Determination of Specific Absorbance (A¦) of Five Calcium Channel Blocker Anti-Hypertensive Drugs Using UV-Visible Spectroscopy

This study focuses on determining the Specific absorbance A¦, and Molar absorptivity (ε) of five standard Anti-Hypertensive drugs sourced from the Indian Pharmacopoeia Reference Standard (IPRS) using a simple and accessible analytical technique, UV-Visible Spectroscopy. The drugs analysed were Nifedipine (ND), Felodipine (FD), Amlodipine Besylate (AB), Verapamil HCl (VP), and Diltiazem HCl (DT). Absorbance measurements were conducted at concentrations of 0.01 mg/mL, 0.02 mg/mL, and 0.04 mg/mL over three consecutive days. ND and FD were dissolved in methanol, while AB, VP, and DT were
dissolved in 0.1N HCl aqueous solution.
The parameters examined in this study hold significant importance in pharmaceutical quality control. A¦ is a key indicator of a drug’s identity and helps in quantitative analysis by providing reproducible reference values. Molar absorptivity (ε) indicates how much a substance absorbs light at a specific wavelength, reflecting the drug’s purity and concentration, ensuring whether the drug meets pharmacopeia standards and contains minimal impurities. Together, these parameters play a crucial role in monitoring the quality and efficacy of medications, ensuring that medicines consumed daily by patients maintain safety, reliability, and therapeutic effectiveness.
By employing a straightforward yet effective method like UV-visible spectrophotometry, this research provides an accessible approach to routine pharmaceutical analysis, promoting better drug validation practices in laboratories.