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利用生物及其提取物合成纳米金具有反应条件温和、环境友好等优点.以菌株Trichosporon montevideense WIN提取物合成纳米金(Au NPs),考察反应时间、p H和提取物浓度对纳米金合成的影响,并探讨纳米金催化还原硝基芳烃的特性.结果显示,纳米金合成过程可在7 d内稳定,最优p H为7.0,最适提取物浓度为300 mg/L.通过紫外-可见光谱扫描、透射电子显微镜和傅立叶转换红外线光谱分析可知,纳米金为球形和伪球形,尺寸分布范围为4-35 nm,平均粒径为(18.2±0.4)nm,推测提取物中的羟基、氨基和羧基参与了纳米金的还原和稳定过程.纳米金对2-硝基苯酚、3-硝基苯酚、4-硝基苯酚、2-硝基苯胺和3-硝基苯胺具有良好的催化活性,其催化反应速率常数分别为7.5×10~(-3)s~(-1)、6.4×10~(-3) s~(-1)、9.1×10~(-3) s~(-1)、11.8×10~(-3) s~(-1)和20.7×10~(-3) s~(-1).本研究表明T.montevideense WIN在生物合成纳米金方面具有潜在的应用价值,且合成的生物纳米金能够有效应用于硝基芳烃污染物的催化还原.
The biosynthesis of gold nanoparticles by using biological and its extracts has the advantages of mild reaction conditions, environment friendly, etc. Au NPs were synthesized by the strain Trichosporon montevideense WIN and the effect of reaction time, p H and extract concentration on the synthesis of gold nanoparticles , And discussed the properties of nano-gold catalyzed reduction of nitroaromatics. The results showed that the synthesis of nano-gold can be stabilized within 7 days, the optimal p H was 7.0, the optimum concentration of extract was 300 mg / L. Through UV-Vis Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy showed that the gold nanoparticles were spherical and pseudospherical with a size distribution of 4-35 nm and an average diameter of (18.2 ± 0.4) nm. Carboxyl groups participate in the reduction and stabilization of gold nanoparticles. Gold nanoparticles have good catalytic activity for 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitroaniline and 3-nitroaniline. The catalytic reaction rate constants were 7.5 × 10 -3 s -1, 6.4 × 10 -3 s -1, 9.1 × 10 -3 s -1, , 11.8 × 10 ~ (-3) s ~ (-1) and 20.7 × 10 ~ (-3) s ~ (-1), respectively.This study shows that T.montevideense WIN is a biosynthetic gold nanoparticle Potential applications, and biological synthesis of gold nanoparticles can be effectively applied to the catalytic reduction of nitroaromatic pollutants.