Formulation of Thermosensitive Hydrogel Containing Cyclodextrin for Controlled Drug Delivery of Camptothecin

Purpose: To formulate and evaluate temperature-sensitive, controlled-release camptothecin hydrogel for anticancer drug delivery.
Method: Temperature-sensitive hydrogel based on chitosan/β-glycerophosphate (β-GP)/β-cyclodextrin (β-CD) was prepared by crosslinking method. The formulations were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), gelation time, and viscometry, as well as for controlled release. The formulation, containing camptothecin, was studied by MTT assay on tumor cell MCF-7. The effectiveness of treatment was measured in terms of controlled tumor growth inhibition (TGI).
Results: The hydrogel formulation showed good properties in terms of pH, gelation, viscosity and in- vitro release. The gelation temperature and viscosity of the formulation was optimum. Camptothecin (CPT) released from the hydrogel (TF8) over 8 h in pH 7.4 buffer ranged from 38.97 - 92.5 %, and varied according to the composition of the hydrogels. Release of camptothecin was lowest from preparations without cyclodextrins. Tumor growth inhibition activity of CPT in MCF-7 cell was highest for the formulation containing 1 % chitosan, 8 % β-GP and 1 % β-CD while no inhibition was observed for the blank temperature sensitive hydrogel formulation.
Conclusion: These formulations are a promising and more effective delivery system that can be developed to serve as an alternative to the conventional system for anticancer drug delivery.

Keywords
Hydrogel; Chitosan; β-Glycerophosphate; β-Cyclodextrin; Camptothecin; MCF-7 cell line