表面图案化磁性复合微球的原位制备与表征

采用反相悬浮聚合法合成了丙烯酸(AA)含量不同的N-异丙基丙烯酰胺-丙烯酸共聚物P(NIPAM-co-AA)微凝胶, 并以其作为微反应器, 通过原位外源沉积法制备了一系列微米级、表面具有图案化结构的SiO₂-Fe₃O₄-P(NIPAM-co-AA)磁性复合微球. 实验结果表明, 复合微球的表面结构与微凝胶的组成、Fe₃O₄和SiO₂的沉积量有关. 在微球表面进行修饰, 可得到表面带有氨基等官能基团的磁性复合材料. 将这种功能化磁性微球用于识别生物大分子并进一步用于生物医学领域具有重要的意义.

Magnetic Composite Microspheres with Patterned Surface Structures: Preparation in situ and Characterization

N-isopropylacrylamide (NIPAM) and acrylic acid (AA) copolymer microspheres with various compositions were prepared by a reverse suspension polymerization technique. The microspheres thus pre- pared were employed as micro-reactors for the synthesis of Fe3O4 and the deposition of SiO2 in situ. In this way, several kinds of SiO2-Fe3O4-P(NIPAM-co-AA) magnetic composite microspheres with different sur- face morphologies were prepared. It was demonstrated that the surface structures of the composite micro- spheres could be tailored to a certain extent by varying the ratio of the two monomer units in the template (microgels), the amount of Fe3O4 adsorbed and the amount of SiO2 deposited. The magnetic composite mi- crosphere surface was modified by the NH2 groups via silanization reagent (3-aminopropyltrimethoxysi- lane). It might be expected that this functional material can be applied for recognition of biomacromolecules and in biological medical fields.