Km. Matar et al., A RAPID LIQUID-CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF LAMOTRIGINE IN PLASMA, Journal of pharmaceutical and biomedical analysis, 17(3), 1998, pp. 525-531
A rapid,sensitive and simple high-performance liquid chromatographic (
HPLC) method for the determination of lamotrigine in plasma is describ
ed. The drug was extracted from 100 mu l of plasma with chloroform: is
opropanol (95:5% v/v) in the presence of 100 mu l of phosphate buffer
(10 mM). The extract was evaporated and the residue was reconstituted
with mobile phase and injected onto the HPLC system. The drug and the
internal standard (chloramphenicol) were eluted from a Symmetry C-18 s
tainless steel column at ambient temperature with a mobile phase consi
sting of 0.01 M potassium phosphate-acetonitrile-methanol (70:20:10% v
/v/v), adjusted to pH 6.7, at a flow rate of 1.3 ml min(-1) and the de
tector was monitored at 214 nm. Quantitation was achieved by measureme
nt of the peak-area ratio of the drug to the internal standard and the
lower limit of detection for lamotrigine in plasma was 20 ng ml(-1).
The intraday precision ranged from 3.34 to 6.12% coefficient of variat
ion (CV) and the interday precision ranged from 2.15 to 8.34% CV. The
absolute and relative recoveries of lamotrigine ranged from 86.93 to 9
0.71% and from 95.18 to 107.13%, respectively. The method was applied
in studying the pharmacokinetics of lamotrigine administered orally to
rabbits. This reliable micro-method would have application in pharmac
okinetic studies of lamotrigine where only small sample sizes are avai
lable, e.g. paediatric patients. (C) 1998 Elsevier Science B.V. All ri
ghts reserved.