Voltammetric Determination of Trimethoprim Using a Glassy Carbon Electrode Modified with Printex(6L) Carbon and Gold Nanoparticles

Abstract

This work proposes a simple, fast and low-cost voltammetric method for the determination of trimethoprim at low concentrations in an analytical and real matrix (river water sample, bovine serum and synthetic urine). For this, a glassy carbon electrode was modified with Printex(6L) carbon and gold nanoparticles in a chitosan film crosslinked with epichlorohydrin. After that, the electrochemical measurement system contained a solution of phosphate buffer at pH 4.0 with commands for the square wave voltammetry technique. The results achieved showed a limit of detection equal to 12.4 nmol L−1 and a linear concentration range from 0.20 to 6.0 μmol L−1. The sensor selectivity was tested in the presence of various electroactive molecules, and the results showed that the detection of TMP in the presence of possible interferents was not masked. In addition, the applicability of the AuNPs–Printex(6L)–CTS:EPH/GCE sensor was also verified in synthetic samples of urine, bovine serum and river water through standard addition and recovery tests. Finally, the results of this analytical proposal portray a simple, fast and efficient method for the detection of TMP in different matrices.

Voltammetric Sensing of Nifedipine Using a Glassy Carbon Electrode Modified with Carbon Nanofibers and Gold Nanoparticles

“…In recent decades, carbon-based materials have garnered significant attention due to their structural and morphological properties [ 13 , 14 , 15 ]. Those materials have active centers that generate faradaic and reversible oxidation and reduction reactions originating from interactions between an ionic solution and carbon [ 16 ].…”