Research Article UTILITY OF COMPLEXATION REACTION FOR THE DETERMINATION OF SOME CARDIOVASCULAR DRYGS MAGDA AYAD, HISHAM ABDELLATEF,MERVAT HOSNY * and YASSMIN SHARAF Analytical Chemistry Department, Faculty of Pharmacy, Zagazig University,Zagazig, (EGYPT),44519,Email: mermaka89@yahoo.com Received:16 November 2012, Revised and Accepted:28 December 2012 ABSTRACT Two simple, sensitive and accurate extraction spectrophotometric methods were developed for the determination of propafenone HCl,naftidrofuryl oxalate and bisoprolol hemifumarate both in pure form and in pharmaceutical preparations. The first method based on the formation of ion -pair complexes between the cited drugs and two dyes namely tropeolin OOO or chromazurol S using extractive procedure . The calibration plots were rectilinear over concentration range of 6-28 ,6-32 and 6-28 μg/mL with limits of detection of 1.45,1.38 and 0.99 μgmL -1 for propafenone HCl, naftidrofuryl oxalate and bisoprolol hemifumarate respectively in case of tropeolin OOO; 28-100, 28-68 and 10-46 μg mL -1 with limits of detection of 5.1,5.4,2.7 μg mL -1 in case of chromazurol S. The second method based on the formation of ternary complex between the cited drugs and the binary inorganic complex Mo(V)-thiocyanate followed by extraction with methylene chloride . Beer's law was obeyed in the concentration range of 4-32, 6-32 and 4-32 μg ml -1 with limits of detection of 1,1.11,1.13 μgmL -1 for propafenone HCl, naftidrofuryl oxalate and bisoprolol hemifumarate respectively. The different experimental parameters affecting the development of the complex were studied and optimized. Statistical comparison of the results was performed using Student's t-test and variance ratio F-test at 95% confidence level and there was no significant difference between the proposed methods and the official or reference methods. Rapid and short analysis time, simplicity, sensitivity, low cost compared with other techniques, make the method attractive for analysis of the cited drugs in pure forms and in pharmaceutical preparations. Keywords: Cardiovascular, Extractive, Spectrophotometric, Tropeolin OOO, Chronazurol S, Mo(V)- thiocyanate INTRODUCTION Propafenone hydrochloride [2-(2-hydroxy-3-propylaminopropoxy)- 3-phenylpropiophenone hydrochloride] 1. It is used in the treatment of cardiac arrhythmias 2. Several methods including Spectrophotometric 3,spectrofluorimetric 4, capillary electrophoresis 5-7, Conductometric8, HPLC methods 9-10 , LC-MS 11-12, adsorptive stripping voltammetry13, gas chromatography using chemical ionization mass spectrometry (CIMS)14 and TLC- densitometric determination15 were reported for propafenone determination . Naftidrofuryl oxalate is also known as nafronyl oxalate,(2- (diethylaminoethyl)-2-[(naphthalene-1-yl)methyl]-3- (tetrahydrofuran-2-yl)propanoate hydrogen oxalate) 16. It is used as a vasodilator in the treatment of peripheral and cerebral vascular disorders. It is claimed to enhance cellular oxidative capacity thereby protecting cells against results of ischaemia 2. Various analytical methods were reported for the determination of naftidrofuryl in biological fluids and/or pharmaceutical preparations. Most of these studies foccused on kinetic spectrophotometry 17, derivative spectrophotometry, spectrofluorimetry, differential-pulse voltammetry 18, HPLC19-21 . Others include phosphorimetric analysis 22-23, potentiometric method with nafronyl ion-selective electrodes24 and flow injection analysis with fluorescence optosensor 25. Bisoprolol Hemifumarate , 1-[4-[[2-(1- methylethoxy)ethoxy]methyl]phenoxy]-3-[(1-methylethyl) amino2- Propanol fumarate (2:1), is a highly selective_1-receptor blocking agent used for the treatment of hypertension and angina pectoris 2. Several methods were used including Spectrophotometric26-27 , volttametric 28, capillary electrophoresis29 , GC-MS 30, LC- chemilumesence nitrogen detection31 , Densitometric32, potentiometric33, flourometric34 and HPLC methods 35,36. Bisoprolol were determined with Hydrochlorothiazide or Amlodipine besylate in combined pharmaceutical dosage forms using RP-HPLC37 , HPLC-MS38, HPLC39 and Spectrophotometric methods 40-43. The present study deals with development and validation of visible extractive spectrophotometric methods for the determination of the cited drugs in bulk form and pharmaceutical preparations. The methods in addition to being selective, is sensitive, simple, cost effectiveness, there is no need of heating or expensive device. An inspection of the performance characteristics of the reported visible spectrophotometric methods for the studied drugs ,some of them suffer from some drawbacks as law sensitivity , too many steps and heating at higher temperatures hence the present work aims to demonstrate ,simple and sensitive spectrophotometric method using simple steps and ecofriendly chemicals for estimation of the mentioned drugs in pure and pharmaceutical dosage forms. EXPERIMENTAL Instrumentation A Shimadzu UV and visible recording spectrophotometer (UV 260) with two 10-20 mm matched quartz cells were employed for all absorbance measurements. Materials and reagents All solutions were prepared with analytical-reagent grade chemicals and water was always doubly distilled. The studied drugs were of pharmaceutical grade. In the first method 0.1% aqueous solution of Tropeolin OOO (Prolabo) was prepared, while Chromazurol S was prepared as 0.1% and 0.3% aqueous solutions. In the second method, 8% and 12% aqueous solutions of ammonium thiocyanate,2% and 2.5% aqueous solutions of sodium molybdate (Fluka AG,Buchs SG) were used . Acetate buffers pH 2.7 and 3.7 16, buffer solution of pH 1.1 44, ,10%aqueous solution of ascorbic acid , 5M HCl were used. Standard solutions Solutions of 0.4 mg mL -1 of Naftidrofuryl oxalate( drug ( Mina Pharm, under licence of Merck Santé France), Propafenone HCl( Kahira pharm, and chem. Ind. Co., under the licence from Abott Laboratories) and Bisoprolol hemifumarate( Amoun Pharm, under licence of Merk Santé France) were prepared by dissolving 10 mg of drug in 25 mL distilled water. Pharmaceutical preparations Rytmonorm® tablets containing 150mg Propafenone HCl per tablet (Kahira pharm, and chem. Ind. Co., under the licence from Abott Laboratories). Praxilene® tablets containing 200 mg Naftidrofuryl oxalate per tablet (Mina Pharm, under licence of Merck Santé France) Asian Journal of Pharmaceutical and Clinical Research Vol 6, Suppl 1, 2013 ISSN - 0974-2441 Academic Sciences