Novel magnetic microspheres on the basis of poly(vinyl alcohol) as affinity medium for quantitative detection of...

A water-in-oil suspension cross-linking technique using poly(vinyl alcohol) as polymer phase to prepare novel magnetic microbeads is described. By dispersing a conventional Fe3O4 pigment in the polymer phase and subsequently suspending the mixture in a vegetable oil phase with a defined viscosity, spherical magnetic microspheres are obtained. Bead sizes ranging from 1 to 50 microns and above can be obtained by exploiting well defined preparation parameters such as polymer concentration and oil and polymer viscosity. The performance of the magnetic matrices for the separation and quantification of glycated haemoglobin was tested using a m-aminophenylboronic acid matrix. The feasibility of this detection method for blood sugar diagnosis is discussed using a commercial column test kit for comparison.