Electrochemical sensor based on electropolymerized phenazine and phenothiazine dyes for neuroleptic chlorpromazine determination

Neuroleptic chlorpromazine is in the list of vital and essential drugs in Russia. Quality and dosage control is important due to the problems of falsification and the presence of serious side effects. Electrochemical chlorpromazine sensors suffer from multi-stage design and the need for use of intrinsic signals of the drug. The evaluation of the drug determination possibility using structurally similar redox-active electrode modifiers is the purpose of the research. The data obtained with cyclic voltammetry, quartz crystal microbalance and scanning probe microscopy indicate the accumulation of electrode modifiers. Electropolymerized dyes (Neutral red, thionine, Methylene blue and Methylene green) demonstrate the peak current dependence on the chlorpromazine concentration. The usage of GCE covered with polythionine allows the analyte determination in concentrations satisfied the therapeutic range. The construction protocol is simple and does not require the use of relatively expensive materials. Linear range is from 0.05 to 5 µM and LOD is 0.04 µM. The results of model samples analysis confirm the analytical capabilities of developed sensor. Promising avenues of future research in this area include the use of other aromatic azine derivatives, which could reduce detection limits while maintaining sensitivity.