A strategy for rapid and facile detection of melamine in food and other substances is described. Unmodified gold nanoparticles enable a colorimetric signal output that is amplified through integration by precipitation formation via a chemical component specific to melamine. The sensitivity was determined to be ∼ 40 ppb with a two standard deviation cutoff.
University of Miami机械与航空工程系助理教授Na Li和她的同事开发出一种快速而廉价的检验乳制品中是否含三聚氰胺的新方法。三聚氰胺是2007和2008年中国生产的毒宠物食品和毒牛奶中的污染物。毒奶使数千人致病,并引起全球范围内召回中国乳制品。 这种检测法首先分离乳品中干扰检测的酪蛋白,然后加入纳米金。纳米金和三聚氰胺相互作用,使得溶液在数秒钟内由红变蓝。之后加入三聚氰酸,三聚氰酸和三聚氰胺作用产生沉淀,以加强特征辨识。两种反应通过肉眼和分光光度测定法均可观察到。