银纳米粒子和银离子杀菌机理的红外光谱研究

发布时间：2018-03-20 16:39

  本文选题：银纳米粒子　切入点：银离子　出处：《河北大学》2016年硕士论文　论文类型：学位论文

【摘要】：银作为一种古老的杀菌剂,早在远古时代就被人们所认知和使用。今天,在这个抗生素被滥用的时代,银基杀菌剂以其特有的广谱性和抗耐药性而重新受到人们的青睐。银纳米粒子和银离子是两种常见且具代表性的银基杀菌剂。近年来,人们对这两种杀菌剂在杀菌机理方面的异同产生了极大兴趣,希望通过对这一问题的深入研究为银基杀菌剂的设计和应用提供重要借鉴。在本研究中,我们首次应用红外光谱技术对这两种杀菌剂的杀菌机理在分子水平上进行了对比研究。我们选取常见的大肠杆菌作为模型菌株,采集其被银纳米粒子和银离子作用前后的红外光谱,并在多个重要的红外光谱区域对大肠杆菌受到银杀菌作用前后的结构和组成变化进行了深入细致的谱学分析。这些选取的光谱区域包括对蛋白质错误折叠聚集敏感的酰胺I带振动区(1700-1600 cm~（-1)),对DNA构象变化敏感的磷酸根振动区(1300-1180 cm~（-1)),对自由巯基组成变化敏感的巯基振动区(2580-2530 cm~（-1)),对生物膜结构变化敏感的碳氢链振动区(3000-2820 cm~（-1))和脂多糖糖环振动区(1200-900 cm~（-1))。通过对比研究我们发现,银纳米粒子和银离子在杀菌机制上存在整体杀菌机制类似而具体动力学过程不同的特点。就二者整体杀菌机制而言,我们发现银纳米粒子和银离子都通过如下四种方式和大肠杆菌发生作用,即:(1)银和大肠杆菌内的自由巯基发生配位络合;(2)银使大肠杆菌内蛋白质发生错误折叠聚集;(3)银导致大肠杆菌生物膜上的脂多糖发生缺失;(4)银能引起大肠杆菌内的DNA发生构象改变。就二者和大肠杆菌发生作用时的具体动力学过程而言,我们发现,在银和自由巯基配位以及引起脂多糖缺失方面,银纳米粒子和大肠杆菌的作用是一个慢动力学过程,而银离子和大肠杆菌的作用却是一个快动力学过程。对于银纳米粒子和银离子和大肠杆菌作用时呈现出的这种动力学上的差异,我们从银纳米粒子杀菌的粒子效应的角度出发,提出了一种合理的解释。
[Abstract]:Silver as an ancient fungicide, as early as in ancient times is known and used. Today, the abuse of antibiotics in this era, silver bactericide with its unique broad-spectrum resistance and resistance to by people of all ages. The silver nanoparticles and silver ions are two common and representative silver bactericide. In recent years, people have a great interest in the two kinds of fungicides in the sterilization mechanism of the similarities and differences of hope through in-depth study on this issue provides an important reference for the design and application of silver based fungicides. In this study, we first used the sterilization mechanism of infrared spectroscopy of the two kinds of sterilization agent were investigated at the molecular level. We selected common strains of Escherichia coli as a model, the infrared spectrum before and after the acquisition of silver nanoparticles and silver ions, and in a number of important red outside The spectral region of Escherichia coli by silver structure before and after sterilization and changes in the composition of a detailed spectrum analysis. The selected spectral region including the misfolded protein aggregation sensitive amide I band vibration area (1700-1600 cm~ (-1)), the conformational change of DNA sensitive phosphate (1300-1180 cm~ (vibration area -1)), of free sulfhydryl groups composed of thiol sensitive vibration area changes (2580-2530 cm~ (-1)), the hydrocarbon chain vibration area sensitive to biofilm structure changes (3000-2820 cm~ (-1)) and lipopolysaccharide sugar ring vibration area (1200-900 cm~ (-1)). Through the comparative study we found that silver nanoparticles and silver ion sterilization mechanism and specific similar overall dynamic process of different characteristics in the sterilization mechanism. On the whole the two sterilization mechanism, we found that silver nanoparticles and silver ions through the following four ways and Escherichia coli as 鐢，

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