Voltammetric determination of the antimalarial drug hydroxychloroquine in synthetic urine sample

Abstract

The present investigation reports a rapid electrochemical determination method for an antimalarial drug, hydroxychloroquine (HCQ), using a cationic surfactant. Different solubilized media including surfactants and organic solvents have been screened, and cetyltrimethylammonium bromide (CTAB) has been selected. Electrochemical techniques, namely, Cyclic Voltammetry (CV), Square Wave Voltammetry (SWV), and Differential Pulse Voltammetry (DPV) have been employed to determine the peak current of analyte solution. Adding CTAB to the HCQ solution results in the highest peak current among the studied solubilized systems. The current signal of HCQ observed due to its oxidation is found to be a function of drug concentration, pH of analyte solution and the type of additives. The DPV results are linear over the concentration range of 5-60 μg/mL with a limit of detection at 2.41 μg/mL. Excipients including important organic compounds and amino acids have been used to study their interference in HCQ quantification. The proposed method has been successfully applied to determine HCQ in spiked synthetic urine samples. The results reveal good recovery values in the range of 89-104% for different concentrations of HCQ. Thus, the proposed method shows potential applicability for in vitro determination of the drug in urine samples.