ABSTRACT
In the pharmaceutical field, many kinds of macromolecules have been used to control drug behavior in various dosage forms. Chitin, chitosan, and their derivatives are utilized for these drug delivery systems. Antitumor drugs are selected as agents to be controlled by the drug delivery systems because they exhibit toxic effects as well as therapeutic effects in many cases. Chitosan, chitin, or chitosan derivative-drug conjugates may be developed as to therapeutic antitumor agents or strong bioactive agents. N-Succinyl-chitosan and 6-O-carboxymethyl-chitin are water-soluble chitosan and chitin derivatives, respectively. The remaining amino groups and carboxyl groups in Suc-chitosan were considered to be combined together by carbodiimide coupling and consequently to form cross-linking, whereas for CM-chitin, such cross-linking would occur to a small extent because of few amino groups. The in vivo release rates from CM-chitin-Mitomycin C (MMC) and Suc-chitosan-MMC were consistent with the in vitro drug release rates.
