Solid Lipid Nanoparticles for Sustained Release of siRNAs

Researchers in Dr. Richard Zare's lab have developed solid lipid nanoparticles (SLNPs) that provide sustained in vivo delivery of small interfering RNAs (siRNAs). siRNAs can silence genes responsible for disease, which makes them promising tools for gene therapy. However, in vivo delivery of siRNAs remains challenging due to lack of safe, efficient, and sustained delivery systems. siRNAs are rapidly degraded in the plasma and cellular cytoplasm resulting in short siRNA activity. To overcome these limitations the inventors have created new SLNPs to encapsulate and protect the siRNA and provide sustained in vivo siRNA delivery. In addition to solid lipids, the researchers suggest using lipids extracted from human adipose tissue to form nanoparticles with the aim of providing better biocompatibility.

Illustration shows the in vivo release data of fluorescently labeled siRNA. Left- release data of free (unencapsulated) siRNA. Right- release of siRNA from SLNPs. SLNPs are coated with lipids (orange) and other molecules and contain siRNA (red) in complex with a positively charged lipid (purple).

Stage of Research
The inventors have shown that the SLNPs provide sustained release of siRNA in vivo and in vitro over a period of 10-13 days with retained functionality.