ECOFRIENDLY VALIDATED SPECTROPHOTOMETRIC METHODS FOR THE ESTIMATION OF AMLODIPINE BESYLATE IN PURE AND PHARMACEUTICAL FORMULATIONS USING HYDROTROPIC SOLUBILIZATION

Makka Hashim Ahmed*, Mohamed El-Mukhtar and A. E. M. Saeed

ABSTRACT

Simple sensitive and accurate spectrophotometric methods were developed for determination of poorly water
soluble Amlodipine Besylate (AML) in pure and pharmaceutical dosage form using three hydrotropic agents
ammonium acetate (method 1), potassium acetate (method 2) and nicotineamide (method 3). Hydrotropy is a good
choice for replacing organic solvents used for this kind of drugs to reduce the cost and hazards of the analytical
method. Amlodipine Besylate shows maximum absorption at 365 nm in 0.5 M of the three hydrotropic agents. All
hydrotropic agents did not show any absorbance above 250 nm so there is no interferences. Beer’s law was found
to be obeyed in the concentration range of 5 - 90 μg/mL for the three hydrotropes. Limit of detection was found to
be 1.072, 0.646 and 0.866 μg/mL and limit of quantification was 3.249, 1.956 and 2.625 μg/mL for ammonium
acetate, potassium acetate and nicotineamide, respectively. The results were in a good agreement with those
obtained with official USP method.

Keywords: Amlodipine Besylate, colorimetry, hydrotropy, method validation.