Gel permeation chromatography using porous glass beads modified with temperature-responsive polymers

Poly(N-isopropylacrylamide) (PIPA) with a carboxyl group at its end was coupled with amino group-carrying porous glass beads by the active-ester method. Gel permeation chromatography of dextran was carried out by using a column packed with the PIPA-carrying glass beads. The chromatograms of dextrans with various molecular weights are strongly affected by temperature: the elution time of dextran is largely changed between 25 and 32°C due to a change in the effective pore size by the transition of the PIPA chains from coils to globules on the surface of the pores of the glass beads. These results suggest the usability of PIPA-carrying glass beads as devices for thermo-controllable chromatography.