Solid lipid nanoparticles formed by solvent-in-water emulsion-diffusion technique: development and influence on...

Area of Science:

• Pharmaceutical Sciences
• Nanotechnology
• Drug Delivery

Background:

• Developing effective oral insulin delivery systems remains a significant challenge in diabetes management.
• Traditional insulin formulations often require injection due to poor oral bioavailability.
• Solid lipid nanoparticles (SLN) offer a potential platform for encapsulating and protecting therapeutic molecules.

Purpose of the Study:

• To develop and characterize insulin-loaded solid lipid nanoparticles (SLN) using a novel solvent-in-water emulsion-diffusion technique.
• To evaluate the encapsulation efficiency, stability, and biological activity of insulin within the SLN.
• To assess the potential of these SLN as a viable system for oral insulin delivery.

Main Methods:

• Insulin-loaded SLN were prepared using isovaleric acid (IVA), glyceryl mono-stearate (GMS), soy lecithin, and sodium taurodeoxycholate (TDC).
• The solvent-in-water emulsion-diffusion method was employed, followed by simple water dilution to form spherical SLN.
• Encapsulation efficiency, insulin integrity (chemical modification), stability against trypsin, and in vivo hypoglycemic activity in rats were assessed.

Main Results:

• Spherical insulin-loaded SLN were successfully produced with good encapsulation efficiency.
• Insulin remained chemically unmodified and stable after incubation with trypsin.
• Subcutaneous administration of insulin extracted from SLN demonstrated comparable blood glucose-lowering effects to conventional insulin suspension in rats.

Conclusions:

• The developed SLN system effectively encapsulates insulin, preserving its structural integrity and biological function.
• The production process did not compromise insulin's hypoglycemic activity.
• Insulin-loaded SLN present a promising strategy for developing oral insulin formulations.