Silk-fibroin-coated liposomes for long-term and targeted drug delivery
Authors Andrea S Gobin, Robyn Rhea, Robert A Newman, Anshu B Mathur
Published 15 March 2006 Volume 2006:1(1) Pages 81—87
Andrea S Gobin1, Robyn Rhea2, Robert A Newman2, Anshu B Mathur1
1University of Texas MD Anderson, Cancer Center, Laboratory of
Reparative Biology and Bioengineering, Plastic Surgery, Houston, TX, USA; 2Pharmaceutical Development Center, Houston, TX 77054, USA
Abstract: Many barriers to drug delivery into a tumor site require careful consideration when designing a new drug. In this study, the adhesive targeting and drug specificity of modified liposomal vesicles on human-scar-producing cells, keloid fibroblasts, were investigated. Keloids express abundant levels of mucopolysaccharides and receptor tyrosine kinase (RTK). In this report, the structural properties, drug release kinetics, and therapeutic availability of silkfibroin- coated, emodin-loaded liposomes (SF-ELP), compared with uncoated, emodin-loaded liposomes (ELP), were investigated. SF-ELP had a highly organized lamellae structure, which contributed to 55% of the liposomal diameter. This modified liposomal structure decreased emodin release rates by changing the release kinetics from a swelling and diffusional process to a purely diffusional process, probably due to steric hindrance. SF-ELP also increased adhesion targeting to keloid fibroblasts. Increased retention of SF-ELP is most likely due to the interaction of the fibrous protein coating around the ELP with the pericellular molecules around the cell. SF-ELP also decreased survival rate of keloids that expressed high levels of RTK. These results demonstrated that SF-ELP enhanced emodin delivery by improved diffusion kinetics and specific cell targeting.
Keywords: silk fibroin, liposomes, emodin, keloids, cell targeting