Studies on Preparation and Characterization of Polyelectrolyte Complex of Gum Kondagogu and Chitosan: pH-Induced Changes in Swelling, Stability and Bound Water Content

Abstract

The objective of the present study was to prepare, optimize and characterize the polyelectrolyte complex of gum kondagogu and chitosan. The maximum yield of the complex was obtained at 10:1 weight ratio of gum kondagogu to chitosan at pH 5.0. The pH dependent swelling studies indicated that polyelectrolyte complex has a highest swelling index at acidic pH. The bound water content study showed the presence of highest bound water at acidic pH and it was attributed to the suboptimal interactions between −NH⁺ ₃ of chitosan and −COO⁻ of gum kondagogu groups, and the same was confirmed by FTIR spectroscopy studies.

Keywords:

• Bound water content
• Chitosan
• Gum kondagogu
• Polyelectrolytes

Notes

*SD: Standard deviation, the yield of the complex was determined in the range of pH conditions from 1.2 to 6.0. Each data point represents the mean ± standard deviation (n = 3).

*SD: Standard deviation, swelling index and bound water content data for polyelectrolyte complex in the range of pH from 1.2 to 8.0. The samples were equilibrated for 24 h at 37°C. Each data point represents the mean ± standard deviation (n = 3).