Characteristic Analysis of Chitosan Thermo-Hydrogels:Molecular Weight Dependent Chitosan/β-glycerophosphate Hydrogel

Abstract

Chitosan (CTSN) and β-glycerophosphate (GP) based hydrogels were prepared and characterized to elucidate the chemical interactions involved in the formation of these hydrogels depending upon the molecular weight of chitosan. Characterization of nanostructure of the resulting hydrogels was investigated by Fourier Transform-Infrared Spectroscopy (FT-IR). We observed that the major interaction which might be responsible for the formation of these hydrogels is between phosphate groups (PO43-) of GP and amine groups of chitosan. Whereas, the addition of hyaluronic acid (HA) which may act as a crosslinker has a negative effect on available free phosphate groups in the hydrogel confirmed by FT-IR analysis (971.9 cm-1 peak). Decisively, the outcomes of spectrophotometric analysis also coincide with the findings of FT-IR for the CTSN/GP/HA thermo-hydrogel system. This study demonstrates the standard protocol to provide a practical approach for the analysis of interactions involved in the formation of CTSN/GP/HA hydrogels that could be potently useful in pharmacological and pharmaceutical applications.