Keywords: Hydrogel; gellan gum; seaweed; fertilizer

Abstract

The agricultural sector contributes significantly to the economy as it provides a source of food, as well as income and employment. Excessive usage of chemicals in this sector brings harm to both humans and the environment. For the purpose of formulating an environmentally friendly controlled release fertilizer, gellan gum hydrogel was selected as a host to be loaded with a species of seaweed, a natural fertilizer. The objective of this study was to develop a novel seaweed-based fertilizer hydrogel bead. GG-hydrogel beads (GG-B) loaded with seaweed (GG-SB) at various concentrations from 5% to 20% w/v were successfully prepared. FTIR spectra showed the presence of a combination of functional groups from both the host and the seaweed. Elemental analysis supported the FTIR results, as the carbon content increased in line with the concentration of seaweed loaded. The morphologies of GG-B and GG-SB showed distinct differences. The swelling study of GG-B and GG-SB at pH 7.0 showed increased swelling as the seaweed concentration decreased, however, the degradation study showed otherwise. It is hoped that the GG-SB material can be used in fertilizer production as it is safe for both people and the environment.