1. The rheological injectability of N-succinyl-chitosan solutions.
- Author
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Rogalsky, Allan, Kwon, Hyock Ju, and Lee-Sullivan, Pearl
- Subjects
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RHEOLOGY , *CHITOSAN , *SOLUTION (Chemistry) , *VISCOSITY , *IONIC strength , *NUCLEAR magnetic resonance spectroscopy - Abstract
The viscosity of a set of N-succinyl-chitosan (NSC) solutions was characterized near the 0.2 Pa s rheological injectability limit. This is believed to be the first such report in the open literature. Viscosity was characterized at physiological pH and ionic strength as a function of NSC degree of substitution, NSC concentration, temperature, and shear rate. NSC was synthesized via Yamaguci's method and characterized using H-NMR, membrane osmometry, TGA and isothermal vacuum drying. NSC synthesis results were shown to fit a reproducible log-linear correlation and both optimum drying temperature and thermal decomposition temperature were found to be a function of NSC degree of substitution. Viscosity results were explained using Katchalsky's full model for polyampholyte ionization combined with a charge induced excluded volume model proposed by Higgs. The model predicted a polyelectrolyte/polyampholyte transition which agreed well with experimental data. For minimally injectable formulations a maximum in primary amine concentration is expected at 32 sub% amine NSC. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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