Imak applications for the investigation of protein adsorption behaviors of bacterial originated extracellular biolopolimers

In this work, IMAC, a popular method of affinity chromatography, has been utilized effectively, for the purification of α-amylase, which is an important enzyme industrially. For the polymerization, poly (2-hydroxyethyl methacrylate) as monomer, glycidyl methacrylate (GMA) as co-monomer, N,N'-methylene-bis-acrylamide as crosslinker, extracellular polymeric materials (EPS) as metal binding, N,N,N ',N'-tetramethylenediamine (TEMED)/ammonium persulfate (APS) as activator/initiator and ethanol as porogen were used. PHEMA based composite membranes were synthesized in the petri dish by radical copolymerization method. Then, Cu2+ ions were attached to the membranes via EPSs. Prepared Cu2+ attached EPS-mixed membranes were characterized by scanning electron microscopy (SEM), swelling tests. The influence of parameters such as pH, α-amylase starting concentration, temperature, and ionic strength in α-amylase adsorption from aqueous medium is investigated. The highest adsorption capacity on Cu2+attached-EPS mixed polymer membranes (Cu2+-EPS-PM) was determined as 54,2 mg /g polymer at pH 5 sodium acetate buffer at 25°C in an initial α-amylase concentration of 2 mg/mL. Furthermore, it has been determined that the enzyme can be adsorbed and desorbed repeatedly on Cu2+-EPS-PM.