高浓度纳米银的制备及其抗菌效果评价

Preparation of high concentration nano-silver and its antibacterial ability evaluation

为了制备具有良好稳定性的高浓度纳米银,采用紫外-可见光谱、动态光散射和透射电镜为主要手段研究了不同用量的苯扎溴铵(保护剂)对纳米银胶团粒径和稳定性的影响;然后,将稳定性最好的高浓度纳米银与异噻唑啉酮复配制备了纳米银抗菌剂,并对其抗细菌和抗真菌能力进行了评价。实验结果表明,苯扎溴铵用量过少时不足以完全负载纳米银,用量过多时也会对其稳定性产生负面影响,用量适中才能制得粒径均一、胶团稳定的纳米银溶液。当苯扎溴铵用量为8×10^-3 g/mL时,所制备的纳米银溶液具有较好的稳定性,平均粒径约30 nm,银浓度为原配方的10^倍,达2.4×10^-4 g/mL。该纳米银与异噻唑啉酮按质量比10^0∶0.8复配后制得的纳米银抗菌剂具有广谱、高效的抗菌效果,对大肠杆菌的最小抑菌浓度仅为1.0μg/mL,对金黄色葡萄球菌的最小抑菌浓度为2.0μg/mL,对黑曲霉和粘性红圆酵母的最小抑菌浓度为4.0μg/mL。总之,通过增加苯扎溴铵用量的方法可以大幅提高纳米银浓度,有利于纳米银抗菌剂的产业化和推广应用。

In order to prepare concentration nano-silver with proper stability,UV-Vis,dynamic light scattering and transmission electron microscope were used to character the influence of benzalkonium bromide(protecting agent)dosages on nano-silver particle size and stability.Then,the most stable nano-silver with high concentration was mixed with isothiazolinone to prepare nono-silver antibacterial agent,and antibacterial ability of the agent was also evaluated.The results indicated that low concentration benzalkonium bromide was not able to load with nano-silver and too high concentration also had negative effect on nano-silver stability.The nano-silver solution with uniform particle size and excellent stability was prepared under proper benzalkonium bromide.The nano-silver with silver concentration of 2.4×10^-4 g/mL(10^ times higher than prior)was produced when benzalkonium bromide dosage was 8×10^-3 g/mL,in which nano-silver particle size was around 30 nm and the solution was stable enough.The obtained nano-silver was mixed with isothiazolinone based on weight ratio 10^0∶0.8.The nono-silver antibacterial agent had effective and broad antimicrobial ability.The minimal inhibitory concentration for Escherichia coli,Staphylococcus aureus,Rhodotorula mucilaginosa and Aspergillus niger was 1.0,2.0,4.0 and 4.0μg/mL respectively.Increasing benzalkonium bromide(protecting agent)dosages could promote nano-silver concentration.Consequently,it would benefit for nano-silver antibacterial agent industrialization and marketization.