OPTIMIZATION OF THE FORMULATION AND IN-VITRO EVALUATION OF CAPECITABINE NIOSOMES FOR THE TREATMENT OF COLON CANCER

The goal of the present study was to investigate the feasibility of using non-ionic surfactant vesicles as carriers for the sustained delivery of water soluble anti-cancer drug Capecitabine, used in the treatment of colorectal cancer. The niosomal formulations were prepared using various non-ionic surfactants (span 40, span 60, tween 40 and tween 60) in the presence of cholesterol, by thin film hydration technique. The effect of process related variables like hydration time, sonication time, rotation speed of evaporation flask on the entrapment efficiency and in vitro drug release were evaluated. Formulation of Capecitabine niosomes was optimized by altering the proportions of Tween, Span and cholesterol. The formation, morphology and size of the drug loaded niosomes were determined by optical microscopy, transmission electron microscopy and particle size analyzer respectively. Results showed a substantial change in the release rate and in the % Entrapment of Capecitabine from niosomal formulations upon varying the type of surfactant and cholesterol content. In-vitro drug release results confirmed that the niosomal formulations have exhibited a higher retention of Capecitabine inside the vesicles such that the in-vitro release was slower compared to the drug solution. Highest drug entrapment (59.1 +/- 0.72%) and sustained release (67.95 +/- 0.65%) was obtained with vesicles formed using tween 60 and cholesterol in 4: 1 ratio. The optimized niosomal formulation was subjected to stability studies at 4 +/- 2 degrees C and 27 +/- 2 degrees C for a period of three months.