title: Quantification of carbamazepine and its active metabolite by direct injection of human milk serum using liquid chromatography tandem ion trap mass spectrometry.
abstract: This work reports the use of a liquid chromatography ion trap tandem mass spectrometry (LC-IT-MS/MS) system for quantification in human milk samples of both carbamazepine (CBZ) and its active metabolite, carbamazepine 10,11-epoxide (CBZE). An octadecyl restricted-access media bovine serum albumin column (RAM-BSA C(18)) was used in single-column mode. Selectivity, extraction efficiency, accuracy and precision were achieved employing 100 μL of the sample, without preparation, with detection limits of 20.0 ng/mL for CBZ and 40.0 ng/mL for CBZE. The matrix effect was investigated for the compounds by post-column infusion (qualitative) and by on-line extraction (quantitative). It was observed suppression effect for CBZ and CBZE by post-column infusion, ion suppression of 0.80 for CBZ, and enhancement of 1.28 for CBZE by on-line extraction. The developed method was validated and applied to analyze breast milk samples from one nursing mother. CBZ and CBZE were quantified in the concentrations of 2.26 μg/mL and 1.54 μg/mL, respectively. To our knowledge, this is the first report on the simultaneous determination of CBZ and its active metabolite by direct injection of human milk serum.
authors.affiliation: Chemistry Department, Federal University of São Carlos, São Carlos, SP, Brazil. bibi_rebelo@yahoo.com.br
authors.forename: B R
authors.initials: BR
authors.lastname: Lopes
authors.forename: J C
authors.initials: JC
authors.lastname: Barreiro
authors.forename: P T
authors.initials: PT
authors.lastname: Baraldi
authors.forename: Q B
authors.initials: QB
authors.lastname: Cass
mesh_terms: D000818:Animals; D002220:Carbamazepine / Q000032:analysis* / Q000378:metabolism; D002417:Cattle; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D004350:Drug Residues; D005260:Female; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D008895:Milk, Human / Q000737:chemistry* / Q000378:metabolism; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D012710:Serum Albumin, Bovine; D002220:Carbamazepine