Solid Lipid Nanoparticles (SLNs) as Carriers for Lipophilic Drugs: A Brief Perspective

Abstract

Solid lipid nanoparticles (SLNs) have emerged as a promising drug delivery system for lipophilic drugs, offering advantages such as improved bioavailability, controlled release, and enhanced stability. SLNs are composed of solid lipids stabilized by surfactants, creating a biocompatible and biodegradable matrix suitable for encapsulating hydrophobic drugs. Compared to conventional delivery systems, SLNs protect drugs from degradation, reduce systemic toxicity, and enable targeted delivery. Various lipid-based formulations, including glyceryl monostearate, stearic acid, and tripalmitin, have been explored to optimize drug loading and release profiles. Additionally, SLNs can be engineered with surface modifications to improve pharmacokinetics and cellular uptake. The development of SLNs faces challenges such as drug expulsion during storage, limited loading capacity, and potential stability issues. However, advancements in formulation techniques, including high-pressure homogenization and solvent evaporation methods, have improved SLN properties, making them viable for clinical applications. Several studies have demonstrated the efficacy of SLNs in delivering lipophilic drugs for cancer therapy, neurodegenerative disorders, and infectious diseases. Their ability to cross biological barriers, such as the blood-brain barrier, further expands their therapeutic potential. This review provides a concise overview of SLNs as carriers for lipophilic drugs, highlighting their advantages, formulation strategies, challenges, and recent advancements. Future research should focus on enhancing drug loading efficiency, ensuring long-term stability, and exploring novel lipid compositions to optimize SLN performance.