Formulation and In-Vitro Evaluation of Alfuzosin-Loaded Sodium Alginate Microspheres for Controlled Release in Benign Prostatic Hyperplasia

Abstract

This study sought to develop and assess sodium alginate-based microspheres of alfuzosin for the controlled release of medication in the treatment of benign prostatic hyperplasia (BPH). Alfuzosin, noted for its brief biological half-life and frequent dosing necessities, is an ideal candidate for sustained-release delivery methods. Microspheres were synthesised via the ionotropic gelation method, utilising sodium alginate as the principal polymer and calcium chloride as the cross-linking agent. Five formulations (F1–F5) were created by altering alginate concentration while keeping the medication load constant. Preformulation experiments demonstrated exceptional linearity of alfuzosin within the range of 5–25 µg/mL (R² = 0.999), hence verifying UV spectrophotometric analysis. The synthesised microspheres displayed a smooth, spherical morphology, with particle size escalating from 142.6 ± 4.8 µm to 238.9 ± 8.1 µm as polymer concentration augmented. Entrapment efficiency markedly increased from 61.4 ± 2.3% to 87.4 ± 3.6%, although drug content remained consistent (94.8–99.3%). In vitro dissolution tests revealed polymer-dependent drug release, with the optimised formulation F5 attaining sustained release for up to 12 hours. Release kinetics demonstrated a transition from Higuchi diffusion to near zero-order release at elevated polymer concentrations, with the Korsmeyer–Peppas model indicating anomalous transport behaviour. The stability investigations validated the resilience of the optimised formulation. Sodium alginate microspheres constitute a promising controlled-release mechanism for once-daily alfuzosin treatment in benign prostatic hyperplasia (BPH).