Chloroquine assay

Fig. (3). Hemozoin Production Mediated by Bionucleating Templates. Representative polymerization assay with 50 pM of hemin in 2 ml acetate buffer (500 mM, pH 4.8) at 37° C. BNTI and BNTII were used in 1 and 2 nmol amounts. Chloroquine (CQ, 100 pM) was included with BNT I and BNT n in inhibition reactions. Polyhistidine and bovine serum albumin in approximately 1 and 2 nmol amounts were used in protein control experiments. The blank control was the acetate buffer above. Base line amounts of insoluble aggregate are consistent with those previously reported under similar conditions.

A rapid semiautomated microdilution method for the microbiological assay of the chloroquine has been developed by Desgardins (26). Antimalarial activity of chloroquine may be studied against cultured Plasmodium falciparum, microplates are used to prepare serial dilution of the drug. Parasites obtained from continuous stock cultures are subcultured in the micro-plates for 42 h. Inhibition of uptake of a radio labeled nucleic acid precursor by parasites serves as the indicator of antimicrobial activity. 

Chloroquine has been assayed spectro-photometrically (27) using the APj method (28) that depends on differences in orthogonal function coefficients. 

Novartis Malaria Data from Gamo et al. (14), P. falciparum strains 3d7 (drug-susceptible), and W2 (chloroquine-, quinine-, pyrimethamine-, cycloguanil-, and sulfadoxine-resistant), obtained from MR4, were tested in an erythrocyte-based infection assay for susceptibility to inhibition of proliferation by selected compounds. 5,695... 

In parallel, extensive studies on P. falciparum field isolates in Gabon [140-142], Senegal [143], Cambodia [118, 119, 144], and the Thailand Burmese border [145] corroborated the efficacy of FQ on the parasite whatever its resistance level to chloroquine or to other commonly used antimalarials mefloquine, quinine, halofantrine, and artemisinin derivatives [146, 147]. The cross reactivity observed in some studies with CQ was limited and it was demonstrated that it was caused by differences in initial parasitemia among isolates at the start of the assays [141]. Independance of susceptibility of P. falciparum with phenotypic variation of pfcrt gene, responsible for CQ resistance, could be suspected from these results, but this was demonstrated at the molecular level on Cambodia isolates [148] and extended further on other genes currently involved in resistance to aminoquinoline antimalarials [89, 90]. 

C Escande, et al. Sensitive radioimmunoassay and enzyme linked immunosorbent assay for the simultaneous determination of chloroquine and its metabolites in biological fluids. J Pharm Sci 79 23, 1990. 

Hays, P.A. Lurie, l.S. Quantitative analysis of adulterants in illicit heroin samples via reversed phase HPLC. J.Liq.Chromatogr., 1991, 14, 3513—3517 [simultaneous acetaminophen, acetylcodeine, ace-tylmorphine, benzocaine, caffeine, chloroquine, diamorphine, diazepam, diphenhydramine, dipyrone, lidocaine, methaqualone, monoacetylmorphine, morphine, nicotinamide, noscapine, papaverine, phe-nacetin, phenobarbital, phenolphthalein, N-phenyl-2-naphthylamine, salicylic acid, strychnine] Shen, J. Wanwimolruk, S. Clark, C.R. Roberts, M.S. A sensitive assay for aspirin and its metabolites using reversed-phase ion-pair high-performance liquid chromatography. J.Liq.Chromatogr., 1990,13, 751-761 [simultaneous metabolites gentisic acid, salicyluric acid LOD 50 ng/mL]... 

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