Byun Jang-Woong, Kim Jong-Uk, Chung Woo-Jae, Lee Yoon-Sik
School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea.
Macromol Biosci. 2004 May 17;4(5):512-9. doi: 10.1002/mabi.200300071.
We prepared surface-grafted polystyrene (PS) beads with comb-like poly(ethylene glycol) (PEG) chains. To accomplish this, conventional gel-type PS beads (35-75 microm) were treated with ozone gas to introduce hydroperoxide groups onto the surface. Using these hydroperoxide groups, poly(methyl methacrylate) (PMMA, Mn= 22,000-25,000) was grafted onto the surface of the PS beads. The ester groups of the grafted PMMA were reduced to hydroxyl groups with lithium aluminum hydride (LAH). After adding ethylene oxide (EO) to the hydroxyl groups, we obtained the PS-sg-PEG beads, which had a rugged surface and a diameter of 80-150 microm. We could obtain several kinds of the PS-sg-PEG beads by controlling the chain lengths of the grafted PMMA and the molecular weights of the PEG chains. The grafted PEG layer was about 30-50 microm thick, which was verified from the cross-sectioned views of the fluorescamine-labeled beads. These fluorescence images proved that the beads possessed a pellicular structure. Furthermore, we found that the surface-grafted PEG chains had the characteristic property of reducing non-specific protein adsorption on the beads.
我们制备了带有梳状聚乙二醇（PEG）链的表面接枝聚苯乙烯（PS）珠。为此，将常规凝胶型PS珠（35 - 75微米）用臭氧气体处理，以在表面引入过氧化氢基团。利用这些过氧化氢基团，将聚甲基丙烯酸甲酯（PMMA，Mn = 22,000 - 25,000）接枝到PS珠的表面。用氢化铝锂（LAH）将接枝的PMMA的酯基还原为羟基。在向羟基中加入环氧乙烷（EO）后，我们得到了表面粗糙、直径为80 - 150微米的PS-sg-PEG珠。通过控制接枝PMMA的链长和PEG链的分子量，我们可以得到几种PS-sg-PEG珠。接枝的PEG层厚度约为30 - 50微米，这从荧光胺标记珠的横截面视图得到了证实。这些荧光图像证明这些珠具有薄膜结构。此外，我们发现表面接枝的PEG链具有减少珠子上非特异性蛋白质吸附的特性。
