Monolithic Silica Rods Grafted with Thermoresponsive Anionic Polymer Brushes for High-Speed Separation of Basic Biomolecules and Peptides

摘要

Thermoresponsive anionic copolymer brushes, poiy(N-isopropylacrylamide-co-acrylic acid-co-tert-butylacryla-mide) [P(IPAAm-co-AAc-co-tBAAm)], were grafted onto a monolithic silica rod column through surface-initiated atom-transfer radical polymerization (ATRP) to prepare an effective thermoresponsive anionic chromatography matrix. An ATRP initiator was attached to the rod: surface. N-Isopropylacrylamide (IPAAm), tert-butyl acrylate (tBA), tert-butylacrylamide (tBAAm), and the ATRP catayst CuCl/CuCl2/tris[2-(N,N-dimethylamino )ethyl] amine were dissolved in 2-propanol, and the reaction mixture was umped into the initiator-modified column. After grafting P(IPAAm-co-tBA-co-tBAAm) on the monolithic silica surfaces, deprotection of the tert-butyl group of tBA was performed. Chromatographic analysis showed that the prepared column was able to separate catecholamine derivatives and angiotensin subtypes within a shorter analysis time (S min) than a silica-bead-packed column modified With the same copolymer brush could. These results indicated that the prepared copolymer-modified monolithic silica rod column may be a promising bioanalytical and bioseparation tool for rapid analysis of basic bioactive compounds and peptides.