N-acylated chitosan: hydrophobic matrices for controlled drug release
N-acylated chitosan: hydrophobic matrices for controlled drug release
- Journal of Controlled Release, 93(1), p.1-13, 2003 .
N-acylation of chitosan with various fatty acid (C6-C16)chlorides increased its hydrophobic character and made important changes in its structural features. Unmodified chitosan exhibited a low degree of order (DO)and a weak tablet crushing strength. Chitosan acylated with a short chain length (C6)possessed similar properties, but exhibited significant swelling. Acylation with longer side chains (C8-C16)resulted in a higher DO and crushing strength but lower swelling. The best mechanical characteristics and drug release properties were found for palmitoyl chitosan (substitution degree 40-50
CHITOSAN
N-ACYLATION
HYDROPHOBIC SELF-ASSEMBLING
PALMITOYL CHITOSAN
CONTROLLED RELEASE
N-acylation of chitosan with various fatty acid (C6-C16)chlorides increased its hydrophobic character and made important changes in its structural features. Unmodified chitosan exhibited a low degree of order (DO)and a weak tablet crushing strength. Chitosan acylated with a short chain length (C6)possessed similar properties, but exhibited significant swelling. Acylation with longer side chains (C8-C16)resulted in a higher DO and crushing strength but lower swelling. The best mechanical characteristics and drug release properties were found for palmitoyl chitosan (substitution degree 40-50
CHITOSAN
N-ACYLATION
HYDROPHOBIC SELF-ASSEMBLING
PALMITOYL CHITOSAN
CONTROLLED RELEASE