POLY(N-ISOPROPYLACRYLAMIDE) CARRYING DOUBLE-STRANDED DNA FOR AFFINITYSEPARATION OF GENOTOXINS

We immobilized double-stranded DNA on poly(N-isopropylacrylamide), whi ch is temperature-sensitive and gives precipitates from an aqueous sol ution when heated over 31 degrees C. Photochemical conjugation with a vinyl derivative of psoralen was demonstrated to make the DNA polymeri zable with a vinyl monomer. The radical copolymerization with N-isopro pylacrylamide gave the temperature-responsive conjugate. The conjugate was shown to capture ethidium, a DNA-binding genotoxin, and precipita te with it when heated. About 95% of ethidium was separated from its h ighly diluted solution (3 ppm).