Cross-linked guar gum and sodium borate based microspheres as colon-targeted anticancer drug delivery systems for 5-fluorouracil.

The aim was to prepare cross linked polymer of 5-fluorouracil loaded microspheres containing guar gum and sodium borate for colon-targeted drug delivery systems. Micro spheres were prepared using emulsification cross linking method. The influence of drug polymer ratio, cross linker agent concentrations and cross linking timing on in vitro drug release and characteristics in terms of drug loading, entrapment efficiency and yielding percentage were investigated. The optimum drug loading, entrapment efficiency and percent yield were obtained from formulations with the lowest content of cross linker agent over 2 h of cross linking timing but with the highest drug to polymer ratio 1:11. The optimum in vitro drug release was obvious upon decreasing drug to polymer ratio up to 1:09, resulting in 81.5% drug release over 24 h. In conclusion, micro spheres composed of gaur gum and sodium borate can delay and control the release of 5-fluorouracil over 24 h. Thus, further in vivo studies are suggested for final assessment.