A simple fluorescence high-performance liquid chromatographic assay for dihydroquinidine in serum.
A simple and rapid reversed-phase C-18 high-performance liquid chromatography (HPLC) assay without a prior extraction step for dihydroquinidine (HQD) in serum is described. The method is selective and useful for monitoring HQD and its presumed metabolites, quinidine (QD), N-oxide QD, 3-hydroxy QD (3-OHQD), and 10-11-diol QD. The detection limit for HQD was 0.2 +/- 0.1 mg/L, and the peak heights--concentration curve was linear between 0.5 and 10.0 mg/L. The coefficients of variation within and between runs were identical, 5.0 +/- 1.5%. A 100 +/- 2.5% recovery was obtained by direct injection into the chromatograph of the supernatant following acetonitrile protein precipitation. The total assay time was less than 15 min.
D001798:Blood Proteins / Q000032:analysis; D011232:Chemical Precipitation; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D011802:Quinidine / Q000031:analogs & derivatives* / Q000097:blood; D013050:Spectrometry, Fluorescence / Q000379:methods
D001798:Blood Proteins; C014486:hydroquinidine; D011802:Quinidine