Determination of Losartan in Real Samples Using Liquid Membrance Graphite Electrode Based on Molecularly Imprinted Polymer

A Molecularly Imprinted Polymer (MIP) is a polymer that has been processed using the molecular imprinting technique which leaves cavities in polymer matrix with affinity to a chosen template molecule. Fast and cost-effective molecularly imprinted polymer technique has applications in many fields of chemistry, biology and engineering, particularly as an affinity material for sensors, detection of chemical and byproduct removal in chemical reaction [1].Losartan is a powerful and selective antihypertensive administered orally, blocking the interaction between angiotensin and the receptors with the advantage of not affecting bradicinina [2]. Several analytical methods have been applied to the analysis of losartan potassium inbiological fluids, such as using high performance liquid chromatography technique (HPLC), thin layer chromatography (HPTLC), capillary electrochromatography (CEC), capillaryelectrophoresis (CE) and spectrophotometry [3]. Some of these methods are not simple; others are time consuming or involve procedures with rigorous control of the experimental conditions or suffer interference from the tablet matrix and consequently are not suitable for routineanalysis. In this work, a potentiometric sensor was fabricated based on molecularly imprinted polymer for the recognition and determination of losartan. The best response was obtained with the membrance having 30 mg PVC, 20 mg MIP and 50 mg dibutyl phethalate. In optimalcondition electrode has good behavior Nernst slope in a wide concentration rang 1.0 × 10 -8 to 1.0 × 10 -2 mol L-1 with a lower detection limit. The electrode was successful for measuring losartan potassium in biological samples such as urine and plasma. The sensor show highselectivity and a sensitive response to the template in aqueous system. The electrode has high performance, high sensitivity and good long term stability (more than 5 months). The method was satisfactory and used to the cetirizine assay in tablets and biological fluids.

Keywords:

Molecularly Polymer , Potentiometric sensor , Losartan potassium , Biological samples