Determination of Hydroxychloroquine by Cathodic Electrochemiluminescence.

Cathodic electrochemiluminescence (CECL) of hydroxychloroquine (HCQ) in aqueous solutions on an aluminum electrode is described. The analytical possibilities of the phenomenon are evaluated. The conditions for HCQ determination in slightly alkaline and acidic solutions are optimized.

Current-induced thermal-lens spectrometry.

A new spectroelectrochemical method using the thermal-lens effect from electrolytes using regular joule heat generation by current focusing in a small-sized channel is proposed. The experimental dependences of the signal on the analyte concentration and applied voltage are in good concordance with the theoretical estimations. A cell design providing good reproducibility and sensitivity of measurements is proposed.