甲烷氧化菌素催化纳米金合成

甲烷氧化菌素(methanobactin,mb)是具有过氧化氢还原酶活性的荧光肽.从甲基弯菌Methylosinus trichospo-rium IMV3011限铜培养介质中分离mb,采用紫外可见全波长扫描法观察mb催化对苯二酚还原氯金酸合成纳米金的作用和影响,当mb/氯金酸/对苯二酚反应液中mb的浓度分别是2.5×10-5mol/L、5.0×10-5mol/L和1.0×10-4mol/L时,形成的纳米金溶液的特征峰分别是561.5 nm(OD561=0.158)、548.0 nm(OD5 48=0.426)、536.5 nm(OD5 36=0.541),特征峰波长减小,对应的吸光值增大,表明mb能够催化对苯二酚还原氯金酸合成纳米金,并且可以通过调控mb的浓度控制纳米金的合成量及粒径大小.

Methanobactin-catalyzed Synthesis of Gold Nanoparticles

Methanobactin(mb) is a fluorescent peptide that appears to function a hydrogen peroxide reductase. mb was found to be accumulated in the spent medium of Methylosinus trichosporium IMV 3011 under copper-limited condition. The role and impact of mb catalysis on the synthesis of gold nanoparticles by hydroquinone reduction of a chloroauric acid (HAuCl4) was observed by the UV–visible absorption spectra. Characteristic peaks of gold nanoparticles was 561.5 nm(OD561=0.158), 548.0 nm(OD548=0.426), 536.5 nm(OD536=0.541) when the mb concentration in mixture was 2.5?0-5 mol/L, 5.0?0-5 mol/L, 1.0?0-4 mol/L, respectively. Wavelength of characteristic peak decreased with increasing absorption value. The results suggested that the synthesis of gold nanoparticles by hydroquinone reduction of a HAuCl4 can be catalyzed by mb, and the synthetic quantity and the size of gold nanoparticles can be controlled by regulating the concentration of mb as well.