Design, characterization and in vitro evaluation of SMEDDS containing an anticancer peptide, linear LyP-1

LyP-1 (CGNKRTRGC) is a nine amino acid peptide that shows high specificity for tumor lymphatics. The aim of this study was to develop lipid-based formulations containing the linear form of LyP-1 for lymphatic targeting. Self-microemulsifying drug delivery systems (SMEDDS) were designed for the delivery of linear LyP-1 by itself and as a solid dispersion (SD). Formulations were characterized in terms of physical stability, pH, morphological properties, droplet size distribution and zeta potential. Thermodynamically stable microemulsions were obtained with an average droplet size around 20 nm and zeta potential near neutrality. Cytotoxicity studies of blank and peptide-containing SMEDDS were carried out on Caco-2 cell line. Bioactivity studies of peptide-containing formulations were carried out on MDA-MB-231 breast cancer cell line. It was shown that blank and peptide-containing SMEDDS formulations were not cytotoxic to Caco-2 cell line. However, formulations containing the peptide and peptide SD led to a significant decrease in cell viability on breast cancer cells. It could be concluded that the SMEDDS formulations containing the linear LyP-1 were successfully developed for the lymphatic targeting of solid tumors in vitro.