Synthesis and Physicochemical and Dynamic Mechanical Properties of a Water-Soluble Chitosan Derivative as a Biomaterial

Abstract

The physicochemical and rheological properties of a water-soluble chitosan (WSC) derivative were characterized in order to facilitate its use as a novel material for biomedical applications. The WSC was prepared by conjugating glycidyltrimethylammonium chloride (GTMAC) onto chitosan chains. Varying the molar ratio of GTMAC to chitosan from 3:1 to 6:1 produced WSCs with a degree of substitution (DS) that ranged from 56% to 74%. The WSC with the highest DS was soluble in water up to concentrations of 25 g/dL at room temperature. An increase in the polymer concentration gradually increased both the pH and conductivity of the WSC solutions. The rheological properties of the WSC solutions were found to be dependent on the salt and polymer concentrations as well as the DS value. In the absence of salt, the rheological behavior of the WSC was found to be typical of that for a polyelectrolyte in the dilute solution regime. However, the addition of salt decreased the viscosity of the polymer solution due to the reduction of electrostatic repulsions by the positively charged trimethylated ammonium groups of the WSC. In the concentrated regime, the viscosity of the WSCs was found to follow a power-law expression. The lowest DS WSC had the more favorable viscoelastic properties that were attributed to its high molecular weight, as confirmed by the stress relaxation spectra and intrinsic viscosity measurements. The effect of DS on the degree of interaction between WSC and the lipid egg phosphatidylcholine was investigated by FTIR analysis. Overall, the lower DS WSC had enhanced rheological properties and was capable of engaging in stronger intermolecular physical interactions.

Antibacterial and conductive injectable hydrogels based on quaternized chitosan-graft-polyaniline/oxidized dextran for tissue engineering

“…QCS was synthesized according to reference with modification [51]. Briefly, 1 g of chitosan (J&K Chemical, M n =100,000-300,000 Da) was suspended in 36 mL of deionized water, subsequently 180 µL of acetic acid (AcOH) (0.5% v/v) (Sigma-Aldrich) was added to the suspension.…”

“…The purification process was repeated three times, and the purified QCS was dried in a vacuum oven at room temperature for 3 days. The DS of the QCSs was determined by titrating the content of chlorine ion [51]. The samples with different DS were named as QCS20, QCS40 and QCS66, respectively, as listed in Table 1.…”

“…An obvious characteristic peak at about 1475 cm -1 corresponding to the methyl band of GTMAC [51] was present in the spectra of QCS40 and QCS40P4 but not in that of chitosan ( Figure S3). This result revealed that GTMAC was successfully conjugated to the amine group on chitosan backbone.…”

Synthesis of Chitosan Surfactants

“…For this purpose the free amino group was quaternised with methyl iodide or grafted with glycidyltrimethylammonium chloride (GTMAC) to get water-soluble products. [10,11] The same was achieved through grafting of either poly(ethylene glycol) chains or oligosaccharide fragments to the amino function. [12,13] Carboxymethylation, either at C-6 hydroxy group with monochloroacetic acid or selective N-carboxymethylation with glyoxylic acid and NaBH 3 CN by reductive alkylation results in derivatives that are soluble in aqueous alkali.…”

Preparation and characterization of N‐alkylated chitosan derivatives

“…The presence of chitosan amino groups is interesting, and many efforts have been made to improve its solubility in water. Various kinds of modifications have been made to chitosan in recent years, including acylation, 9,10 akylation, 11,12 carboxymethylation, 13,14 and quaternarization. 15 The research has focused on the solubility of chitosan derivatives, 9 and these methods 10,12,16 are complex and luxurious.…”