title: Simple spectrophotometric method for determination of melamine in liquid milks based on green Mannich reaction.
abstract: A new and simple spectrophotometric method has been developed and validated for measuring the contamination of melamine in different milk products. The method is based upon measuring the absorption of the complex formed from melamine, 4-hydroxyacetophenone (Hap) and 1-pyrene carboxaldehyde (Pcd), which was adapted from the Mannich reaction. Quantitative analysis was done at a wavelength of 236 nm within a few minutes. The reaction was optimized by focusing on both obtaining high performance of the method and to concern the volatility and toxicity of used reagents. This method provided a linear dynamic range, limit of detection and limit of quantification of 0.100-3.78, 0.08 and 0.14 mg L(-1), respectively. The relative standard deviation (RSD) was 3.6% (n=10). The recoveries of melamine spiked liquid milk samples, with melamine concentrations of 0.63, 1.26, 1.89 and 2.52 mg L(-1), were 87.7±3.7%, 91.1±8.8%, 89.2±4.4% and 90.6±3.6% (n=3), respectively.
authors.affiliation: Division of Science, Faculty of Science and Technology, Rajamangala University of Technology Phra Nakhon (RMUTP), Bangkok 10800, Thailand. woravith.c@rmutp.ac.th
authors.forename: Woravith
authors.initials: W
authors.lastname: Chansuvarn
authors.forename: Sirirat
authors.initials: S
authors.lastname: Panich
authors.forename: Apichat
authors.initials: A
authors.lastname: Imyim
mesh_terms: D000042:Absorption; D000818:Animals; D002138:Calibration; D008352:Mannich Bases / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D009281:Naphthalenes / Q000737:chemistry; D011721:Pyrenes / Q000737:chemistry; D015203:Reproducibility of Results; D013053:Spectrophotometry / Q000379:methods*; D014227:Triazines / Q000032:analysis* / Q000737:chemistry
chemical_list: D008352:Mannich Bases; D009281:Naphthalenes; D011721:Pyrenes; D014227:Triazines; C036464:pyrene-1-aldehyde; C011907:melamine
keywords: 1-Pyrene carboxaldehyde; 4-Hydroxyacetophenone; Liquid milk; Mannich reaction; Melamine; Spectrophotometry