Biodegradable sodium alginate and lignosulphonic acid blends: characterization and swelling studies

Abstract

In this article, Sodium alginate and Lignosulphonic acid blends were prepared in different weight ratios by solution casting method. Swelling experiments were conducted for Sodium alginate and its blends by adding calcium chloride for various intervals in a pH 7.4 medium. The strength of the films increases after their treatment with CaCl2 at higher intervals forming an alginate network. The SA/LS blend (80/20) is subjected for sorption studies at variable pH 1.2 & 7.4, in order to test the suitability of the blends for controlled drug delivery. Further, experiments were conducted for de-crosslinking using 0.1M HCl. The solvent uptake for the blends decreased with increasing LS content in the blends. Blends were investigated by X-ray diffraction and Fourier Transform Infra-Red spectroscopy in order to study the crystallinity and molecular interactions. XRD confirms the reduction in cluster space in blends leading to lower uptake of solvent.

Keywords

• Sodium alginate
• blends
• swelling
• biomaterials
• water soluble polymers
• crosslinking