Therapeutic affinity adsorption of iron(III) with dye- and ferritin-immobilized pHEMA adsorbent

Microporous poly(2-hydroxyethylmethacrylate) (pHEMA) films carrying cibacro n blue F3GA, Congo red, and ferritin were prepared and used for iron(III) r emoval from human plasma. pHEMA films were produced by a photopolymerizatio n of 2-hydroxyethylmethacrylate in the presence of azobisisobutyronitrile. The reactive dye ligands cibacron blue F3GA, Congo red, and bioligand ferri tin were then covalently attached to the pHEMA films. The maximum dye loadi ngs were 1.07 and 0.80 mu mol/cm(2) for cibacron blue and Congo red, respec tively. The maximum amount of ferritin attached was 1.04 x 10(-3) mu mol/cm (2). Characterizations of the films were achieved by contact-angle, water-u ptake, and scanning electron microscopy studies as well as atomic force mic roscopy images. The aqueous water-uptake properties and contact angles lair underwater of the pHEMA films did not change after derivatization with cib acron blue F3GA, Congo red, and ferritin. These hydrophilic films (contact angle = 45.3 degrees), having a swelling ratio of 58% (w/w) and carrying ci bacron blue F3GA, Congo red, and ferritin, were used in Fe(III) removal stu dies. The maximum amounts of Fe(III) removed from human plasma by cibacron blue F3GA-, Congo red-, and ferritin-attached pHEMA films were 3.80 mug/cm( 2) for cibacron blue F3GA, 4.41 mug/cm(2) for Congo red, and 8.1 mug/cm(2) for ferritin-attached films. Fe(III) ions could be repeatedly adsorbed and desorbed with these affinity pHEMA films without a noticeable loss in their Fe(III) adsorption capacity. (C) 2001 John Wiley & Sons, Inc.