| Abstract Scope |
Poor aqueous solubility remains one of the major obstacles in oral drug development, with approximately 40% of marketed drugs and nearly 90% of drug candidates exhibiting limited water solubility. These compounds often demonstrate low dissolution rates, poor intestinal permeability, extensive first-pass metabolism, and consequently inadequate oral bioavailability. Lipid-based nanocarriers have emerged as one of the most successful formulation strategies to overcome these limitations by improving drug solubilization, protecting drugs from gastrointestinal degradation, promoting intestinal lymphatic transport, and enhancing epithelial permeation. Recent advances in formulation engineering have expanded the application of solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), nanoemulsions, self-nanoemulsifying drug delivery systems (SNEDDS), and lipid nanocapsules for oral delivery of Biopharmaceutical Classification System (BCS) Class II and IV drugs. This mini-review critically discusses recent progress in lipid-based nanocarriers, emphasizing formulation characteristics, mechanisms underlying enhanced oral bioavailability, recent pharmaceutical applications, and current translational challenges. Particular attention is given to recent experimental studies that establish formulation–performance relationships for clinically relevant poorly water-soluble drugs. |