title: HPLC-UV determination of metformin in human plasma for application in pharmacokinetics and bioequivalence studies.
abstract: In this study, a simple, rapid and sensitive HPLC method with UV detection is described for determination of metformin in plasma samples from bioequivalence assays. Sample preparation was accomplished through protein precipitation with acetonitrile and chromatographic separation was performed on a reversed-phase phenyl column at 40 degrees C. Mobile phase consisted of a mixture of phosphate buffer and acetonitrile at flow rate of 1.0 ml/min. Wavelength was set at 236 nm. The method was applied to a bioequivalence study of two drug products containing metformin, and allowed determination of metformin at low concentrations with a higher throughput than previously described methods.
authors.affiliation: Department of Pharmacy, College of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 580, Bl. 13/15, 05508-900 São Paulo, SP, Brazil. vporta@usp.br
authors.forename: Valentina
authors.initials: V
authors.lastname: Porta
authors.forename: Simone Grigoleto
authors.initials: SG
authors.lastname: Schramm
authors.forename: Eunice Kazue
authors.initials: EK
authors.lastname: Kano
authors.forename: Eunice Emiko
authors.initials: EE
authors.lastname: Koono
authors.forename: Yara Popst
authors.initials: YP
authors.lastname: Armando
authors.forename: Kazuo
authors.initials: K
authors.lastname: Fukuda
authors.forename: Cristina Helena Dos Reis
authors.initials: CH
authors.lastname: Serra
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000284:Administration, Oral; D019540:Area Under Curve; D002138:Calibration; D011232:Chemical Precipitation; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004305:Dose-Response Relationship, Drug; D006207:Half-Life; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D008687:Metformin / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics*; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013810:Therapeutic Equivalency; D013997:Time Factors
chemical_list: D000097:Acetonitriles; D007004:Hypoglycemic Agents; D008687:Metformin