Determination of Lamotrigine Simultaneously with Carbamazepine, Carbamazepine Epoxide, Phenytoin, Phenobarbital, and Primidone in Human Plasma by SPME-GC-TSD

• Published in: Journal of chromatographic science Vol. 40; no. 4; pp. 219 - 223
• Main Authors: Queiroz, M.E.C., Silva, S.M., Carvalho, D., Lanças, F.M.
• Format: Journal Article
• Language: English
• Published: Niles, IL Oxford University Press 01-04-2002; Preston Publications
• Subjects: Analysis; Anticonvulsants - blood; Biological and medical sciences; Carbamazepine - blood; Chromatography, Gas - methods; General pharmacology; Humans; Lamotrigine; Medical sciences; Pharmacology. Drug treatments; Phenobarbital - blood; Phenytoin - blood; Primidone - blood; Triazines - blood; Biological fluid; Chemical analysis; Epilepsy; Anticonvulsant; Blood; Blood plasma; Sample preparation; Mood stabilizer; Sedative; Barbiturates; Quantitative analysis; Human; Validation; Nervous system diseases; Primidone; Routine analysis; Tricyclic compound; Normal; Hydantoins; Carbamazepine; Cerebral disorder; Solid phase microextraction; Gas chromatography; Phenobarbital; Central nervous system disease; Simultaneous measurement; Pyrimidine derivatives; Thermoionic detector; Dibenzazepine derivatives; Phenytoin
• ISSN: 0021-9665; 1945-239X
• DOI: 10.1093/chromsci/40.4.219

A simple and rapid analytical method is presented for the determination of lamotrigine simultaneously with primidone, carbamazepine, carbamazepine epoxide, phenobarbital, and phenytoin in human plasma using solid-phase microextraction (SPME) and gas chromatography with thermionic specific detection. The best conditions for the SPME procedure is established as following: direct extraction on a 65-µm Carbowax-divinylbenzene fiber; 1.0 mL of a sample plasma matrix modified with 15% NaCl and 3 mL of a potassium phosphate buffer (pH 7.0); extraction temperature at 30°C; and stirring at a rate of 2500 rpm for 15 min. The method shows good linearity between 0.05 and 40.0 µg/mL with regression coefficients ranging between 0.9965 and 0.9995 and a coefficient of variation of the points of the calibration curve lower than 10%. The lowest limit of quantitation for the plasma-investigated drugs varies from 0.05 to 0.20 µg/mL, according to the drug. The proposed method is sensitive enough to work into subtherapeutic and therapeutic concentrations, being that it is applied in pharmacokinetic studies and patient routine therapeutic drug monitoring.