2-硫代巴比妥酸修饰金纳米探针高灵敏比色检测三聚氰胺

以2-硫代巴比妥酸(TBA)修饰金纳米粒子为探针，TBA与三聚氰胺通过氢键作用诱导金纳米探针团聚，进而使金纳米胶体颜色由酒红色变为蓝色。 实验优化得最佳反应条件为在乙酸缓冲溶液（pH=7.0）介质中，室温反应15 min。 对不同浓度三聚氰胺进行检测时发现，在0.062~0.18 μmol/L和0.18~6.0 μmol/L之间，A660/A520吸收比率与三聚氰胺浓度呈现良好的线性关系，检出限为0.043 μmol/L。 该方法用于检测牛奶样品中的三聚氰胺的加标回收率为102.8%～105.3%。

Using 2-Thiobarbituric Acid-modified Gold Nanoparticles as Colorimetric Probes for Sensitive Detection of Melamine

A simple and rapid colorimetric method was developed for the detection of melamine using 2-thiobarbituric acid-modified gold nanoparticles(TBA-AuNPs) as probes. Melamine can induce the aggregation of TBA-AuNPs via the hydrogen-bonding interactions in acetic acid buffer solutions(pH=7), resulting in the color change from wine-red to blue within 15 min at room temperature. Under optimized conditions, the absorption ratio of the A660/A520 shows good linear relationship with the melamine concentration in the range of 0.062~0.18 μmol/L and 0.18~6.0 μmol/L, respectively, with the detection limit of 0.043 μmol/L. The recoveries of the method are within the range of 102.8%～105.3%. It provides a platform for rapid, selective and sensitive colorimetric detection of melamine in milk samples.