纳米银的可控制备及其抗菌性研究
发布时间：2018-08-15 18:27
【摘要】：球形纳米银具有良好的广谱抗菌性和高安全性。其形貌和尺寸分布是影响其物理化学性质和功能的主要因素,因此纳米银的可控制备是近年来研究的热点方向之一。本论文采用液相化学还原法,以来源广泛、无毒的天然产物壳聚糖为保护剂,葡萄糖为还原剂,硝酸银为银前驱体,研究了在水相中制备球形纳米银的影响因素,探讨了可控制备球形纳米银的方法,并考察了球形纳米银的抗菌性能。本论文对液相化学还原法的反应条件进行了一系列单因素实验,采用紫外可见光谱仪、透射电子显微镜和x射线衍射等技术确定了各反应条件对球形纳米银制备过程的影响,并优化了制备工艺。反应体系处于弱碱性(pH=7.30～8.30),反应温度为60℃,壳聚糖/AgNO3质量比为980,AgNO3浓度0.01～0.04 mol/L, AgNO3/葡萄糖摩尔比为1,反应时间8h时有利于生成单分散、小尺寸的稳定球形纳米银胶体。FTIR光谱表明壳聚糖对球形纳米银的保护主要源于分子中-NH2中的N与银原子进行配位,使球形纳米银不易团聚沉降。本研究发展了一种操作简单、在水相中可控合成球形纳米银的方法。通过向液相还原体系中引入不同尺寸的球形纳米银为晶种,合成了一系列尺寸均一的球形纳米银。在制备过程中,发现随着加入的晶种粒径的增大,制备的球形纳米银粒径同步增大,可以从6 nm、9 nm、12 nm依次递增至25 nm,说明在晶体生长过程中保持银原子处于较低浓度是尺寸可控合成的关键。采用Optical Density 600法研究了球形纳米银的抗菌性能。发现球形纳米银对金黄色葡萄球菌(S. aureus)口大肠杆菌(E. coil)都具有优异的抗菌性能,尤其是针对E. coil。在相同球形纳米银浓度下,其抗菌性随着其粒径的增加而迅速降低,小粒径球形纳米银具有更强的抗菌性；对同一种细菌,同一粒径的球形纳米银的抗菌性随着银含量的提高迅速提高。与自制的PVP-球形纳米银、AgNO3和壳聚糖相比,以壳聚糖为保护剂的球形纳米银抗菌性最优。
[Abstract]:Spherical silver nanoparticles have good broad-spectrum antibacterial properties and high safety. The morphology and size distribution are the main factors affecting the physical and chemical properties and functions of silver nanoparticles, so the controllable preparation of silver nanoparticles is one of the hot research directions in recent years. In this paper, the liquid phase chemical reduction method was used to study the factors influencing the preparation of spherical silver nanoparticles in aqueous phase with chitosan, a non-toxic natural product, as protective agent, glucose as reducing agent and silver nitrate as precursor. The method of controllable preparation of spherical silver nanoparticles was discussed, and the antibacterial properties of spherical silver nanoparticles were investigated. In this paper, a series of single-factor experiments were carried out on the reaction conditions of liquid-phase chemical reduction method. The effects of the reaction conditions on the preparation of spherical silver nanoparticles were determined by UV-Vis spectroscopy, transmission electron microscope and X-ray diffraction. The preparation process was optimized. The reaction system is in weak basic (pH=7.30~8.30), the reaction temperature is 60 鈩，
本文编号：2185040
[Abstract]:Spherical silver nanoparticles have good broad-spectrum antibacterial properties and high safety. The morphology and size distribution are the main factors affecting the physical and chemical properties and functions of silver nanoparticles, so the controllable preparation of silver nanoparticles is one of the hot research directions in recent years. In this paper, the liquid phase chemical reduction method was used to study the factors influencing the preparation of spherical silver nanoparticles in aqueous phase with chitosan, a non-toxic natural product, as protective agent, glucose as reducing agent and silver nitrate as precursor. The method of controllable preparation of spherical silver nanoparticles was discussed, and the antibacterial properties of spherical silver nanoparticles were investigated. In this paper, a series of single-factor experiments were carried out on the reaction conditions of liquid-phase chemical reduction method. The effects of the reaction conditions on the preparation of spherical silver nanoparticles were determined by UV-Vis spectroscopy, transmission electron microscope and X-ray diffraction. The preparation process was optimized. The reaction system is in weak basic (pH=7.30~8.30), the reaction temperature is 60 鈩，
本文编号：2185040
本文链接：https://www.wllwen.com/kejilunwen/cailiaohuaxuelunwen/2185040.html
