拖尾型海藻酸钙凝胶微球可控制备

Controlled Preparation of Tailed-Type Calcium Alginate Gel Microspheres

本文用一种简单的微流控装置在共轴注入条件下制备了大尺寸的海藻酸钠微球。该装置由PDMS铸造而成,模具由小直径金属和聚四氟乙烯管组成。在硅油中通过该装置生成2%海藻酸钠的液滴,然后在2% CaCl2溶液中交联,该溶液以0.1%~1.5% (w/v)的浓度混合羟丙基甲基纤维素。结果表明,产生的海藻酸钠微球的形态取决于羟丙基甲基纤维素的浓度。随着羟丙基甲基纤维素浓度的增加,由于油与交联溶液界面张力的降低,海藻酸钠微球的形状从半球形到尾球形。浓度越高,形成的海藻酸钠微球的尾部愈发尖锐。这些不同形状的海藻酸钠微球对纳米生物医学、生物医用材料等方面的应用有很重要的作用。

Large size sodium alginate microspheres were prepared by a simple microfluidic device under coaxial injection condition. The device is cast from PDMS and the mold consists of small diameter metal and PTFE tubes. Droplet of 2% sodium alginate was generated by the device in silicone oil and then cross-linked in a solution of 2% CaCl2, which was mixed with hydroxypropyl cellulose at a concentration of 0.1% to 1.5% (w/v). Our results show that the morphology of the resulting sodium alginate microspheres is strongly dependent on the concentration of hydroxypropyl cellulose. With the increase of hydroxyl propyl cellulose concentration, the shape of sodium alginate microspheres changed from hemispherical to tail-shaped due to the decrease of interfacial tension between oil and cross-linked solution. The higher the concentration, the sharper the tail of the sodium alginate microspheres. These different shapes of sodium alginate microspheres play an important role in the application of nanomedicine and biomedical materials.