Electrochemical Characterisation and Confirmation of Antioxidative Properties of Ivermectin in Biological Medium

Abstract

Ivermectin (IVM) is a drug from the group of anthelmintics used in veterinary and human medicine. Recently, interest in IVM has increased as it has been used for the treatment of some malignant diseases, as well as viral infections caused by the Zika virus, HIV-1 and SARS-CoV-2. The electrochemical behaviour of IVM was investigated using cyclic (CV), differential pulse (DPV) and square wave voltammetry (SWV) at glassy carbon electrode (GCE). IVM showed independent oxidation and reduction processes. The effect of pH and scan rate indicated the irreversibility of all processes and confirmed the diffusion character of oxidation and reduction as an adsorption-controlled process. Mechanisms for IVM oxidation at the tetrahydrofuran ring and reduction of the 1,4-diene structure in the IVM molecule are proposed. The redox behaviour of IVM in a biological matrix (human serum pool) showed a pronounced antioxidant potential similar to that of Trolox during short incubation, whereas a prolonged stay among biomolecules and in the presence of an exogenous pro-oxidant (tert-butyl hydroperoxide, TBH) resulted in a loss of its antioxidant effect. The antioxidant potential of IVM was confirmed by voltametric methodology which is proposed for the first time.

A Kinetic Approach to Oxygen Radical Absorbance Capacity (ORAC): Restoring Order to the Antioxidant Activity of Hydroxycinnamic Acids and Fruit Juices

“…Among the tested antioxidants, Trolox showed the highest repair capability for fluorescein. This ability is linked to its low redox potential (E p,a = +80 mV) [26], which is significantly lower (more reducing) than that of fluorescein (E p,a = +750 mV) [44]. The equilibrium constant K 6 ranks the monophenolic cinnamic acids as sinapic acid > ferulic acid > p-coumaric acid.…”

“…Our model integrates factors identified in previous studies, such as the formation of peroxyl and alkoxyl radicals during fluorescein bleaching [24], their differential reactivity [25], and the multifaceted reactivity of antioxidants. This includes their scavenging activity toward peroxyl radicals and their capacity to repair fluoresceinyl radicals [26,27]. Despite the inherent complexity of this model, software such as COPASI simplifies the simulation and data fitting processes, making it more manageable.…”