title: Hydrogen-bonding recognition-induced aggregation of gold nanoparticles for the determination of the migration of melamine monomers using dynamic light scattering.
abstract: The migration of melamine monomers from food contact materials has aroused particular attention since the 2008 melamine-tainted milk scandal in China. However, the determination of melamine monomer's migratory quantity (MMMQ) has remained an open question because of the complex sample pretreatment and the low sensitivity. Based on the hydrogen bonding interaction between DNA thymine and melamine, this paper described a simple and rapid method focusing on the measurement of MMMQ from melamine tableware by gold nanoparticles (GNPs) and dynamic light scattering (DLS). With the presence of probe DNA (p-DNA), the GNPs were stable in NaCl solution (0.06 M), whereas they became aggregated when the p-DNA hybridized with melamine. The change in the hydrodynamic diameter of GNPs could be detected by DLS technology. Under the optimal conditions, the average diameter increased linearly with the concentration of melamine over the range from 5.0 to 320.0 μg L(-1), and showed a detection limit of 2.0 μg L(-1) (3σ/slope). The MMMQ was investigated within a range from 6.00×10(-4) to 2.58×10(-1) mg dm(-2) (n≥3) in four different food simulants at different temperatures and time points. The results suggest that the DLS method has great potential in the analysis of the migration of melamine monomers.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Long
authors.initials: L
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Zhicheng
authors.initials: Z
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Kang
authors.initials: K
authors.lastname: Shao
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Feng
authors.initials: F
authors.lastname: Shao
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Science, Huazhong Agricultural University, Wuhan 430070, PR China. Electronic address: hyhan@mail.hzau.edu.cn.
authors.forename: Heyou
authors.initials: H
authors.lastname: Han
mesh_terms: D004247:DNA / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006860:Hydrogen Bonding; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D015394:Molecular Structure; D012542:Scattering, Radiation; D014227:Triazines / Q000032:analysis* / Q000737:chemistry
chemical_list: D014227:Triazines; D006046:Gold; D004247:DNA; C011907:melamine
keywords: Dynamic light scattering; Gold nanoparticles; Melamine tableware; Migration of melamine monomers; Oligonucleotides