HPLC quantification of metoprolol with solid-phase extraction for the drug monitoring of pediatric patients.
Although the analytical literature seems abundant for the determination of metoprolol in human plasma, a method using standard equipment providing a sensitive and simple high-performance liquid chromatographic (HPLC) method for limited blood volume, e.g. where 1 mL of blood in a 1 kg infant equals 70 mL of adult blood volume, has rarely been addressed. Therefore, in 500 microL of plasma, metoprolol was extracted using an internal standard and solid-phase extraction columns. Chromatographic analysis was performed on a Spherisorb C(6) column (5 microm particle size) at ambient temperature and fluorimetric detection with an excitation wavelength of 225 nm, and emission wavelength of 310 nm. The mobile phase [30% acetonitrile and 70% 0.25 m potassium acetate buffer (pH 4)] was pumped with 1 mL/min. Metoprolol recovery was determined at 73.0 +/- 20.5%, and the limit of quantitation was 2.4 ng/mL. Precision values of intra- and inter-assay were below 15.5% and those for accuracy were between 90 and 110%. This method was developed for monitoring and determination of pharmacokinetic parameters of metoprolol in pediatric patients and therefore metoprolol plasma concentrations in a 2-year-old child with ventricular tachycardia are reported. .
Institut für Experimentelle und Klinische Pharmakologie, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Stefanie
S
Albers
Jan-Peer
JP
Elshoff
Christina
C
Völker
Andrea
A
Richter
Stephanie
S
Läer
D000328:Adult; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D016903:Drug Monitoring / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008790:Metoprolol / Q000097:blood* / Q000627:therapeutic use; D012680:Sensitivity and Specificity; D017180:Tachycardia, Ventricular / Q000188:drug therapy
D008790:Metoprolol