A validated stability indicating RP-HPLC method for simultaneous estimation of Clinidipine and Valsartan in bulk and combined tablet dosage forms.

Gandla. Kumara Swamy¹*, JM Rajendra Kumar², J.V.L.N. Seshagiri Rao³.

¹Research scholar, Department of Pharmaceutical Analysis, Jawaharlal Nehru Technological University Kakinada, Kakinada - 533 003-Andhra Pradesh, India.

²Mylan Laboratories Limited, Plot no 31, 32, 33and34-A, Anrich Industrial Estate, Bollaram, Medak(Dist) 502325, India.

³Srinivasa Rao College of Pharmacy, Pothinamallayyapalem, Madhurawada, Visakhapatnam-500041.A.P.India.

*Corresponding Author E-mail:

ABSTRACT:

The simple, accurate and precise, isocratic RP-HPLC method has been developed and validated for simultaneous estimation of Clinidipine and Valsartan in bulk and tablets dosage forms. The chromatographic separation was achieved on an Waters symmetry C₁₈ (150x4.6 Id, 3.5μ) with a composition of Acetonitrile : phosphate buffer pH 3.5 adjusted with orthophosphoric acid (70:30, v/v) as mobile phase; at a flow rate of 1.0 ml/min. PDA detection of separtion was performed at 254 nm. The retention times were 2.33 and 3.55 minutes. for Clinidipine and Valsartan respectively. Calibration curves were linear (r²>0.998) over the concentration range 1.2-6.0 μg/ml for Clinidipine and 10-50μg/ml Valsartan. The method was validated for accuracy, precision, specificity, linearity, and sensitivity. The proposed method was successfully used for quantitative analysis of tablets. No interference from any component of pharmaceutical dosage form was observed. Validation studies revealed that method is specific, rapid, reliable, and reproducible. The high recovery and low relative standard deviation confirm the suitability of the method for routine determination of Clinidipine and Valsartan in bulk drug and tablet dosage form.

KEY WORDS: Clinidipine and Valsartan, RP-HPLC; Tablet dosage forms. Forced degradation studies.

INTRODUCTION:

1. Valsartan:

Chemical name: Valsartan is chemically 3-methyl-2- (pentanoyl-(4-(2-(2H-tetrazol-5-yl) phenyl) phenyl) methyl)amino)- butanoic acid (Fig. 1), angiotensin II receptor antagonist, acting on the AT1 subtype and used for treatment of high blood pressure, of congestive heart failure, and post-myocardial infarction(MI). By blocking the action of angiotensin, valsartan dilates blood pressure. The Molecular Formula – C₂₄H₂₉N₅O₃ and_, Molecular Weight – 431.5188 .It is Solubile in various polar and Non Polar solvents like – Soluble in Acetonitrile , practically insoluble in water.