Formulation and evaluation of hyaluronic acid-based mucoadhesive self nanoemulsifying drug delivery system (SNEDDS) of tamoxifen for targeting breast cancer.

The present study was intended to develop a papain grafted S-protected hyaluronic acid-lithocholic acid co-block (PAP-HA-ss-LCA) polymeric excipient as an amphiphilic muco permeating stabilizer for targeting breast cancer epithelial cells overexpressed with CD44 receptors. The mucopermeating, stabilizing and targeting capability of the PAP-HA-ss-LCA polymeric excipient was investigated by manufacturing tamoxifen (TMX) loaded self-nanoemulsifying drug delivery system (SNEDDS). TMX loaded PAP-HA-ss-LCA incorporated SNEDDS (TMX-PAP-HA-ss-LCA SNEDDS) were characterized for their surface chemistry, drug release, permeation enhancement, biocompatibility and antitumor activity. FTIR spectroscopic analysis showed successful synthesis of PAP-HA-ss-LCA polymer. X-ray diffraction (XRD) showed the amorphous form of TMX inside SNEDDS. The observed hydrodynamic diameter of TMX-PAP-HA-ss-LCA SNEDDS was 367.5 nm. Furthermore, Hyaluronic Acid-based Mucoadhesive Self Nanoemulsifying Drug Delivery System (SNEDDS) of TMX showed homogeneity in synthesis with low polydispersity and negative zeta potential due to stabilization with PAP-HA-ss-LCA polymer. The distinct spherical shape of the nanodroplets was evident by transmission electron microscopy (TEM). In vitro release kinetics indicated approximately >80% release within 48 h under sink conditions. Ex-vivo permeation study displayed 7.11-folds higher permeation of TMX by TMX-PAP-HA-ss-LCA in contrast to pure TMX. The biocompatibility study proved that SNEDDS formulation was safe and compatible against macrophages. In vitro cytotoxicity studies demonstrated that TMX-PAP-HA-ss-LCA SNEDDS could efficiently kill MCF-7 breast cancer cells as compared to the native TMX drug. Systemic toxicity studies proved the non-toxic nature of TMX-PAP-HA-ss-LCA in contrast to pure TMX. Based on these evidences, TMX-PAP-HA-ss-LCA SNEDDS formulation seems to be promising mucopermeating, augmented intracellular uptake with strong targeting potential for anti-proliferative activity.