Dye-attached cryogels for reversible alcohol dehydrogenase immobilization

In this work, poly(HEMA-co-GMA) cryogel was synthesized by using cryopolymerization technique and this cryogel was functionalized with Cibacron Blue F3GA dye. Prepared dye attached cryogel was used for the reversible immobilization of alcohol dehydrogenase from its aqueous solution. Cibacron Blue F3GA attached poly(HEMA-co-GMA) cryogel was characterized by environmental scanning electron microscopy (ESEM), energy dispersive X-ray (EDX) analysis and swelling studies. Surface morphology of the cryogel was considerably porous and the pore size was found to be around 30-50 μm. Effects of medium pH, initial alcohol dehydrogenase concentration, medium temperature and ionic strength on the alcohol dehydrogenase adsorption were also investigated and maximum alcohol dehydrogenase adsorption onto the dye-attached cryogel was found to be 8.55 mg/g cryogel. Adsorbed alcohol dehydrogenase was desorbed from the cryogel by using 10 mL of NaCl solution (1.0 M; in pH 4.0 acetate buffer). Synthesized cryogel was able to reuse for 25 sequential cycles and it was found that, there was no negligible decrease in the adsorption capacity of the dye-attached cryogel.