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Colon cancer refers to cancerous growth in colon,rectum or cecum [1].Oral anti-cancer drug has been advocated as adjuvant,neo-adjuvant or primary therapy.A substantial number of research studies have been conducted to design colon-specific or colon cancer cell-specific dosage form with the aim to reduce premature drug loss into the systemic circulation at the upper gastrointestinal tract,and to promote drug accumulation and cellular targeting at the cancer site.Premature drug loss can be circumvented through polymer-drug conjugation in addition to intra-capsular coating or film coating [2,3].Cancer cell specificity is obtainable via covalent tagging of polymer or drug with ligands such as folate.Conjugation of a polymer with both drug and ligand on the same parent chain may incur ligand or drug loss during the synthesis process.As such,this study designs glyoxalated chitosan with 5-fluorouracil drug and folate ligand tagged on different chitosan chains (Fig.1).