纳米银/介孔氧化硅复合材料的制备及其抗菌性能

Preparation of nano-silver/mesoporous silica composite materials and its antibacterial properties

【目的】为了解决传统的木材银离子抗菌剂中的Ag^(+)易氧化导致其抗菌耐久性有限以及新型纳米银抗菌剂的AgNPs易团聚等问题,制备了一种新型纳米银/介孔氧化硅(Ag/MCM-41-NH_(2))复合抗菌材料。【方法】选取表面氨基改性的介孔氧化硅(MCM-41)作为Ag^(+)的载体,将Ag^(+)负载到改性载体上,并将其原位绿色还原成纳米银(AgNPs)。采用SEM、TEM、N_(2)吸附–脱附、XPS、XRD、FTIR和ICP-MS等手段分析了复合抗菌剂的表面形貌、结构和Ag^(+)的缓释性能。使用抑菌圈法和振荡法测试了复合抗菌剂的抗菌活性,分析了其抗菌性能和抗菌耐久性。【结果】改性后的MCM-41由于表面接枝了大量的氨基,可以与Ag^(+)发生接枝,还原的AgNPs成功负载在MCM-41内部,呈均匀圆球状,分散均匀。抗菌试验和Ag^(+)缓释结果表明,Ag^(+)/MCM-41-NH_(2)和Ag/MCM-41-NH_(2)对金黄色葡萄球菌和大肠杆菌的初始抗菌率均可以达到99.00%以上。但放置90 d后,Ag^(+)/MCM-41-NH_(2)的Ag^(+)流失率为25.00%,对金黄色葡萄球菌和大肠杆菌的抗菌率分别下降到88.75%和79.10%,而Ag/MCM-41-NH_(2)的Ag^(+)流失率降低到5.10%,且对金黄色葡萄球菌和大肠杆菌的抗菌率仍保持在98.93%和96.93%的较高水平。【结论】AgNPs在载体MCM-41-NH_(2)上均匀分散,制备的Ag/MCM-41-NH_(2)复合抗菌剂具有良好的抗菌性能和抗菌耐久性。

[Objective] The traditional Ag^(+) wood antibacterial agents have the problem that Ag^(+) is easy to be oxidized,which leads to its limited antimicrobial durability,and the silver nanoparticles in novel nanosilver antibacterial agent also have the problem of easy aggregation.In order to solve these problems,a novel silver-loaded silica(Ag/MCM-41-NH_(2)) composite antibacterial material was prepared in this paper.[Method] The composite material was prepared by embedding silver ions into the modified carrier and insitu green reduction to AgNPs.SEM,TEM,adsorption desorption of N_(2),XPS,XRD,FTIR and ICP-MS were used to analyze the surface morphology,structure and slow release feature of it.The inhibition zone method and oscillating method were used to analyze the antibacterial properties and antibacterial durability of composite antibacterial agents.[Result] The modified MCM-41 was successfully grafted with a large number of –NH_(2),which could graft with Ag^(+).In addition,the spherical AgNPs were uniformly loaded inside the MCM-41-NH_(2).The results of bacteriostatic test showed that the initial antibacterial rate of Ag^(+)/MCM-41-NH_(2) and Ag/MCM-41-NH_(2) against Staphylococcus aureus and Escherichia coli was over99.00%.However,the loss rate of Ag^(+) in Ag^(+)/MCM-41-NH_(2) was 25.00% and its antibacterial rates against S.aureus and E.coli were decreased to 88.75% and 79.10% after 90 d,while the loss rate of Ag^(+) in Ag^(+)/MCM-41-NH_(2) was 5.10% and its antibacterial rate against S.aureus and E.coli remained at a high level of 98.93% and 96.93%.[Conclusion] Ag-NPs can be uniformly dispersed on the carrier MCM-41-NH_(2),and the Ag/MCM-41-NH_(2) composite antibacterial agent has good antibacterial property and antibacterial durability.