ИСТИНА

The thin (nanosized) microgel and microgel/enzyme films were fabricated on conductive substrates (graphite, gold) via two-steps, sequential adsorption of dual (pH and temperature) stimuli-responsive functional microgels, viz,, poly(N-isopropylacrylamide-co-N-[3-(dimethylamino)propyl]methacrylamide), P(NIPAM-co-DMAPMA), or poly(N-isopropylacrylamide-co-N-(3-aminopropyl)methacrylamide), P(NIPAM-co-APMA) followed by adsorption of enzymes (choline oxidase, tyrosinase, butyrylcholine esterase) under different pH and temperature conditions. Both stimuli (pH and temperature) can synergistically control the surface coverage by microgel particles and therefore determine efficiency of the following enzyme uptake. Further, we highlight that the loading of the microgel films by the enzymes strongly depends on the microgel architecture, on the state of the adsorbed microgel particles (swollen vs. collapsed) and on the molecular weight (globule size) of the enzyme. With help of the P(NIPAM-co-DMAPMA) microgel, the bienzymatic biosensor system with spatially separated enzymes was prepared in one-step, while the stabilized biosensor system with high operational stability was designed using the P(NIPAM-co-APMA) microgel via covalent cross-linking of enzyme globules to its primary aminogroups. (O-55, p. 139)