title: A micro-modification for quantification of chloroquine in whole blood by fluorimetric assay.
abstract: The use of whole blood in fluorimetric assays for chloroquine is discussed. Since whole blood contains a much higher concentration of chloroquine than plasma (Fitch, 1969), such use allows for a longer period of sampling following a single oral dose of chloroquine. Chloroquine can be reproducibly quantified (coefficient of variation: 5%) from samples collected for up to 4-6 weeks after a single oral dose. This prolonged sampling provides for a more complete characterization of the true terminal slope of the chloroquine concentration-time curve. The usual fluorimetric methods of assay (Brodie et al., 1947; McChesney, Banks & McAuliff, 1962; Schulman & Young, 1974; Vogel & Konigk, 1975) do not differentiate very accurately concentrations of chloroquine below 50 ng/ml (coefficient of variation 20%). This micro-modification enables the determination of chloroquine concentrations below 50 ng/ml with a degree of accuracy much better (coefficient of variation 5%) than that of the usual fluorimetric methods.
mesh_terms: D002738:Chloroquine / Q000097:blood*; D005470:Fluorometry / Q000379:methods; D006801:Humans; D008832:Microchemistry
chemical_list: D002738:Chloroquine