重力场流分离系统用于聚苯乙烯颗粒的分离条件优化

重力场流分离是最简单的场流分离(gravitational flow-field fractionation,GrFFF)技术,常用于分离粒径几微米到几十微米的颗粒及生物样品。利用自组装加工的重力场流分离仪器分离3种不同粒径(3、6、20μm)的聚苯乙烯(PS)颗粒。自制了一种混合表面活性剂,并与商品化的表面活性剂FL-70进行了比较。通过均匀设计优化流速、混合表面活性剂中聚乙二醇辛基苯基醚(Triton X-100)的质量分数、载液黏度、停流时间等分离条件,以分离度(Rs)和保留比(R)为评价指标,发现FL-70的分离效能略优于自制的混合表面活性剂,可实现3种PS颗粒的完全分离(Rs1为1.771,Rs2为2.074)。结果表明该系统具有良好的分离性能。

Optimization of experimental conditions for the separation of polystyrene particles by gravitational field-flow fractionation

Gravitational flow-field fractionation (GrFFF) is the simplest and cheapest field-flow fractionation technique. GrFFF utilizes earth's gravity as external field, providing a size-based separation. It can be applied to the separation and characterization of various micrometer-sized particles and biological samples. A GrFFF device was assembled, and three kinds of polystyrene (PS) particles with different sizes (20, 6 and 3 μm) were used as the model particles. A homemade mixed surfactant was used and was compared with the surfactant FL-70. The separation conditions of GrFFF were optimized with uniform design, including flow rate, mass percentage of polyethylene glycol octylphenol ether (Triton X-100) in mixed surfactant, viscosity of carrier liquid and stop-flow time. The resolution (R_s) and retention ratio (R) were utilized as the evaluation indexes. The results suggest that the separation performance of FL-70 was slightly better than that of the mixed surfactant. Using FL-70 as the surfactant, particles of 20, 6 and 3 μm were completely separated (with resolutions of 1.771 and 2.074). The results indicate that this system has good separation performance.