Selective electrochemical sensing of cefixime by silver nanoparticle amalgam paste microelectrode

A new electrochemical method for the detection of cefixime (CFX) was developed by fabricating a silver nanoparticle amalgam paste microelectrode (AgNP-APME) equipped with square wave cathodic stripping voltammetric (SW-CSV). The proposed sensor was fabricated using the micro pipette tip and tied with the AgNP amalgam paste and pure copper wire used as a connector. Electrochemical detection of CFX achieved at the optimized conditions in a phosphate buffer of pH 3 with deposition time and potential of 15 s and 0.3 V, respectively. A well-defined two reduction peaks were observed in the electrochemical studies of CFX on the AgNP-APME. The linear voltammetric response related to the CFX concentration was observed in the range of 0.1-1.60 mu M and has a co-efficient of determination (R-2) 0.991. The proposed method has sensed CFX in the limit of detection and quantification (LOD/LOQ) as 2.6 x 10(-8) and 8.67 x 10(-8) M, respectively. The interference study of CFX using AgNP-APME by SW-CSV showed significantly good selectivity for the detection of CFX with RSD < 2.0%. Moreover, the proposed electrochemical method based on the accuracy, precession, sensitivity, and selectivity for CFX was significantly higher in comparison to the reported electrochemical and spectroscopic methodologies (p > 0.05). Moreover, the developed method was successfully utilized for CFX in pharmaceutical preparations and biological liquids and showed excellent recoveries.