Electrochemical determination of Saxagliptin hydrochloride with MWCNTs/ CuO/4 ' aminobenzo-18-crown-6-ether composite modified carbon paste electrode

摘要

A new carbon paste electrode was developed using the carboxyl-functionalized MWCNTs-CuO nanocomposites that were covalently attached to 4'-aminobenzo-18-crown-6-ether for the potentiometric determination of saxagliptin hydrochloride. As far as we are concerned, this is the first time that this kind of nanocomposite material is reported. The prepared nanocomposite was characterized by FTIR, XRD, and TEM. In comparison to their non-covalent attachment, the covalent-linked nanocomposite based sensor showed better response characteristics. The sensor showed a Nernstian slope of 58.79 mV/concentration decade and a linearity range of 1 x 10(-3) to 1 x 10(-10) mol L-1 with a correlation coefficient of 0.996. It showed high sensitivity with LOD of 8.5 x 10(-11) mol L-1. The sensor was efficiently applied for the estimation of saxagliptin in bulk, pharmaceutical tablets and spiked biological fluids. The average recoveries from the tablets were from 96.89% to 99.05% with a standard deviation of 0.83% and recoveries from plasma samples were from 95.56% to 99.74% with a standard deviation of 1.02%. The recoveries from urine samples were ranged from 100.94% to 96.68% with a standard deviation of 1.74%. The studied sensor revealed higher selectivity towards saxagliptin, long lifetime and fast response time.