DTT对三苯基甲烷染料脱色的研究

研究了二硫苏糖醇(dithiothreitol,DTT)对三苯基甲烷染料的还原脱色作用.以孔雀石绿为代表,优化了反应体系中DTT的用量,目的是考察孔雀石绿和DTT之间的定量关系,并明确DTT对孔雀石绿的脱色能力.分析了反应体系pH值对DTT还原力的影响.结果表明,在pH值>5的反应体系中,平均每1 mol DTT可在1 min内脱色4 mol孔雀石绿,脱色率高达97%.脱色产物经HPLC分析表明,孔雀石绿被DTT还原脱色为隐色孔雀石绿.隐色孔雀石绿可继续与氧化态的DTT结合成为水不溶性的络合物,形成白色沉淀.DTT对结晶紫、灿烂绿及碱性品红的脱色作用均达到85%以上,以此确定DTT是一类广谱的三苯基甲烷类染料脱色剂.

Study on Decolorization of Triphenylmethane Dyes by DTT

Decolorization of triphenylmethane dyes by DTT was researched. For malachite green, content of DTT in reaction system was optimized to investigate the quantitative relation between DTT and malachite green and the decolorization capacity of DTT was confirmed. Effect of pH of reaction system on reducibility of DTT was explored. The results indicated 4 mol malachite green could be decolorized by 1 mol DTT averagely within 1 min, when pH of the reaction system was above 5.The decolorization rate was up to 97%. Decolorization product of malachite mreen was corroborated to be its leuco form by HPLC analysis. Some insoluble compounds, which could be the complex products of leuco malachite green with DTT, were formed during the decolorization reaction. Decolorization of crystal violet, brilliant green and basic fuchsin by DTT was tested further, and the decolorization rates were all above 85%, which suggested DTT was a broad-spectrum decolorization agent for triphenylmethane dyes.