Controlled release of urea using negatively charged polysaccharides

The current study aims to synthesize cross-linked alginate-gum arabic, a polysaccharide biopolymer composite, to evaluate its efficacy for the controlled release of urea. The alginate-gum arabic solution was prepared in a 2:1 ratio, and urea was entrapped in three different amounts: 50 mg for SG1, 100 mg for SG2, and 150 mg for SG3. CaCl2 used as the crosslinker, and the urea-entrapped alginate-gum arabic hydrogel beads were produced using ionotropic gelation method. Produced beads were underwent physical evaluation to analyze their size, porosity, and swelling behavior. The highest diameter was exhibited in SG3 at 3.60 +/- 0.01 mm. Additionally, the highest porosity was observed in SG3 beads, measuring 63.6% +/- 0.33%. The release of urea was quantified using the DiacetylMonoxim (DAM)-UV visible spectroscopy method. Further, the characterization of the produced hydrogel beads was analyzed using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analyses (TGA). FTIR revealed the characteristic band at 3770 and 2355 cm-1, indicating the presence of urea entrapped in alginate-gum arabic beads. TGA analyses indicates that the good thermal stability of the produced beads.