Synthesis of an O-alkynyl-chitosan and its chemoselective conjugation with a PEG-like amino-azide through click chemistry

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Jose Ricardo Oliveira (Author) Other; Cristina C L Martins (Author) Other; Luis Mafra (Author) Other; Paula Comes (Author) FCUP

Journal

Title: Carbohydrate Polymers

Vol. 87

Pages: 240-249

ISSN: 0144-8617

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 86 Citations

Scopus - 89 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-002-DZK

DOI: 10.1016/j.carbpol.2011.07.043

Abstract (EN): N-Phthaloyl-chitosan O-prop-2-ynyl carbamate was prepared as a biopolymer amenable to undergo chemoselective conjugation by azide-alkyne coupling, while allowing upturn of chitosan's amines after dephthaloylation. N-phthaloylchitosan was prepared according to previously described methods and, due to its low solubility in current organic media, subsequent modifications were run in heterogeneous conditions. Activation of hydroxyls with carbonyl-1,1 '-diimidazole and coupling to propargylamine yielded N-phthaloyl-chitosan O-prop-2-ynyl carbamate, then coupled to a model PEG-like azide by azide-alkyne coupling, giving the expected triazolyl conjugate. N-Dephthaloylation allowed recovery of the free amines, responsible for chitosan's bioadhesion and tissue-regeneration properties. The structures of all polymers were confirmed by Fourier-transformed infra-red (FT-IR) and X-ray photoelectron (XPS) spectroscopies, as well as by solid-state nuclear magnetic resonance (SSNMR). All chitosan derivatives were poorly soluble in both aqueous and organic media, which makes them suitable for topical applications or for removal of toxic substances from either the gastric intestinal tract or environmental sources.

Language: English

Type (Professor's evaluation): Scientific