Specific serum quinidine assay by high-performance liquid chromatography.
- 1 November 1977
- journal article
- research article
- Published by Oxford University Press (OUP) in Clinical Chemistry
- Vol. 23 (11) , 2030-2033
- https://doi.org/10.1093/clinchem/23.11.2030
Abstract
The cardioactive drug quinidine has a narrow therapeutic index; consequently, determination of serum quinidine concentrations can be important. We describe a relatively rapid and specific assay for quinidine in serum by high-performance liquid chromatography. It is suitable for use in patient monitoring or pharmacodynamic studies. Alkalinized serum is extracted with benzene, which is evaporated under nitrogen and reconstituted with methanol; an aliquot is chromatographed. Quinidine is separated from its metabolites and dihydroquinidine (a contaminant in quinidine raw materials). The retention time for quinidine is 4 min 10 s, for dihydroquinidine it is 5.5 min. Results for patients' sera by this assay method and the double-extraction method of Cramer and Isaksson [Scand. J. Clin. Lab. Invest. 15, 553 (1963] correlate well (r = .975).This publication has 2 references indexed in Scilit:
- Serum quinidine concentrations: comparison of fluorescence, gas-chromatographic, and gas-chromatographic/mass-spectrometric methods.Clinical Chemistry, 1976
- Quantitative Determination of Quinidine in PlasmaScandinavian Journal of Clinical and Laboratory Investigation, 1963