Development and Validation of an RP-HPLC Method for Quantification of Felodipine in Drug-Loaded Liposomes

The current study was aimed at developing a simple, sensitive, and rapid reverse-phase high-performance liquid chromatographic (HPLC) method for the quantification of felodipine and its lipid-based pharmaceutical formulations, e.g., liposomes. The drug sample (felodipine) was eluted isocratically using a mobile phase of 0.01 N phosphate buffer solution and acetonitrile at a ratio of 20:80 (v/v) on a Phenomenex C-18 (150 mm × 4.68 mm) analytical column. At a UV wavelength of 234 nm, the drug was quantitatively determined using a standard calibration curve spanning the range of 2–50 μg/mL. The results showed that the limits of quantitation and detection were 0.09 and 0.03 μg/mL respectively. For both the intra-day and inter-day analysis, relative standard deviation was found to be less than 2%, and the drug’s percentage accuracy was found to be within an acceptable range. As per the established protocols, the developed method was quantitatively assessed for its intended use in terms of specificity, linearity, accuracy, precision, robustness, and sensitivity analysis. Felodipine-loaded liposomes, which are lipid-based membrane-like cell structures, were effectively used to determine the drug entrapment efficiency using the currently validated RP-HPLC method.