Objective: In response to the low bioavailability of Naftopidil (NAF) attributed to its poor solubility, permeability, and extensive first-pass metabolism, this study aimed to enhance its oral bioavailability by formulating solid lipid nanoparticles (SLNs) of NAF.
Methods: SLNs loaded with NAF were prepared using the solvent emulsification/evaporation method, employing Compritol 888 ATO and Poloxamer 188 as excipients. Among the formulations, F10 exhibited superior entrapment efficiency (EE), prompting its selection for further optimization of particle size, zeta potential, surface morphology, Fourier transform infrared spectroscopy (FTIR), in vitro drug release, and stability assessments.
Results: Successful incorporation of NAF into SLNs was confirmed, with EE ranging from 56% to 88%, drug loading between 17% and 20%, and drug content from 77% to 98%. Formulation F10 demonstrated a particle size of 270.2 nm, zeta potential of 21.7 mV, and FTIR analysis indicated no interactions between the drug and lipid components. In vitro release studies revealed a significant increase in NAF release from SLNs, reaching up to 82.418% in pH 6.8 buffer. The release data were best fit to the Korsmeyer-Peppas model, with a high correlation coefficient (R² = 0.916). Stability studies suggested improved formulation stability and potential enhancement of bioavailability.
Conclusion: This study underscores the potential of SLNs as an effective nano platform for enhancing the oral bioavailability of NAF. The successful formulation, characterization, and stability evaluation of NAF-loaded SLNs provide valuable insights for future pharmaceutical development aimed at improving the therapeutic efficacy of NAF formulations.