Analytical Methodologies for Determination of Hydroxychloroquine and Its Metabolites in Pharmaceutical, Biological and Environmental Samples

Background: Hydroxychloroquine (HCQ) was initially launched as an antimalarial drug, but now it is also used as a slow-acting anti-rheumatic drug. It contains equal proportions of (-)-(R)-hydroxychloroquine and (+)-(S)-hydroxychloroquine. Introduction: Hydroxychloroquine, a synthetic 4-aminoquinoline derivative, possesses antimalarial, antirheumatic activity and also exerts beneficial effects on lupus erythematous disease. Substantial levels of three metabolites of HCQ, which are desethylchloroquine (DCQ), bisdesethylhydroxychloroquine (BDCQ), and desethylhydroxychloroquine (DHCQ), have been determined by various analytical techniques from blood and plasma. Methods: Various analytical techniques have been reported for asynchronous and simultaneous estimation of HCQ and their metabolites in pharmaceuticals and biological samples like serum, whole blood, and urine. The analytical techniques are Square-wave voltammetry employed with the cathodically pretreated boron-doped diamond electrode, fast UHPLC–fluorescent method, UV spectrophotometry, UHPLC-UV analysis, RP-HPLC, mass spectrometry, NMR, and CE. Results and discussion: We have complied with various analytical methods for detection of HCQ with its various metabolites simultaneous or alone in pharmaceutical dosage forms, biological and environmental samples. The authors believe that the above-mentioned studies compiled in this report will give a choice to readers to select the most appropriate and suitable method for the analysis of HCQ. Further, it is also believed that this study will help the researchers to develop a more sensitive, convenient, and rapid method based on literature reports.