title: Development of gold nanoparticle-based rapid detection kit for melamine in milk products.
abstract: A reliable and sensitive kit for the rapid detection of melamine (Mel) was developed. The kit is based on gold nanoparticle (Au NP) probe and includes a standard colorimetric card. The Au NPs were prepared by sodium borohydride reduction and characterized by transmission electron microscopy, which revealed particle sizes of approximately 5 nm. The performance of the kit in terms of aggregation kinetics, cross-reactivity, anti-interference, and sample pretreatment was investigated. The standard colorimetric card was then fabricated by chromatic aberration of a series of standard Mel-spiked milk reacts with the 5 nm Au NPs. The working range of the kit is 1-120 mg/L, and its performance is visibly more rapid and reliable by comparison with the standard colorimetric card. As low as 1 mg/L of Mel levels in milk can be determined, with the assay taking only about 10 min, including sample pretreatment. The kit can be stored for a year at room temperature. Samples were also detected by the kit, yielding results close to those obtained by high-performance liquid chromatography/mass spectrometry. Thus, the kit is applicable to qualitative and semiquantitative field detection, as well as naked-eye screening without the aid of any instrumentation.
authors.affiliation: Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Health and Environmental Medicine, Tianjin 300050, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Nan
authors.initials: N
authors.lastname: Liu
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Qie
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Baoan
authors.initials: B
authors.lastname: Ning
authors.forename: Zhixian
authors.initials: Z
authors.lastname: Gao
mesh_terms: D000327:Adsorption; D000818:Animals; D002417:Cattle; D005506:Food Contamination / Q000032:analysis*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D011933:Reagent Kits, Diagnostic; D014227:Triazines / Q000032:analysis*
chemical_list: D011933:Reagent Kits, Diagnostic; D014227:Triazines; D006046:Gold; C011907:melamine