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对休眠的巨大芽孢杆菌 (Bacillusmegatherium)D0 1菌体吸附Au3 + 的作用过程进行了谱学表征 .运用AAS考察了pH、时间和温度对D0 1菌体吸附Au3 + 过程的化学动力学和热力学相关参数的影响 .D0 1菌粉中硫元素含量的EDX分析说明该菌体中对Au3 + 具有还原作用的L 半胱氨酸和蛋氨酸的含量极少 ;D0 1菌体水解后葡萄糖含量的UV vis测定说明该菌体水解产物中含有一定量的还原糖 .空白的和吸附Au3 + 的D0 1菌体的FTIR检测表明该菌体细胞壁肽聚糖层糖类化合物的羟基和肽链侧链氨基酸残基离子化羧基为吸附Au3 + 的活性基团 ;肽聚糖层部分多糖的水解产物低聚糖、二糖及单糖等还原糖的半缩醛羟基游离态醛基为电子供体 ,将Au3 + 原位还原成Au0 .葡萄糖和Au3 + 相互作用的XRD和FTIR表征证明Au3 + 是在还原糖的醛基上直接被还原成Au0
The process of adsorption of Au3 + by dormant Bacillus megaterium D0 1 was characterized by spectroscopy. The effects of pH, time and temperature on the kinetics and thermodynamics of Au3 + adsorption on D0 1 cells were investigated by AAS The EDX analysis of sulfur content in D0 1 bacterial powder showed that the content of L-cysteine and methionine with reducing effect on Au3 + was very little in this strain. The UV vis of glucose content after hydrolysis of D0 1 strain The results showed that the hydrolyzate of this strain contained a certain amount of reducing sugar.The FTIR results of blank and adsorbed Au3 + D0 1 strain showed that the hydroxyl and peptide side chain residues of the cell wall peptidoglycan carbohydrate Base ionized carboxyl groups are the active groups adsorbing Au3 +; peptidoglycan layer partial polysaccharide hydrolyzate oligosaccharides, disaccharides and monosaccharides and other reducing sugars hemiacetal hydroxyl free aldehyde groups as electron donors, the Au3 + Situ reduction to Au 0. The XRD and FTIR characterization of the interaction between glucose and Au3 + demonstrate that Au3 + is directly reduced to Au0 on the aldehyde of reducing sugar