This study reports for the first time the effect of different sodium halide salts (NaClO4, NaI, and Na2CO3) in the low concentration range (in the range of 10 −7 –1 M) on the swelling behavior of photo-crosslinked, surfaceimmobilized poly(N -isopropyl acrylamide) (PNIPAAm) terpolymer layers. PNIPAAm terpolymer (consisting of N - isopropylacrylamide, methacrylic acid, and 4-methacryloxybenzophenone) was synthesized via free radical polymerization. The PNIPAAm terpolymer layers were prepared on gold substrates via spin coating and crosslinked and surface attached via UV radiation. The swelling behavior of the layers in monovalent (NaClO4 and NaI) and divalent (Na2CO3) solutions was monitored by surface plasmon/optical waveguide spectroscopy. |
