An innovative electrochemical platform for the sensitive determination of the hepatitis B inhibitor Entecavir with ionic liquid as a mediator

We report on a facile method to fabricate nanoparticles-modified carbon paste electrodes with high sensitivity and reactivity towards the electrochemical determination of Entecavir (ENT), allowing for optimal charge transfer/electrode kinetics. The use of ionic liquid provides wider electrochemical window that facilitates the effective determination of ENT. The electrochemical platform is based on mixing NiFe2O4 nanoparticles with room temperature ionic liquids into carbon paste electrode (NiFe2O4-IL/CPE). The synthesized composite is characterized using different techniques. Outstandingly, the physical properties of the NiFe2O4 nanoparticles, regarding the shape, size, structure, area, and porosity control the electrochemical processes at the surface of the sensor. The sensing of ENT via square wave voltammetry (SWV) is found to exhibit two wide linear dynamic ranges of 0.80 x 10(-8)-2.20 x 10(-6) mol L-1 and 2.20 x 10(-6)-1.55 x 10(-4) mol L-1 at pH 2.0. The NiFe2O4-IL/CPE sensor is explored towards the analysis of ENT in urine, plasma and pharmaceutical products. The fabricated NiFe2O4-IL/CPE has the potential to be used as a clinical assay and QA in pharmaceutical products. (C) 2020 Elsevier B.V. All rights reserved.