Analytical Comparison of Cefadroxil Determination by Square Wave Adsorptive Stripping Voltammetric and Spectrophotometric Methods

The goal of this research is to verify the proposed nano-silver amalgam paste electrode (Ag-nano-SPE) method to compare with a spectrophotometric technique based on derivatization with potassium periodate (KIO4 ), 2,4-dinitrophenyl hydrazine (DNP) and sodium hydroxide (NaOH) for the estimation of cefadroxil (CFDL) by square wave adsorptive stripping voltammetry (SWAV). The different parameters of both methods were optimized in detail separately and then compared their efficiency, selectivity, sensitivity and applications. The SWAV produced a reduction peak with a precise definition at -0.160 V while measuring CFDL in 0.04 molL-1 Britton–Robinson buffer at pH 4, accumulation potential (0.5 V), accumulation time (10 sec), and with stirring rate of 200 rpm. Whereas, the CFDL was measured at 515 nm (λmax) by UVVisible spectrophotometer after the derivatization by using 1.5 mL of 0.5 mM DNP, 1.5 mL of 6.52 mM KIO4 and 0.5 mL of 10 M NaOH solution at room temperature. The linear response for CFDL was found using the SWAV and spectrophotometric techniques along a linear dynamic range from 0.033 - 0.304 and 0.051 - 1.376 µM, respectively. However, the precision, detection limit and quantification limit of SWAV for CFDL in the samples and standards significantly lower (p <0.01) as compared to spectrophotometric method. This indicates that the SWAV is more sensitive and selective than the spectrophotometric technique for regular CFDL analysis.