Application of Montmorillonite Clay and Mesoporous Carbon as Modifiers to Carbon Paste Electrode for Determination of Amoxicillin Drug

Two types of mesoporous carbon (MC and MC−) were prepared. MC was synthesized using the prepared SBA-15 as a hard template and sucrose as the carbon source. While, MC− has been fabricated using polyethylene-polypropylene glycol (F127) as a soft template and resorcinol as a carbon source. The prepared mesoporous carbon and commercial sodium montmorillonite clay (Na-MMT) were characterized using X-ray diffraction (XRD), N2 adsorption isotherm (BET), scanning electron microscope (SEM) and transmission electron microscope (TEM). Carbon paste electrode modified with MC, MC− as well as Na-MMT were used as sensors for determination of amoxicillin drug using linear sweep and square wave adsorptive anodic stripping voltammetry (LS- and SW-AdASV) methods. The most developed peak current was observed at MC modified carbon paste electrode (MC/CPE) indicating its strongest adsorptive property which can be attributed to its highest surface area and lowest charge transfer resistance. MC/CPE was successfully applied for the determination of amoxicillin drug in its pharmaceutical formulation and in biological fluids. LOD values of 6.0 × 10−9 and 1.5 × 10−9 M bulk amoxicillin were obtained using LS- and SW-AdASV, respectively.