Poly(hydroxyethyl methacrylate-co-methacrylamidoalanine) membranes and their utilization as metal-chelate affinity adsorbents for lysozyme adsorption.
Different adsorbents have been reported in the literature for protein purification. The authors have developed a novel and new approach to obtain high protein adsorption capacity utilizing a 2-methacrylamidoalanine-containing membrane. Amino acid ligand 2-methacrylamidoalanine (MAAL) monomer was synthesized using methacryloyl chloride and alanine. Poly(2-hydroxyethylmethacrylate-co-2-methacrylamidoalanine) [p(HEMA-co-MAAL)] membranes were then prepared by UV-initiated photopolymerization of HEMA and MAAL in the presence of an initiator (azobisisobutyronitrile, AIBN). The synthesized MAAL monomer was characterized by NMR. p(HEMA-co-MAAL) membranes were characterized by swelling studies, porosimeter, SEM, FTIR, and elemental analysis. These membranes have macropores in the size range of 5-10 microm. Cu(II) ions (25.9 mmol/m2) were chelated on these membranes. p(HEMA-co-MAAL) membranes were used to study the adsorption of lysozyme from aqueous media containing different amounts of lysozyme (0.1-3.0 mg/l) and at different pH values (4.0-8.0). The non-specific adsorption of lysozyme on the pHEMA membranes was negligible (0.9 microg/cm2). Incorporation of MAAL increased the lysozyme adsorption significantly up to 2.96 mg/cm2. The lysozyme adsorption capacity of the Cu(II) incorporated membranes (9.98 mg/cm2) was greater than that of the p(HEMA-co-MAAL) membranes. More than 90% of the adsorbed lysozyme was desorbed in 1 h in the desorption medium containing 1.0 M NaCl and 0.025 M EDTA. The metal-chelate affinity membranes are suitable for repeated use for more than ten cycles without a noticeable loss of capacity.
Garipcan
Bora
B
Department of Chemistry, Hacettepe University, Ankara, Turkey.
Say
Ridvan
R
Patir
Süleyman
S
Arica
Yakup
Y
Denizli
Adil
A
D000327:Adsorption; D002614:Chelating Agents / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D008854:Microscopy, Electron; D009113:Muramidase / Q000378:metabolism*; D011102:Polyhydroxyethyl Methacrylate / Q000138:chemical synthesis / Q000737:chemistry*; D013696:Temperature
D002614:Chelating Agents; D008567:Membranes, Artificial; D011102:Polyhydroxyethyl Methacrylate; D003300:Copper; D009113:Muramidase