title: Determination of melamine and its analogues in egg by gas chromatography-tandem mass spectrometry using an isotope dilution technique.
abstract: A method was developed for the simultaneous determination of melamine, ammeline, ammelide, and cyanuric acid in egg using gas chromatography-tandem mass spectrometry (GC-MS/MS). The samples were first extracted by the solution of diethylamine-water-acetonitrile (10:40:50, v/v/v). Clean-up employed an 'On Guard II' RP cartridge, and the dried elute was derivatised using bis-(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS). Derivatised samples were analysed by GC-MS/MS using multiple-reaction monitoring (MRM) with (13)C(3)-(15)N(3)-labelled melamine and cyanuric acid as internal standards. Blank samples of egg were spiked with the four analytes at concentration level of 0.1, 0.5, 1.0 mg kg(-1), and the intra-day and inter-day recoveries were in the range 75.7-122.5% with the relative standard deviation (RSD) from 2.6% to 22.8%. Decision limits (CCα, α = 0.01) for melamine, ammeline, ammelide, and cyanuric acid in egg samples and milk powder were 3.5-5.9 and 2.5 to 3.8 µg kg(-1), and the detection capabilities (CCβ, β = 0.05) were 4.9-8.4 and 3.6-9.5 µg kg(-1), respectively. The method was successfully applied to egg samples and milk products as well. Satisfactory results were obtained as part of the 2009 European Union melamine proficiency test.
authors.affiliation: Institute of Nutrition and Food Safety, Chinese Centre for Disease Control and Prevention, Beijing 100050, P.R. China.
authors.forename: H
authors.initials: H
authors.lastname: Miao
authors.forename: S
authors.initials: S
authors.lastname: Fan
authors.forename: P P
authors.initials: PP
authors.lastname: Zhou
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: Y F
authors.initials: YF
authors.lastname: Zhao
authors.forename: Y N
authors.initials: YN
authors.lastname: Wu
mesh_terms: D053000:Analytic Sample Preparation Methods; D000818:Animals; D002138:Calibration; D002645:Chickens; D003611:Dairy Products / Q000032:analysis; D004531:Eggs / Q000032:analysis*; D005506:Food Contamination; D005513:Food Inspection / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D007202:Indicators and Reagents / Q000737:chemistry; D057230:Limit of Detection; D011865:Radioisotope Dilution Technique; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry; D014227:Triazines / Q000008:administration & dosage / Q000032:analysis* / Q000737:chemistry; D014297:Trimethylsilyl Compounds / Q000737:chemistry
chemical_list: D007202:Indicators and Reagents; D014227:Triazines; D014297:Trimethylsilyl Compounds; C047270:N,N-bis(trimethylsilyl)-2,2,2-trifluoroacetamide; C039293:trimethylchlorosilane; C004632:cyanuric acid; C067139:ammelide; C000089:ammeline; C011907:melamine