title: Development of aqueous mobile phase using chaotrope for the chromatographic determination of melamine in infant formula.
abstract: Direct analysis of melamine using reverse phase chromatography is a challenge because this compound's small size and strong polar nature leads to abnormal peak symmetry as well as poor retention. Here, we introduce a simple and reliable reverse phase liquid chromatographic method using sodium hexafluorophosphate to modify an acidic aqueous eluent, resulting in improved chromatographic behaviors of melamine in complex food matrices. Variables affecting the retention mechanism, including chaotrope type, concentration and stationary phase, were investigated. Under optimum conditions, melamine retention, separation efficiency, peak shape and reproducibility were significantly improved as compared to other methods that use ionic liquids or a micellar mobile phase. No interference affected melamine detection when infant formula was applied as the food matrix. Analytical reliability was demonstrated through estimation of validation parameters such as specificity, linearity, precision, accuracy and recovery. This method is suitable for routine analysis of melamine in infant formula. More noteworthy, this is the first time that an organic solvent-free mobile phase using chaotropic salt, meeting the concept of green chemistry, has been proposed.
authors.affiliation: Department of Food Science and Human Nutrition, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA.
authors.forename: Joon Hyuk
authors.initials: JH
authors.lastname: Suh
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Juhee
authors.initials: J
authors.lastname: Jung
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Byeonghee
authors.initials: B
authors.lastname: Kim
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Hyun-Deok
authors.initials: HD
authors.lastname: Cho
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Junghyun
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Taeyong
authors.initials: T
authors.lastname: Eom
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea.
authors.forename: Mihee
authors.initials: M
authors.lastname: Park
authors.affiliation: Department of Food Science and Human Nutrition, Citrus Research and Education Center, University of Florida, 700 Experiment Station Rd, Lake Alfred, FL 33850, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Pharmaceutical Analysis, College of Pharmacy, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea. Electronic address: hansb@cau.ac.kr.
authors.forename: Sang Beom
authors.initials: SB
authors.lastname: Han
mesh_terms: D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D005504:Food Analysis; D055772:Green Chemistry Technology; D006801:Humans; D007223:Infant; D041943:Infant Formula / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry; D008823:Micelles; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D014227:Triazines / Q000032:analysis*
chemical_list: D052578:Ionic Liquids; D008823:Micelles; D012997:Solvents; D014227:Triazines; C011907:melamine
keywords: Aqueous mobile phase; Chaotrope; Chromatography; Green chemistry; Infant formula; Melamine