Solid lipid nanoparticles based dry powder inhalers for enhanced drug delivery against lung diseases

The global incidence of lung diseases associated with high mortality and morbidity rates is projected to rise in the coming years. Conventional therapies face limitations such as low bioavailability and systemic side effects with oral administration, as well as poor patient compliance and frequent dosing with traditional inhalers. These shortcomings have created an urgent need for novel pulmonary drug delivery systems. In recent years, nanoparticulate drug carriers have gained significance for their potential to enable targeted lung delivery and reduced dosing frequency. Among them, solid lipid nanoparticles (SLNs) have attracted considerable attention due to their biocompatible and biodegradable structures, controlled release capabilities, organic solvent-free production processes and favorable aerodynamic behavior. This review provides a comprehensive per spective to guide the rational design of SLN-based dry powder inhaler (DPI) systems by integrating formulation strategies, production techniques, surface functionalization, and DPI development, with the goal of enhancing therapeutic outcomes in respiratory diseases such as cancer, infections, chronic obstructive pulmonary disease, and cystic fibrosis.