Preparation of alginate capsule using two coaxial glass-tube

Abstract

TEMPO-Oxidized bacterial cellulose (TOBC) were obtained using TEMPO-mediated oxidation (TOBC) to produce carboxylate groups on bacterial cellulose surfaces. TOBC had lower crystallinity but better aqueous dispersion than bacterial cellulose. TOBC was used as a reinforcement agent for production alginate capsules. The alginate capsules for entrapping rice bran oil were made via a coaxial-glass tube. The factors that influenced on the shape and production efficiency of capsules were the gap between tube tip and the Ca2+ ions bath and the viscosity of shell solution. However, these factors had no effect on the size and shell thickness of capsules. Increasing of TOBC content enhanced the turbidity and compression strength of shell and gave smoother surface. The TOBC-alginate film was fabricated to easier characterization the shell property. More TOBC content can decrease the shrinkage of films, increase mechanical property and oxygen transmission rate, but had no effect on thermal and water vapor transmission rate. The carboxyl group of TOBC can participate crosslinking with Ca2+ and act as the structural construction of the alginate.