Simultaneous quantitative analysis of oxcarbazepine and 10,11-dihydro-10-hydroxycarbamazepine in human plasma by liquid chromatography-electrospray tandem mass spectrometry.
A fast and sensitive method to quantify oxcarbazepine (OXC) and its active metabolite, 10,11-dihydro-10-hydroxycarbamazepine (MHD) in human plasma using HPLC-MS/MS has been developed. The method involved liquid-liquid extraction (LLE), with diethyl ether-diclhoromethane (60:40v/v) using deuterade carbamazepine (d10-carbamazepine) as internal standard (IS). The analytes and IS were separated using an isocratic mobile phase (acetonitrile/water (50:50v/v)+20 mM acetic acid) on the analytical column Phenomenex Luna C18 5 microm (150 mm x 4.6 mm) at room temperature. Detection was performed by a Micromass Quatro LC mass spectrometer in the reaction monitoring mode using positive electrospray ionization (ESI+). The MS-MS ion transition monitored were m/z 253>208 for OXC, m/z 255>194 for MHD and m/z 247>204 for IS. Over the range 20-5250 ng/ml for OXC and 40-10,500 ng/ml for MHD, the calibration curves were defined by the following equations: y = 0.00568 + 0.00296x -5.70e - 8x(2) and y = 0.00749 + 0.00178x - 5.70e - 8x(2) for OXC and MHD, respectively. All coefficient of determination (r(2)) were close to unity (0.9986-0.9994). The lower limits of quantification obtained as a result of the LLE procedure was 20 ng/ml for OXC and 40 ng/ml for MHD. The statistical evaluation of the developed method was conducted by examining within-batch and between-batch precision data, which were within the required limits. The suitability of the assay for pharmacokinetics studies was determined by measuring OXC and MHD concentration after administration of a single 10 ml of OXC oral suspension (6%) in plasma human of healthy volunteers.
de Sousa Maia
Maria Bernadete
MB
Department of Physiology and Pharmacology, Federal University of Pernambuco, Av. Prof. Moraes Rêgo S/N, Cidade Universitária, 50670-901 Recife, Pernambuco, Brazil. mbsm@ufpe.br
do Nascimento
Demétrius Fernandes
DF
Martins
Ismael Leite
IL
Cunha
Adriano Nunes
AN
de Lima
Francisco Evanir Gonçalves
FE
Bezerra
Fernando Antônio Frota
FA
de Moraes
Manoel Odorico
MO
de Moraes
Maria Elisabete Amaral
ME
D000927:Anticonvulsants / Q000097:blood* / Q000737:chemistry / Q000378:metabolism*; D002220:Carbamazepine / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D015394:Molecular Structure; D000078330:Oxcarbazepine; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013997:Time Factors
D000927:Anticonvulsants; D002220:Carbamazepine; D000078330:Oxcarbazepine