Development and Characterization of Nimodipine Loaded Solid Lipid Nanoparticles Using Central Composite Design: A Approach to Manage Cerebrovascular Disorders

Introduction: Nimodipine, is a dihydropyridine calcium channel blocker widely used in the treatment of cerebrovascular disorders; however, its clinical efficacy is limited by poor aqueous solubility and low oral bioavailability. Objectives: The present study was undertaken to develop and optimize Nimodipine-loaded Solid Lipid Nanoparticles (ND-SLN) to enhance its solubility, dissolution rate, and overall pharmaceutical performance. Preformulation studies, including organoleptic evaluation, melting point determination, UV spectrophotometric analysis, and solubility studies, were performed to characterize the drug. Methods: The drug exhibited a melting point of 125± 0.21°C and a maximum absorption wavelength at 240 nm. Solubility studies identified Stearic acid as the most suitable lipid, while Tween 80 and Poloxamer 188 were selected as the surfactant and co-surfactant, respectively. Drug–excipient compatibility was confirmed by FTIR spectroscopy, which showed the retention of characteristic functional group peaks without significant shifts, indicating the absence of chemical interactions between drug and the selected excipients. Nine formulations (F1–F9) were prepared using Central composite Design and evaluated for drug content, % Entrapment Efficiency (EE), Particle size, Polydispersity Index (PDI), zeta potential, and Cumulative % in-vitro drug release. Results: Among them, formulation F3 was identified as the optimized batch, exhibiting highest drug content, %EE, Suitable particle size of in nanorange, acceptable stable PDI, zeta potential of −26.7 mV, and 93.85±0.66% cumulative % in-vitro drug release after 8 h. Statistical optimization using Response Surface Methodology (RSM) and ANOVA confirmed the significant influence of formulation variables on the response parameters. The optimized formulation followed zero-order release kinetics, indicating sustained drug release, while FESEM analysis confirmed successful nanoparticle formation. Conclusions: In conclusion, the developed SLNs significantly improved the pharmaceutical characteristics of Nimodipine and demonstrated their potential as an effective carrier system for enhancing its solubility, controlled release, and oral bioavailability and might be the potential carrier to manage cerebrovascular disorders in future.