Ionic liquid wrapped Co3O4 embedded N doped porous carbon for the precise monitoring of salbutamol in urine samples for dope tests

Abstract

Salbutamol (SAL) is a β2-agonist and belongs to a category of drugs used to maintain bronchodilation. Unfortunately, some athletes have misused these medications as performance-enhancing drugs to improve their performance. Thus, to ensure fair competition, the World Anti-Doping Agency (WADA) prohibits its usage among athletes. Herein, we have designed, a novel, non-enzymatic electrochemical sensor by wrapping benzimidazolium-1-acetate liquid (IL) around Co₃O₄ (derived from the pyrolysis of ZIF-67) embedded in N-doped porous C (IL@NC–Co), for the detection of SAL in urine for dope tests. The fabricated material was characterized through SEM, XRD, and FTIR techniques, which confirmed the successful synthesis of the material. The designed novel IL@NC–Co electrochemical sensor showed excellent electrocatalytic activity because of its highly porous structure and fast electron transfer due to the presence of carboxyl functional groups and aromatic rings in IL, thus resulting in an enhanced current response. The developed sensor exhibited excellent selectivity even in the presence of co-existing interferences and good sensitivity (0.0039 μA nM⁻¹ cm⁻²) with a linear response to SAL concentrations ranging from 2 to 2500 μM with a low detection limit of 0.0014 nM. The designed electrode showed an excellent stability of 96.58% with RSD 2.45% even after 24 h. The fabricated electrode was successfully utilized for selective monitoring of SAL in urine samples, thus suggesting the reliability of the designed system to be applicable for dope tests.