title: Pulsed electromembrane extraction for analysis of derivatized amino acids: A powerful technique for determination of animal source of gelatin samples.
abstract: Differentiation of animal sources of gelatin is required for many reasons such as some anxieties about bovine spongiform encephalopathy or a ban on consuming porcine gelatin in some religions. In the present work, an efficient method is introduced for determination of animal origin of gelatin samples. The basis of this procedure is the application of pulsed electric field for extraction, preconcentration, and analysis of derivatized amino acids in gelatin. To this end, after derivatization of amino acids of interest by means of o-phthalaldehyde (OPA) for enhancing their ultraviolet (UV) absorbance as well as increasing their lipophilicities, a 137V electric field was applied for 20min with 10min(-1) frequency to make the analytes migrate through a 200µm organic liquid membrane into an aqueous acceptor phase. Finally, the acceptor phase was analyzed by HPLC-UV. The proposed technique offered a high efficiency for analysis of amino acids, regarding 43% and 79% as extraction recoveries and 25ng mL(-1) and 50ng mL(-1) as limits of detection (LODs) for asparagine and glutamine, respectively. Therefore, due to sample cleanup ability of the proposed method and obtained preconcentration factors (29 and 53 for asparagine and glutamine, respectively), it could be carried out for differentiation of animal origins of gelatin samples, even if only small amounts of samples are available or in complicated media of foodstuffs and medicament.
authors.affiliation: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Rezazadeh
authors.affiliation: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran. Electronic address: yyamini@modares.ac.ir.
authors.forename: Yadollah
authors.initials: Y
authors.lastname: Yamini
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, Tehran, Iran.
authors.forename: Shahram
authors.initials: S
authors.lastname: Seidi
authors.affiliation: Faravari Darooi Gelatin Halal Company, Alborz Industrial City, Qazvin, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Aghaei
mesh_terms: D000818:Animals; D001216:Asparagine / Q000032:analysis*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005780:Gelatin / Q000737:chemistry*; D005973:Glutamine / Q000032:analysis*; D013552:Swine; D009764:o-Phthalaldehyde / Q000737:chemistry
chemical_list: D005973:Glutamine; D009764:o-Phthalaldehyde; D001216:Asparagine; D005780:Gelatin
keywords: Amino acids; Bovine; Gelatin; Porcine; Pulsed electromembrane extraction; o-phthalaldehyde derivatization