Simultaneous determination of amlodipine and losartan using an iron metal–organic framework/mesoporous carbon nanocomposite-modified glassy carbon electrode by differential pulse voltammetry

Abstract

The present work proposed a simple and convenient electroanalytical method for the selective and simultaneous determination of anti-hypertensive drugs viz. amlodipine (AML) and losartan (LOS). The electrochemical response of AML and LOS was investigated at a glassy carbon electrode (GCE) modified with an iron metal–organic framework/mesoporous carbon (FeMOF/MC) nanocomposite by employing differential pulse voltammetry (DPV). Under the optimized experimental conditions, electrochemical sensing of both the molecules was performed at the FeMOF/MC/GCE in 0.1 M phosphate buffer (PBS) of pH 6.0. The DPV experiments revealed that the voltammetric signals of AML and LOS were very well resolved and separated with a potential difference of 50 mV. Also, the FeMOF/MC composite exhibited unique properties in terms of porosity, surface area and high electrical conductivity. As compared to the plain GCE, the modified electrode showed a thirteen- and nineteen-fold enhancement in the oxidation peak current of AML and LOS which indicates that the synergy of electrode materials provides excellent electrocatalytic activity towards the simultaneous determination of AML and LOS. The analytical curve of AML and LOS showed a linear response in the concentration range of 0.009 μM to 500 μM with a detection limit of 1.27 nM and 2.03 nM, respectively. The practical analytical utility of the proposed sensor was evaluated by employing the present method for simultaneous determination of AML and LOS in pharmaceutical formulations, and human blood serum, saliva and urine samples.