Preparation of chitosan gel
A method described by Nomanbhay and Palanisamy [7] was
employed. A 50 g of chitosan was slowly added to 1 L of 10 wt%
oxalic acid with constant stirring. The mixture was heated to
40–50 ◦C to facilitate mixing. The chitosan was allowed to cool
at room temperature and a whitish viscous gel of chitosan–oxalic
acid mixture was obtained