Research J. Pharm. and Tech. 14(4): April 2021 1 ISSN 0974-3618 (Print) www.rjptonline.org 0974-360X (Online) RESEARCH ARTICLE A Bioanalytical Method for Quantification of Telmisartan in rat Plasma; Development, Validation and Application to Pharmacokinetic Study Khater Ahmed Saeed AL-Japairai 1,3 , Bappaditya Chatterjee 2,3 *, Syed Mahmood 1,4 , Samah Hamed Almurisi 3 1 Department of Pharmaceutical Engineering, Faculty of Chemical and Process Engineering Technology, University Malaysia Pahang, Gambang 26300, Malaysia. 2 SPP School of Pharmacy and Technology Management, SVKM’s NMIMS, Mumbai, India. 3 Department of Pharmaceutical Technology, Kulliyyah of Pharmacy, International Islamic University Malaysia (IIUM), Kuantan 25200, Malaysia. 4 Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Malaya, 50603, KL, Malaysia. *Corresponding Author E-mail: bdpharmaju@gmail.com ABSTRACT: The telmisartan was determined in a rat plasma using developed and validated a reversed-phase high performance liquid chromatographic (HPLC). The pre-treatment of the plasma sample involving liquid-liquid extraction using ethanol as the extracting solvent. The HPLC method validation has been shown a linear calibration curve over a plasma concentrations range of 0.7 to 10μg/mL with a correlation coefficient of 0.9979, the limit of detection and the limit of quantification were determined to be 0.025μg/ml and 0.07μg/ml, respectively. The precision and accuracy were in an acceptable limit. The pharmacokinetic parameters of telmisartan were adequately evaluated following a single oral dose (4mg/kg) in Sprague-Dawley rats. The results observed conclude that the developed bioanalytical HPLC method is appropriate and applicable as an analytical tool in the pharmacokinetic study of telmisartan. KEYWORDS: Telmisartan, HPLC, Validation, Bioanalytical method, Rat plasma. INTRODUCTION: The bioanalytical method is employed for the quantitative estimation of drugs and their metabolites in biological media. It plays an important role in the estimation and interpretation of bioequivalence, pharmacokinetic and toxic kinetic studies 1-3 . The sensitivity and selectivity of bioanalytical methods are necessary in order to conduct preclinical and clinical studies successfully during the drug development process from the initial preclinical phase to the final clinical steps 4,5 . The chromatographic method is the most commonly used technology for the bioanalysis of small molecules 6 . Received on 17.04.2020 Modified on 31.05.2020 Accepted on 02.07.2020 © RJPT All right reserved Research J. Pharm. and Tech. 2021; 14(4):. DOI: Telmisartan (TEL) is chemically described as [1,1- biphenyl]-2-carboxylic acid, 4-[(1,4-dimethyl-2- propyl[2,6-bi-1H-benzimidazol]-1-yl)methyl] 7 , the chemical structure of TEL is shown in Fig.1 8 . It is an angiotensin II receptor antagonist (ARB) used in the treatment of hypertension. The high affinity of angiotensin II receptor blockers (ARBs) such as telmisartan to the angiotensin II type 1 (AT1) receptors leading to inhibition of the action of angiotensin II on vascular smooth muscle, which in turn result in a reduction in arterial blood pressure 9,10 . The present study describes a simple and reproducible HPLC method using liquid-liquid extraction to detect the plasma concentrations in male Sprague-Dawley rats. The applicability of pharmacokinetic is also demonstrated. Figure 1: Chemical structure of TEL.