Abstract
A cobalt oxide nanoparticles (Co(3)O(4)NPs) and multi walled carbon nanotubes (MWCNTs) modified carbon paste electrodes were used to study the electrochemical behavior of linagliptin and empagliflozin in Britton Robinson buffer solution of pH 8.0 using cyclic and square wave voltammetry. The above mentioned modified electrodes showed highly sensitive sensing and gave an excellent anodic response for both drugs. The peak current varied linearly over the concentration ranges: 3.98x10(-5)-1.53x10(-3) mol L-1 (18.82-723.00 mu g/mL) and 7.94x10(-6)-1.07x10(-4) mol L-1 (3.65-48.25 mu g/mL) with determination coefficients of 0.9999 and 0.9998 for linagliptin and empagliflozin, respectively. The recoveries and relative standard deviations were found in the following ranges: 98.80 %-102.00 % and 0.23 %-1.90 % for linagliptin and 98.30 %-101.80 % and 0.11 %-1.86 % for empagliflozin. The detection and quantification limits were 1.13x10(-5) and 3.76x10(-5) mol L-1 (5.34and17.77 mu g/mL) for linagliptin, 1.71x10(-6)and 5.68x10(-6) mol L-1 (0.77 and 2.56 mu g/mL) for empagliflozin. The proposed sensors have been successfully applied for the determination of the drugs in bulk, pharmaceutical formulations and biological fluids.