International Eurasian Conference onBiological and Chemical Sciences(EurasianBioChem 2018), Ankara, Turkey, 26 - 27 April 2018, pp.1334
Abstract Cryogels
are super-macroporous hydrogels characterized with a heterogeneous
open-porous structure, and which are prepared at sub-zero temperatures. These
hydrogels offer new viewpoints for construction of innovative systems for
biotechnological, biomedical and pharmaceutical applications. They can be
used as an alternative adsorbents instead of the beaded form materials due to
their large pores, short diffusion paths, low pressure drop and very short
times adsorption and elution of the target macromolecules. There are many
reports about the utilization of the cryogels as support materials for
immobilization of biological macromolecules (such as enzymes, nucleic acids)
that give better results than those of the traditional gel carriers. The affinity cryogel adsorbents can
be prepared by modification of the surface of the hydrogels. The ligands
molecules can be selected according to the physical characteristic of the
target protein in biological fluid and immobilized via covalent bond on the
surface of the cryogel, then, used for purification of the target protein. The poly(2-hydroxyethyl
methacrylate-glycidyl methacrylate), p(HEMA-GMA), cryogels were synthesized
via freeze drying (lyophilization) technique using ethylene glycol
dimethacrylate as cross-linker. Chemical
modification the cryogels was realized by treatment with tris(2-aminoethyl)amine
or sodium sulfide. The functional amine and sulfonic acid groups were created
on the cryogel surface with this modification process. Cryogels were
characterized by ATR-FTIR, swelling tests and surface area measurement.
Adsorptive properties of the p(HEMA-GMA)-NH2 and p(HEMA-GMA)-SO3H
cryogels were investigated for lysozyme by varying pH, contact time, ionic
strength, initial lysozyme concentration, and temperature. The optimum lysozyme
adsorption was observed at pH 7.0 for both p(HEMA-GMA)-NH2 and
p(HEMA-GMA)-SO3H cryogels. Desorption of the adsorbed lysozyme
from the cryogels was studied in a batch system. The amount of the adsorbed
lysozyme was desorbed about to 68% and 76% for p(HEMA-GMA)-NH2 and
p(HEMA-GMA)-SO3H cryogels, respectively, in all cases when KSCN
was used as eluent agent.
Keywords: Cryogel; Adsorption; Lysozyme |