“海藻酸－鈣＂－凝膠球粒成型機制及影響性探討

Sodium alginate is a type of hydrophilic polymer and shows a translucent homogeneous viscous colloidal solution when dissolved in water. After binding with the calcium ions, insoluble calcium-alginate hydrogel will be formed. It can be used as a membrane-forming raw material in the microencapsulation technology which is often used in pharmaceuticals and food industries. In this study, the microencapsulation coacervation method was used to prepare the hydrogel beads and the control factors, such as concentration of sodium alginate, concentration of calcium chloride, air-flow rate and curing time were manipulated to study the forming mechanisms and effects of these factors on the formation of the calcium-alginate hydrogel beads. The results showed that when the hydrogel beads were prepared at appropriate extension of the curing time (60-120 min), and increased concentration of sodium alginate (3-5%) and calcium chloride (0.3-0.5 M), complete particles with smooth spherical appearance will be produced. The size of the hydrogel beads could be effectively controlled through the adjustment of air-flow speed. However, high air pressures would cause irregular shapes. The differential scanning calorimetry indicated that appropriate curing time could enhance the binding strength of the sodium alginate and calcium ions. From the fourier transform infrared spectroscopy (FT-IR) results, it was found that 1590～1750 cm^(-1) belonging to the conjugated structure of the C＝O functional group is the peak position that affects the binding effect.