title: Visual detection of melamine in milk products by label-free gold nanoparticles.
abstract: A simple, rapid, field-portable colorimetric method for the detection of melamine based on melamine-induced color change of label-free gold nanoparticles (Au NPs) was developed in this study. Melamine can induced the aggregation of Au NPs and results in the color change from wine-red to purple, which provided a platform for rapid and field-portable colorimetric detection of melamine. The proposed method can be used to detect melamine in liquid milk and infant formula with a detection limit of 1.0 and 4.2ppm, respectively, within 30min by naked eyes observation without the aid of any advanced instrument and the need of any complex pretreatment, and detect as low as 0.15ppm of melamine in liquid milk and 2.5ppm of melamine in infant formula with UV-vis-spectroscopy. The proposed method is promising for on-site screening of melamine adulterant in milk products.
authors.affiliation: Ministry of Education Key Laboratory of Analysis and Detection for Food Safety (Fuzhou University), Fuzhou, Fujian 350108, China. lqguo@fzu.edu.cn
authors.forename: Liangqia
authors.initials: L
authors.lastname: Guo
authors.forename: Jianhai
authors.initials: J
authors.lastname: Zhong
authors.forename: Jinmei
authors.initials: J
authors.lastname: Wu
authors.forename: Fengfu
authors.initials: F
authors.lastname: Fu
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zheng
authors.forename: Song
authors.initials: S
authors.lastname: Lin
mesh_terms: D000818:Animals; D002725:Chloroform / Q000737:chemistry; D003124:Colorimetry / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007202:Indicators and Reagents / Q000737:chemistry; D007223:Infant; D041943:Infant Formula / Q000737:chemistry*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D013997:Time Factors; D014227:Triazines / Q000032:analysis*; D014238:Trichloroacetic Acid / Q000737:chemistry
chemical_list: D007202:Indicators and Reagents; D014227:Triazines; D014238:Trichloroacetic Acid; D006046:Gold; D002725:Chloroform; C011907:melamine