Solid lipid nanoparticle-based approaches for improving the bioavailability of low-solubility drugs: a detailed review

Doi: https://doi.org/10.55522/ijti.v4i2.0143

Abstract

Poor aqueous solubility continues to be a critical barrier in the development of effective oral drug delivery systems, particularly for compounds classified under BCS Class II and IV. Although these molecules possess strong therapeutic promise, their clinical performance is often compromised by inadequate dissolution, restricted gastrointestinal absorption, and extensive first-pass metabolism. Solid lipid nanoparticles (SLNs) have gained considerable attention as an advanced nanocarrier platform capable of overcoming these limitations by improving drug solubilization, stabilizing chemically sensitive molecules, enhancing membrane permeability, and enabling controlled or site-specific release.

This review provides a comprehensive overview of the fundamental concepts underlying SLN technology, including formulation principles, key preparation methods, and current characterization techniques. In addition, recent therapeutic applications of SLNs for enhancing the bioavailability of poorly soluble drugs are critically examined. The discussion also addresses existing challenges such as stability issues, drug expulsion, and scale-up complexities, along with potential safety considerations. Emerging innovations—such as targeted SLN systems, hybrid lipid matrices, and the integration of artificial intelligence in formulation design—are highlighted as promising directions for future development. Overall, SLNs represent a biocompatible and versatile nanotechnology platform with substantial potential to improve the clinical translation of poorly water-soluble therapeutic agents.