Huang Siqi, Yu Zhiming, Zhang Yang, Qi Chusheng, Zhang Shifeng
MOE Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Beijing, China.
Int J Nanomedicine. 2017 Apr 18;12:3181-3191. doi: 10.2147/IJN.S130397. eCollection 2017.
In order to fabricate antimicrobial carboxymethyl chitosan-nanosilver (CMC-Ag) hybrids with controlled silver release, this study demonstrated comparable formation via three synthetic protocols: 1) carboxymethyl chitosan (CMC) and glucose (adding glucose after AgNO), 2) CMC and glucose (adding glucose before AgNO), and 3) CMC only. Under principles of green chemistry, the synthesis was conducted in an aqueous medium exposed to microwave irradiation for 10 minutes with nontoxic chemicals. The structure and formation mechanisms of the three CMC-Ag hybrids were explored using X-ray diffraction, ultraviolet-visible spectroscopy, transmission electron microscopy, and Fourier-transform infrared analyses. Additionally, antimicrobial activity and in vitro silver release of the three synthesized hybrids were investigated in detail. The results revealed that a large number of stable, uniform, and small silver nanoparticles (AgNPs) were synthesized in situ on CMC chains via protocol 1. AgNPs were well dispersed with narrow size distribution in the range of 6-20 nm, with mean diameter only 12.22±2.57 nm. The addition of glucose resulted in greater AgNP synthesis. The order of addition of glucose and AgNO significantly affected particle size and size distribution of AgNPs. Compared to CMC alone and commercially available AgNPs, the antimicrobial activities of three hybrids were significantly improved. Of the three hybrids, CMC-Ag1 synthesized via protocol 1 exhibited better antimicrobial activity than CMC-Ag2 and CMC-Ag3, and showed more effective inhibition of than . Due to strong coordination and electrostatic interactions between CMC and silver and good steric protection provided by CMC, CMC-Ag1 displayed stable and continuous silver release and better performance in retaining silver for prolonged periods than CMC-Ag2 and CMC-Ag3.
为了制备具有可控银释放的抗菌羧甲基壳聚糖-纳米银（CMC-Ag）杂化物，本研究通过三种合成方案展示了类似的形成过程：1）羧甲基壳聚糖（CMC）和葡萄糖（在硝酸银之后添加葡萄糖），2）CMC和葡萄糖（在硝酸银之前添加葡萄糖），以及3）仅CMC。在绿色化学原则下，合成在暴露于微波辐射10分钟的水性介质中使用无毒化学物质进行。使用X射线衍射、紫外可见光谱、透射电子显微镜和傅里叶变换红外分析探索了三种CMC-Ag杂化物的结构和形成机制。此外，还详细研究了三种合成杂化物的抗菌活性和体外银释放。结果表明，通过方案1在CMC链上原位合成了大量稳定、均匀且小的银纳米颗粒（AgNP）。AgNP分散良好，尺寸分布狭窄，范围在6-20nm，平均直径仅为12.22±2.57nm。葡萄糖的添加导致更多的AgNP合成。葡萄糖和硝酸银的添加顺序显著影响AgNP的粒径和尺寸分布。与单独的CMC和市售AgNP相比，三种杂化物的抗菌活性显著提高。在三种杂化物中，通过方案1合成的CMC-Ag1表现出比CMC-Ag2和CMC-Ag3更好的抗菌活性，并且对……的抑制作用比……更有效。由于CMC与银之间的强配位和静电相互作用以及CMC提供的良好空间保护，CMC-Ag1显示出稳定且持续的银释放，并且在长时间保留银方面比CMC-Ag2和CMC-Ag3表现更好。
