Solid lipid nanoparticles as insulin inhalation carriers for enhanced pulmonary delivery

Area of Science:

• Pharmacology
• Drug Delivery
• Nanotechnology

Background:

• Pulmonary drug delivery offers advantages for systemic administration of peptides like insulin, including rapid action and reduced side effects.
• Sustained-release formulations for pulmonary insulin delivery remain underexplored.
• Solid lipid nanoparticles (SLNs) present a promising carrier system for enhanced drug stability and controlled release.

Purpose of the Study:

• To develop and characterize a novel dry powder inhalation (DPI) system for pulmonary delivery of insulin-loaded solid lipid nanoparticles (Ins-SLNs).
• To evaluate the stability, inhalation properties, and in vivo hypoglycemic efficacy of the Ins-SLNs DPI formulation.

Main Methods:

• Insulin was encapsulated into lipid carriers to achieve high entrapment efficiency.
• A DPI formulation was prepared using spray freeze-drying of the Ins-SLNs suspension with optimized parameters.
• Particle properties were analyzed for pulmonary delivery potential.
• In vivo studies were conducted using intratracheal instillation in diabetic rats.

Main Results:

• Insulin-loaded SLNs achieved a maximum entrapment efficiency of 69.47%.
• The developed DPI particles exhibited suitable properties for pulmonary delivery.
• Intratracheal instillation of Ins-SLNs in diabetic rats resulted in a prolonged hypoglycemic effect.
• A relative pharmacological bioavailability of 44.40% was observed at an 8 IU/kg dosage.

Conclusions:

• Solid lipid nanoparticles are effective carriers for pulmonary insulin delivery.
• The developed Ins-SLNs DPI system offers a promising non-injectable approach for sustained insulin release.
• This technology has potential for improved diabetes management through enhanced pulmonary drug delivery.