关键词: 静电液滴发生器, 海藻酸盐, 微球, 粒径, 理论计算

Abstract: Gel microspheres of calcium alginate and alginate-polycation microcapsules are widely used as the mobilization of biology, controlled release of drug and biologic adsorbents. In this paper, gel microspheres of calcium alginate are prepared through electrostatic droplet generator and formula of theoretical calculation of diameter of gel microspheres is accordingly given under different conditions. The results of theoretical calculation show that diameter of gel microspheres is determined by the voltage, distance between positive pole and negative pole, inner diameter of needle, flow rates of syringe pump and physicochemical properties of alginate. The diameter of gel microspheres will decrease with increasing voltage and decreasing the distance between electrode and it has the lowest value, which is defined as the critical diameter of gel microspheres and is in a direct proportion to the inner diameter of needle. The uniform gel microspheres with different diameters are prepared through changing physicochemical properties of alginate and parameters of electrostatic droplet generator. In order to obtain good spherical and homogeneous beads, the optimum mass concentration range of sodium alginate is from 0.15 to 0.20 g/L. The experimental results match the theoretical calculation well. The formula of theoretical calculation can be widely used to study the effect of physicochemical properties of alginate and parameters of electrostatic droplet generator on the diameter of gel microspheres of calcium alginate.

Key words: Electrostatic droplet generator, Alginate, Microspheres, Diameter of get microsphere, Theoretical calculation