Magnetic hydrogel microspheres 1.5 mum in size were prepared by dispersion
copolymerization of 2-hydroxyethyl methacrylate and ethylene dimethacrylate
in the presence of magnetite, which formed the core of the particles. RNas
e A was coupled to the particles by the cyanuric chloride method. Gel elect
rophoresis of plasmid DNA pUC 19 (contaminated by bacterial RNA) confirmed
RNA degradation with the immobilized enzyme. The effect of temperature and
pH on the relative activity of immobilized RNase A was estimated after incu
bation of the samples at different temperatures (30-80 degreesC) and pH (4.
0-8.0). Maximum relative activity was observed at 70 degreesC and pH 6.5. T
he matrices based on magnetic poly(HEMA) had a low tendency to adsorb RNA.