RESUMEN
Aim: To develop a new preparation consisting of colon adhesive pellets of sodium 4-amino salicylate for the treatment of ulcerative colitis, and to characterize the adhesive of the prepared pellets. Methods: Centrifu-gation-granulation was used to prepare sodium 4-amino salicylate pellets into which HPMC K4M and Carbomer 934P as matrix were incorporated. The pellets were coated with Surlease~((R)), and filled into enteric-coated cap-sules. The release of sodium 4-amino salicylate from the pellets was evaluated in the pH 7. 4 buffer. The adhesive property of the pellets was characterized by evaluating the transit rate of the pellets in the rat intestine in vivo, and by determing the remaining( %) of the pellets in the isolated rat colonic segment in vitro. The adhesive of the pel-lets in vivo was also verified by X-rays. Results: It was shown that the resultant pellets of round shape, good uni-formity in size, and favorable rigidity possessed the colon-adhesive and sustained-release properties. Conclusion:The simple, economical and practical approach was sucessfully utilized in the preparation of sodium 4-amino sa-licylate pellets with the remarked colonic adhesion and targeting.