Simultaneous determination of zonisamide, carbamazepine and carbamazepine-10,11-epoxide in infant serum by high-performance liquid chromatography.
This study developed a simple method for the simultaneous determination of zonisamide (ZNS), carbamazepine (CBZ) and its active metabolite, carbamazepine-10,11-epoxide (CBZE) in infant serum using reversed-phase high-performance liquid chromatograph (HPLC). The method involves a single-step protein precipitation procedure that uses no solid-phase or liquid-liquid extraction. The HPLC separation was carried out on a Cadenza CD-C18 column (3 microm, 4.6 mm x 150 mm) with potassium phosphate buffer (pH 4.6; 25 mM)-methanol-acetonitrile (65:20:15 (v/v/v)) as a mobile phase at a 1.0 ml/min flow rate: ZNS was detectable using a UV detector at 235 nm, and both CBZ and CBZE were at 215 nm. The quantification limits were established in accordance with each therapeutic range at 2.5 microg/ml for ZNS, 0.5 microg/ml for CBZ, and 0.25 microg/ml for CBZE. The respective coefficients of variation were 1.3-6.0% and 2.2-7.7% for the intra- and inter-assay.
Yoshida
Terumitsu
T
Division of Clinical Research, Saitama Prefectural Institute of Children's Medical Center, 2100 Magome, Iwatsuki-ku, Saitama-shi, Saitama 339-8551, Japan. a0183776@pref.saitama.lg.jp
Imai
Koichi
K
Motohashi
Sumiko
S
Hamano
Shin-ichiro
S
Sato
Masato
M
D000927:Anticonvulsants / Q000097:blood* / Q000627:therapeutic use; D002220:Carbamazepine / Q000031:analogs & derivatives* / Q000097:blood* / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004827:Epilepsy / Q000097:blood / Q000188:drug therapy; D006801:Humans; D007223:Infant; D007555:Isoxazoles / Q000097:blood* / Q000627:therapeutic use; D000078305:Zonisamide
D000927:Anticonvulsants; D007555:Isoxazoles; D002220:Carbamazepine; D000078305:Zonisamide; C012227:carbamazepine epoxide