The aim of the present study is to develop new magnetic polymer microspheres with
functional groups available for easy protein and antibody binding. Monodisperse
macroporous poly(2-hydroxyethyl methacrylate) (PHEMA-COOH) microspheres
~4 µm in diameter and containing ∼1 mmol COOH/g
were synthesized by multistep swelling polymerization of 2-hydroxyethyl methacrylate
(HEMA), ethylene dimethacrylate (EDMA), and 2-[(methoxycarbonyl)methoxy]ethyl
methacrylate (MCMEMA), which was followed by MCMEMA hydrolysis. The microspheres were
rendered magnetic by precipitation of iron oxide inside the pores, which made them
easily separable in a magnetic field. Properties of the resulting magnetic
poly(2-hydroxyethyl methacrylate) (mgt.PHEMA) particles with COOH functionality were
examined by scanning and transmission electron microscopy (SEM and TEM), static
volumetric adsorption of helium and nitrogen, mercury porosimetry, Fourier transform
infrared (FTIR) and atomic absorption spectroscopy (AAS), and elemental analysis.
Mgt.PHEMA microspheres were coupled with p46/Myo1C protein purified from blood
serum of multiple sclerosis (MS) patients, which enabled easy isolation of
monospecific anti-p46/Myo1C immunoglobulin G (IgG) antibodies from crude
antibody preparations of mouse blood serum. High efficiency of this approach was
confirmed by SDS/PAGE, Western blot, and dot blot analyses. The newly
developed mgt.PHEMA microspheres conjugated with a potential disease biomarker,
p46/Myo1C protein, are thus a promising tool for affinity purification of
antibodies, which can improve diagnosis and treatment of MS patients.