Fabrication of MoS2 QD-AuNP Modified Screen Printed Electrode for the Improved Electrochemical Detection of Cefixime
Herein we report a voltammetric method for the nanomolar detection of Cefixime, a third generation antibiotic. Determination of Cefixime is validated on glassy carbon electrode (GCE) as well as Screen printed carbon electrode (SPCE). In the present work a simple one hand synthesis of MoS2 quantum dots (QDs) by hydrothermal method and further MoS2 QDs-gold nanoparticle(MoS2 QD-AuNP) composite by the addition of aurochloric acid has been reported. The as synthesized nano composite is characterized by UV-Vis, FTIR, XRD, TEM and EDX and further applied in modification of working electrodes, showing excellent electroactivity. Sensing of Cefixime is done by cyclic and differential pulse voltammetry techniques. Presence of only anodic peak in the voltammogram reveals the irreversible oxidation of Cefixime in the potential range about 1.3+0.1V vs Ag/AgCl. Study is also performed at different scan rate, which indicate diffusion controlled mechanism. Proposed Cefixime sensor showed linear response in the concentration range of 0.33-90.82 μM (at S/N = 3) with limit of detection (LOD) 3.9-4.5 nM. The electrochemical sensitivity is calculated as 8.63μA/μM/cm2and 7.07 μA/μM/cm2 in buffer and pharmaceutical formulation (commercially available Cefixime tablet) respectively. The effect of several interferents is also investigated. Proposed sensor probe is effectively used for estimating Cefixime in phosphate buffer and commercially available Cefixime tablet viewing no cross reactivity or matrix effects and shows gigantic prospective for real application.