Preparation, Characterization and Study of the Dissociation of Naproxen from Its Chitosan Salt.
Molecules
; 27(18)2022 Sep 07.
Article
em En
| MEDLINE
| ID: mdl-36144537
ABSTRACT
Salts of naproxen (NAP) with chitosan (CTS) and reticulated chitosan (CEP) were prepared under optimized conditions to maximize the yield of reaction. The objective was to evaluate the dissociation in water, which can guide studies of release of the drug from biopolymeric salts in pharmaceutical applications. Higher salification was found after 24 h of reaction at 60 °C in a molar ratio 11.05 (CTSNAP, mol/mol), resulting in a degree of substitution (DS) of 17% according to 13C NMR, after neutralization of the -NH2 group of the biopolymer by the carboxylic group of the drug. The presence of NAP salt is evidenced by FTIR bands related to the -NH3+ group at 856 cm-1, a decrease in crystallinity index in XRD diffractograms as well as changes in mass loss ratios (TG/DTG/DTA) and increased thermal stability of the salt regarding CTS itself. The CEPN crosslinked salt presented a DS = 3.6%, probably due to the shielding of the -NH2 groups. Dissociation studies revealed that at pH 2.00, dissociation occurred faster when compared to at pH 7.00 in the non-reticulated salt, while the opposite was observed for the reticulated one.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Quitosana
Idioma:
En
Revista:
Molecules
Assunto da revista:
BIOLOGIA
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Brasil