POLY(ETHYLENE OXIDE) HYDROGELS CONTAINING IMMOBILIZED PARTICLES OF ANLC DISPERSION OF DEOXYRIBONUCLEIC-ACID

Hydrogels containing immobilized particles of a cholesteric LC dispers ion of desoxyribonucleic acid with a particle size of about 10(3) Angs trom in diameter were prepared by phase segregation of DNA from aqueou s saline solutions induced by PEG-based methacrylate macromonomers and subsequent radical polymerization. The immobilization of DNA particle s did not destroy the abnormal optical activity manifested as an inten se band at 275-280 nm in the circular dichroism spectrum. The amplitud e of this band significantly varied during the gel formation and also during the swelling or osmotic deswelling which are associated with th e variation of polymer concentration in the gels. We suggest a semiqua ntitative interpretation of the behavior of LC particles in the gels w hich rests on the theory of phase segregation of DNA by PEG. Applicati ons of gel-entrapped LC particles of DNA as microscopic probes sensiti ve to the swelling pressure of polymer network or as a principal eleme nt of biosensors of essentially new type are discussed.