Immobilized Chitosan Beads as Adsorbents for Selective Removal of Immunoproteins

*Author to whom correspondence should be addressed. ABSTRACT: The use of adsorbents for the treatment of patients suffering from various immune diseases is still in its infancy. Therefore, the development of selective adsorbents for the removal or decrease of immunoproteins from plasma is of great importance. In this study, chitosan, a natural polysaccharide having structural character-istics similar to glycosamino glycans, which is non-toxic and biocompatible, has been used for protein adsorption studies. Amino acids like phenyl alanine and tryptophan in different ratios are bonded to these polymers to observe immuno-adsorption. Several layers of phenyl alanine or tryptophan have been coated covalently on chitosan beads using N2-plasma, carbodiimide or glutaraldehyde treatments. Scanning electron micrographs have revealed the surface morpho-logical changes after such modifications. The surface modified chitosan beads have exhibited high binding affinity for γ-globulin compared to bare beads. It is also observed that the amount of fibrinogen adsorption is reduced on modified substrate. A selective removal of IgG and IgM has also been observed with these modified matrix when tested with human plasma, using immuno diffusion methods. The modified chitosan membranes have demonstrated a reduction in platelet attachment, showing that these substrates have become more blood compati-ble. Hence, it appears that modified chitosan surfaces may be an excellent sor-bent system for haemoperfusion due to their high binding affinity for immuno-at PENNSYLVANIA STATE UNIV on September 11, 2016jba.sagepub.comDownloaded from 386 proteins and blood compatibility. Further studies are needed to determine the behaviour under clinical conditions