preventing bacterial infections. The different glasses were formulated to dissolve and release silver at different rates enabling their use in different applications either individually or in combination to achieve a desired effect. Silver oxide (Ag<sub>2</sub>O) was incorporated into various glass formulations and antibacterial effectiveness was measured using radius of inhibition. Each silver-doped glass effectively inhibited the growth of <i>Escherichia coli</i>, <i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i> with radius of inhibition correlating directly with the dissolution rate of the glass—the faster dissolving glass producing the larger radius of inhibition. Suspending particles of the silver containing glass in phosphate buffered saline or fetal calf serum, slowed the dissolution of each glass and extended the effectiveness of the silver containing glass over time (based on size of the radius of inhibition) compared to water. Potential applications of the powdered glass formulations would be to incorporate glasses with different properties into coatings or cosmetics. To investigate the feasibility of these applications, the silver-glass powder was incorporated into polycaprolactone polymer to determine the antibacterial properties of the imbedded glass powder. Based on this investigation, the silver glass formulations reported herein have potential applications in the medical device, dental, pharmaceutical and cosmetic industries.展开更多
Ag/Ga were incorporated into resorbable orthopaedic phosphate bioactive glasses(PBG,containing P,Ca,Mg,Na,and Fe)thin films to demonstrate their potential to limit growth of Staphylococcus aureus and Escherichia coli ...Ag/Ga were incorporated into resorbable orthopaedic phosphate bioactive glasses(PBG,containing P,Ca,Mg,Na,and Fe)thin films to demonstrate their potential to limit growth of Staphylococcus aureus and Escherichia coli in post-operative prosthetic implantation.Dual target consecutive co-sputtering was uniquely employed to produce a 46 nm Ag:PBG composite observed by high resolution TEM to consist of uniformly dispersed~5 nm metallic Ag nano-particles in a glass matrix.Ga^(3+)was integrated into a phosphate glass preform target which was magnetron sputtered to film thicknesses of~400 or 1400 nm.All coatings exhibited high surface energy of 75.4-77.3 mN/m,attributed to the presence of hydrolytic P-O-P structural surface bonds.Degradation profiles obtained in deionized water,nutrient broth and cell culture medium showed varying ion release profiles,whereby Ga release was measured in 1400 nm coating by ICP-MS to be~6,27,and 4 ppm respectively,fully dissolving by 24 h.Solubility of Ag nanoparticles was only observed in nutrient broth(~9 ppm by 24 h).Quantification of colony forming units after 24 h showed encouraging antibacterial efficacy towards both S.aureus(4-log reduction for Ag:PBG and 6-log reduction for Ga-PBG≈1400 nm)and E.coli(5-log reduction for all physical vapour deposited layers)strains.Human Hs27 fibroblast and mesenchymal stem cell line in vitro tests indicated good cytocompatibility for all sputtered layers,with a marginal cell proliferation inertia in the case of the Ag:PBG composite thin film.The study therefore highlights the(i)significant manufacturing development via the controlled inclusion of metallic nanoparticles into a PBG glass matrix by dual consecutive target co-sputtering and(ii)potential of PBG resorbable thin-film structures to incorporate and release cytocompatible/antibacterial oxides.Both architectures showed prospective bio-functional performance for a future generation of endo-osseous implant-type coatings.展开更多
Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(...Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(NH_4)xMo_3O_(10) ·3H_2O nanowires(NWs). Carrying Ag atoms in the lattice and Ag-rich nanoparticles on the surface, the Ag-doped NWs show strong antibacterial effects for a variety of bacteria including E.coli, Staphylococcus aureus, Candida albicans and Aspergil lus niger. By performing systematic comparison experiments, we have proven that the main antibacterial effects are neither resulted from the tiny amount of Ag+ions released from the Ag-doped NWs in aqueous solutions, nor resulted from Ag-rich nanoparticles of fragments of the NWs when they are slowly dissolved in the Martin broth. Instead, the effects are mainly resulted from a contact mechanism, under which, the Ag-doped NWs need to be physically in contact with the bacteria to be eliminated. This is a novel phenomenon observed in the interactions between nanomaterials and live cells, which is worthy of further investigation at the molecular scale. As the Ag-doped NWs are not dissolved in pure water or weak acids, one may find practical antibacterial applications in textile industry and food storage industry for these unique nanomaterials.展开更多
文摘The antibacterial effect of carrying silver B_2O_3-SiO_2-Na_2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B_2O_3-SiO_2-Na_2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell's growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.
文摘The prevalence of cases of antibiotic resistant infections and the limited number of new antibiotics call for new strategies to prevent bacterial infections. In this study, we evaluate the effectiveness of three different compositions of bioactive glass, doped with silver as an antimicrobial agent for potential applications in preventing bacterial infections. The different glasses were formulated to dissolve and release silver at different rates enabling their use in different applications either individually or in combination to achieve a desired effect. Silver oxide (Ag<sub>2</sub>O) was incorporated into various glass formulations and antibacterial effectiveness was measured using radius of inhibition. Each silver-doped glass effectively inhibited the growth of <i>Escherichia coli</i>, <i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i> with radius of inhibition correlating directly with the dissolution rate of the glass—the faster dissolving glass producing the larger radius of inhibition. Suspending particles of the silver containing glass in phosphate buffered saline or fetal calf serum, slowed the dissolution of each glass and extended the effectiveness of the silver containing glass over time (based on size of the radius of inhibition) compared to water. Potential applications of the powdered glass formulations would be to incorporate glasses with different properties into coatings or cosmetics. To investigate the feasibility of these applications, the silver-glass powder was incorporated into polycaprolactone polymer to determine the antibacterial properties of the imbedded glass powder. Based on this investigation, the silver glass formulations reported herein have potential applications in the medical device, dental, pharmaceutical and cosmetic industries.
基金supported by the Engineering and Physical Sciences Research Council[grant number EP/K029592/1]via the Centre for Innovative Manufacturing in Medical Devices(MeDe Innovation)the financial support of the Romanian National Authority for Scientific Research and Innovation,CNCS-UEFISCDI,in the framework of projects PN-Ⅲ-P1-1.1-TE-2016-1501 and PN-Ⅲ-P1-1.1-TE-2019-0463the Core Programme 21 N.
文摘Ag/Ga were incorporated into resorbable orthopaedic phosphate bioactive glasses(PBG,containing P,Ca,Mg,Na,and Fe)thin films to demonstrate their potential to limit growth of Staphylococcus aureus and Escherichia coli in post-operative prosthetic implantation.Dual target consecutive co-sputtering was uniquely employed to produce a 46 nm Ag:PBG composite observed by high resolution TEM to consist of uniformly dispersed~5 nm metallic Ag nano-particles in a glass matrix.Ga^(3+)was integrated into a phosphate glass preform target which was magnetron sputtered to film thicknesses of~400 or 1400 nm.All coatings exhibited high surface energy of 75.4-77.3 mN/m,attributed to the presence of hydrolytic P-O-P structural surface bonds.Degradation profiles obtained in deionized water,nutrient broth and cell culture medium showed varying ion release profiles,whereby Ga release was measured in 1400 nm coating by ICP-MS to be~6,27,and 4 ppm respectively,fully dissolving by 24 h.Solubility of Ag nanoparticles was only observed in nutrient broth(~9 ppm by 24 h).Quantification of colony forming units after 24 h showed encouraging antibacterial efficacy towards both S.aureus(4-log reduction for Ag:PBG and 6-log reduction for Ga-PBG≈1400 nm)and E.coli(5-log reduction for all physical vapour deposited layers)strains.Human Hs27 fibroblast and mesenchymal stem cell line in vitro tests indicated good cytocompatibility for all sputtered layers,with a marginal cell proliferation inertia in the case of the Ag:PBG composite thin film.The study therefore highlights the(i)significant manufacturing development via the controlled inclusion of metallic nanoparticles into a PBG glass matrix by dual consecutive target co-sputtering and(ii)potential of PBG resorbable thin-film structures to incorporate and release cytocompatible/antibacterial oxides.Both architectures showed prospective bio-functional performance for a future generation of endo-osseous implant-type coatings.
基金the NSF of China(Grant No.11074010)the MOST of China(Grant No.2011DFA51450)for financial support
文摘Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(NH_4)xMo_3O_(10) ·3H_2O nanowires(NWs). Carrying Ag atoms in the lattice and Ag-rich nanoparticles on the surface, the Ag-doped NWs show strong antibacterial effects for a variety of bacteria including E.coli, Staphylococcus aureus, Candida albicans and Aspergil lus niger. By performing systematic comparison experiments, we have proven that the main antibacterial effects are neither resulted from the tiny amount of Ag+ions released from the Ag-doped NWs in aqueous solutions, nor resulted from Ag-rich nanoparticles of fragments of the NWs when they are slowly dissolved in the Martin broth. Instead, the effects are mainly resulted from a contact mechanism, under which, the Ag-doped NWs need to be physically in contact with the bacteria to be eliminated. This is a novel phenomenon observed in the interactions between nanomaterials and live cells, which is worthy of further investigation at the molecular scale. As the Ag-doped NWs are not dissolved in pure water or weak acids, one may find practical antibacterial applications in textile industry and food storage industry for these unique nanomaterials.
