title: A fast and sensitive UHPLC-MS/MS method for the determination of N-butylscopolamine in human plasma: application in a bioequivalence study.
abstract: We have developed and validated a fast and sensitive ultra high-performance liquid chromatography with positive ion electrospray ionization tandem mass spectrometry method for determining N-butylscopolamine levels in human plasma using propranolol as an internal standard. The acquisition was set up in the multiple reaction monitoring mode with the transitions m/z 360.3 → 138.0 for N-butylscopolamine and m/z 260.2 → 116.1 for IS. This method uses a liquid-liquid extraction process with dichloromethane. The analyte and IS were chromatographed on a C18, 50 × 2.1 mm, 1.7 μm column through isocratic elution with acetonitrile-5 mm ammonium acetate (adjusted to pH 3.0 with formic acid). The method was linear in the 1-1000 pg/mL range for N-butylscopolamine and was selective, precise, accurate and robust. The validated method was successfully applied to perform a bioequivalence study of the reference (Buscopan®, from Boehringer Ingelheim) and the test sample coated-tablet formulations (from Foundation for Popular Remedy), both containing 10 mg of N-butylscopolamine bromide administered as a single dose. Using 58 healthy volunteers and accounting for the high intra-individual variability confirmed by statistical calculations (38%), the two formulations were considered bioequivalent because the rate and extent of absorption (within 80-125% interval), satisfying international requirements.
authors.affiliation: Núcleo de Bioequivalência e Ensaios Clínicos, Departmento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Eunice Mayumi
authors.initials: EM
authors.lastname: Suenaga
authors.affiliation: Associação Paulista para o Desenvolvimento da Medicina, São Paulo, SP, Brazil.
authors.forename: Ligia de Cássia
authors.initials: LC
authors.lastname: Val
authors.affiliation: Associação Paulista para o Desenvolvimento da Medicina, São Paulo, SP, Brazil.
authors.forename: Mineko
authors.initials: M
authors.lastname: Tominaga
authors.affiliation: Núcleo de Desenvolvimento Farmacêutico e Cosmético, Universidade Federal de Pernambuco, Recife, PE, Brazil.
authors.forename: José Homero
authors.initials: JH
authors.lastname: Souza Filho
authors.affiliation: Fundação para o Remédio Popular, Secretaria de Saúde do Estado de São Paulo, São Paulo, SP, Brazil.
authors.forename: Gidel
authors.initials: G
authors.lastname: Soares
authors.affiliation: Fundação para o Remédio Popular, Secretaria de Saúde do Estado de São Paulo, São Paulo, SP, Brazil.
authors.forename: Monalisa
authors.initials: M
authors.lastname: Vioto
authors.affiliation: Núcleo de Bioequivalência e Ensaios Clínicos, Departmento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
authors.forename: Clovis Ryuichi
authors.initials: CR
authors.lastname: Nakaie
mesh_terms: D002086:Butylscopolammonium Bromide / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002086:Butylscopolammonium Bromide
keywords: N-butylscopolamine; UHPLC-MS/MS; bioequivalence; human plasma; pharmacokinetic study