ISSN 2320-5407 International Journal of Advanced Research (2014), Volume 2, Issue 5, 1096-1109 1096 Journal homepage: http://www.journalijar.com INTERNATIONAL JOURNAL OF ADVANCED RESEARCH RESEARCH ARTICLE New potentiometric membrane sensors for determination of alverine citrate in pharmaceutical compounds and biological fluids M. M. Khalil 1, *, Y. M. Issa 2 , S. I. M. Zayed 3,4 , F. Q. Ali 1 1. Chemistry Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt 2.Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt 3. Faculty of Industrial Education, Beni-Suef University, Beni-Suef, Egypt 4.Chemistry Department, Faculty of Science, Taif University, Taif, KSA . Manuscript Info Abstract Manuscript History: Received: 22 March 2014 Final Accepted: 23 April 2014 Published Online: May 2014 Key words: Alverine citrate; Potentiometry; Sensors; Electron microscopy; Pharmaceutical formulations; Biological fluids. *Corresponding Author M. M. Khalil The construction and performance characteristics of novel alverine citrate (Alv) plastic membrane electrodes based on incorporation of alverine citrate with the ion exchangers, sodium tetraphenylborate (Alv-TPB), ammonium reineckate (Alv-Rt) and a mixture of both (Alv-TPB/Rt) into plasticized poly(vinyl chloride) membrane are described. The sensors showed a near- Nernstian slope of 57.24, 56.31 and 57.01 mV decade -1 at 25±0.1°C within the concentration range 1.00×10 -5 –1.00×10 -2 , 1.99 ×10 -5 -1.00×10 -2 and 3.98×10 -5 -1.00×10 -2 M Alv, with detection limits of 4.07×10 -6 , 3.98×10 -6 , 9.33× 10 -6 M Alv for Alv-TPB, Alv-Rt, Alv-TPB/Rt electrodes, respectively. The membrane electrodes performed satisfactorily over pH ranges of 1.48– 7.56, 1.52–7.97 and 1.56–7.82 for the three electrodes, respectively. The selectivity coefficients of the developed sensors indicated excellent selectivity for Alv. Surface analysis using scanning electron microscopy was used to determine the cause of the limited life span of plastic membrane electrode. The proposed sensors displayed useful analytical characteristics for the determination of Alv in pharmaceutical preparation and biological fluids such as plasma and urine samples. Copy Right, IJAR, 2014,. All rights reserved. 1. Introduction Alverine citrate (Figure 1), N-methyl-N-(3-phenylpropyl)benzenepropanamine citrate, is a commonly used smooth muscle relaxant agent [1]. It has been used in the treatment of irritable bowel syndrome [2]. It decreases the sensitivity of the intestinal mechanoreceptors in response to chemical stimulation in anaesthetized cats [3] and reduces 5-hydroxytryptamine 1A receptor-mediatd rectal hypersensitivity in the rat [4]. Hayase et al. investigated the mechanisms underlying the paradoxical ability of Alverine to enhance spontaneous activity in smooth muscles while suppressing evoked activity. They have, however, come to the conclusion that further research has to be carried out for assessing the therapeutic potential of ALV to treat detrusor smooth muscle dysfunction [5]. It was able to inhibit the spontaneous contractions and the nervous control of rabbit proximal colon [6]. It was also found to induce the hepatitis [7]. Recently, this drug has been determined by liquid chromatography tandem mass spectrometry [8,9]. This method requires prior derivatization or extraction step, and involves the use of expensive equipment. On the other hand, potentiometric sensors offer simple, selective and sensitive technique for drug analysis, therefore, has had wide applications in this field. However, no potentiometric membrane sensors have been developed and used for alverine determination yet. In connection with our continuing research oriented towards construction and analytical applications of ISEs [10-15], the present work describes preparation and investigation of performance characteristics of new ISEs based on PVC for the determination of alveine citrate in pure solutions, pharmaceutical preparations and biological fluids (spiked urine and plasma).