Abstract

The aim of this study was to develop gelatin coated polystyrene (PS) microcarriers with good cell adhesion and proliferation properties. PS microspheres, prepared using oil-in water (o/w) solvent evaporation method, were loaded with oxygen containing functional groups using an ultraviolet/ozone (UVO₃) system. Using water-soluble carbodiimide chemistry, gelatin was subsequently immobilized on UVO₃ treated PS microspheres. The amount of immobilized gelatin was found to be directly proportional to the surface carboxyl (COOH) concentration on PS microspheres. Face Centered Central Composite Design (FCCD) was employed to optimize the process conditions of UVO₃ treatment to maximize the surface COOH concentration on PS microspheres for allowing higher gelatin immobilization. Statistical results revealed that, the optimized process conditions were ozone flow rate of ∼64,603 ppm, exposure time of ∼60 minutes and sample amount of 5.05 g. Under these conditions, the surface COOH concentration on PS microspheres was ∼1,505 nmol/g with the corresponding amount of immobilized gelatin was ∼2,725 µg/g. Characterization analyses strongly suggest that the optimized UVO₃ treatment and successive gelatin immobilization have successfully improved surface wettability and dispersion stability of PS microspheres. Moreover, gelatin coated PS microcarriers were also proven as able to support the growth of CHO-K1 cells in high cell density culture.

摘要

本研究的目的是开发具有良好细胞粘附和增殖特性的明胶包被的聚苯乙烯 (PS) 微载体。_{使用水包油 (o/w) 溶剂蒸发法制备的 PS 微球，使用紫外线/臭氧 (UVO 3} ) 系统装载含氧官能团。使用水溶性碳二亚胺化学，随后将明胶固定在经过 UVO ₃处理的 PS 微球上。发现固定明胶的量与 PS 微球上的表面羧基 (COOH) 浓度成正比。采用面心中心复合设计 (FCCD) 优化 UVO _{3的工艺条件}处理以最大化 PS 微球上的表面 COOH 浓度，以实现更高的明胶固定。统计结果表明，优化的工艺条件为臭氧流速为~64,603 ppm，暴露时间为~60 分钟，样品量为5.05 g。在这些条件下，PS 微球上的表面 COOH 浓度约为 1,505 nmol/g，相应的固定明胶量约为 2,725 µg/g。表征分析强烈表明，优化的 UVO ₃处理和连续的明胶固定已成功地提高了 PS 微球的表面润湿性和分散稳定性。此外，明胶包被的 PS 微载体也被证明能够支持 CHO-K1 细胞在高细胞密度培养中的生长。