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Zwitterionic chitosan derivatives for pH-sensitive stealth coating.

ABSTRACT: Zwitterionic chitosan, a chitosan derivative with a unique pH-dependent charge profile, was employed to create a stealth coating on the cationic surface of drug carriers. Zwitterionic chitosans were synthesized by amidation of chitosan with succinic anhydride. The succinic anhydride-conjugated chitosan had an isoelectric point, which could be easily tuned from pH 4.9 to 7.1 and showed opposite charges below and above the isoelectric point. The succinic anhydride-conjugated chitosan was able to inhibit the protein adsorption to the cationic surface at physiological pH, compatible with blood components and well tolerated upon intraperitoneal injection. The succinic anhydride-conjugated chitosan has the potential to serve as a coating material to prevent protein adsorption to cationic surfaces, which can be removed in a pH-responsive manner.

SUBMITTER: Xu P

PROVIDER: S-EPMC2941802 | biostudies-other | 2010 Sep

REPOSITORIES: biostudies-other

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Zwitterionic chitosan derivatives for pH-sensitive stealth coating.

Xu Peisheng P Bajaj Gaurav G Shugg Tyler T Van Alstine William G WG Yeo Yoon Y

Biomacromolecules 20100901 9

Zwitterionic chitosan, a chitosan derivative with a unique pH-dependent charge profile, was employed to create a stealth coating on the cationic surface of drug carriers. Zwitterionic chitosans were synthesized by amidation of chitosan with succinic anhydride. The succinic anhydride-conjugated chitosan had an isoelectric point, which could be easily tuned from pH 4.9 to 7.1 and showed opposite charges below and above the isoelectric point. The succinic anhydride-conjugated chitosan was able to i ...[more]

PMID: 20695636

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