𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Surface-Grafted Polystyrene Beads with Comb-Like Poly(ethylene glycol) Chains: Preparation and Biological Application

✍ Scribed by Jang-Woong Byun; Jong-Uk Kim; Woo-Jae Chung; Yoon-Sik Lee


Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
190 KB
Volume
4
Category
Article
ISSN
1616-5187

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

Summary: 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 μm) were treated with ozone gas to introduce hydroperoxide groups onto the surface. Using these hydroperoxide groups, poly(methyl methacrylate) (PMMA, $\overline M _{\rm n}$ = 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 μm. 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 μm 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.

Cross‐sectioned photograph of fluorescence‐labeled PS‐sg‐PEG beads showing their pellicular structure.

imageCross‐sectioned photograph of fluorescence‐labeled PS‐sg‐PEG beads showing their pellicular structure.