Electrochemical Determination of Chloroquine Phosphate in Real Samples Using a Diresorcinate‐1,10‐phenanthrolinecobalt(II)‐Modified Glassy Carbon Electrode

Chloroquine phosphate (CQP) is used for malaria treatment. As it is facing increasing resistance, it needs continuous monitoring using sensitive and specific detection methods. In this work, a voltammetric sensor was prepared by electropolymerization of a diresorcinate‐1,10‐phenanthrolinecobalt(II) complex on a glassy carbon electrode (poly(DHRPCo)/GCE) which was followingly characterized. Compared with a bare GCE, CQP showed single well shaped irreversible oxidative peak at the poly(DHRPCo)/GCE. The peak current showed excellent linearity with CQP concentration in the range of 0.005–300.0 μm with a detection limit of 0.39 nm. The response of CQP at poly(DHRPCo)/GCE was not influenced by the presence of amoxicillin, ciprofloxacillin and paracetamol in addition to its high stability and reproducibility. It was applied for detection of CQP in various real samples, including three brands of tablets, human blood serum, and urine samples. The detected amount in tablets were in the range 98.4–103.2 % of their labeled value. Spike recovery results in human blood serum, urine, and tablet samples were 99.35–100.28 %, 99.03–100.32 %, and 98.40–100.41 %, respectively. Interference recovery results with less than 4.60 % error, the lower limit of detection and the wider dynamic range than most of the previously reported methods validate the potential applicability of the proposed method for CQP determination in various real samples with complex matrices.