生物多聚糖诱导的金纳米粒子的合成与表征

在不引入其它还原剂和稳定剂的情况下, 加热天然生物多聚糖——壳聚糖(CHIT)和氯金酸的混合溶液, 一步反应制备高稳定性的金纳米粒子(GNPs). 采用紫外光谱、红外光谱、热重分析和透射电镜对产品进行了表征. 结果表明: 改变CHIT的浓度能够调控GNPs的光学和结构性质; 老化-时效处理可以作为粒子增长过程中的一个调控手段. 动力学数据证明GNPs的时效处理过程是一个CHIT诱导的自催化生长过程; 红外谱中1713.3 cm^－1左右出现的新的吸收带, 可能是作为还原剂参加反应的壳聚糖或者它的水解产物分子中的部分羟基被氧化为羰基引起的. 本文工作也为进一步阐明目前还处于探索阶段的纳米粒子的形成机制以及实现其工业化绿色生产提供了可能性.

Polysaccharide-induced Synthesis of Gold Nanoparticles and Their Characterization

Highly stable gold nanoparticles (GNPs) have been prepared by heating chitosan (CHIT) and HAuCl4 aqueous solution without the additional step of introducing other reducing agents and protecting agents. The samples were characterized by UV-Vis, FI-IR, TGA-DTA and TEM. Results indicated that the properties of resultant GNPs could be controlled by altering the CHIT concentration and the aging could be used as a control parameter in GNPs growth. Kinetic results suggested that the GNPs growth during aging should be a CHIT-mediated autocatalytic process. Fourier transform infrared spectroscopy (FTIR) showed that the hydroxyl in molecular CHIT or its hydrolytic product was oxidized to carbonyl groups, resulting in the formation of GNPs. Moreover, the abounding existence of raw materials made it amenable to a green industrial production and our study may help to clarify some of the obscure mechanisms of nanoparticle formation in solution at present.