Dispersive Solid Phase Extraction Using Folic Acid Coupled with a Modified Glassy Carbon Electrode for Electrochemical Sensing of Favipiravir in Urine and Water Samples

An acid-base reaction-based dispersive solid-phase extraction approach was developed for extracting favipiravir before its determination using an electrochemical sensor. The analyte was extracted from the samples using folic acid as an adsorbent. Cu@MoO2 nanoparticles were synthesized by chemically reducing CuMoO4 with NaBH4 and nitrogen-rich carbon (N-C) was prepared from safranine-O dyes. The characterized Cu@MoO2/N-C composites were used as an electrode modifier. The linear range and detection limit of the favipiravir were found to be 0.01-10 mu M and 0.7 nM, respectively. The developed system was applied to determine favipiravir in urine and water samples, with recoveries of 101-102% and 97-99%, respectively.