IMAC applications for DNA purification of bacterial originated extracellular biopolymeric composite cryogels

In this study, Immobilized Metal Affinity Chromatograph (IMAC) finding a wide field of application among affinity chromatography techniques in the last years was operated efficiently for separation of DNA from aqueous solutions. In the study, Fe+3 binded EPS- poly(2-hydroxyethyl methacrylate) composite cryogels was synthesized. For this aim, as monomer 2-hydroxyethyl methacrylate (HEMA), as cross-linker N,N´-methylene-bis-acrylamide (MBAAm), as initiator/activator pairs ammonium persulfate (APS) and N,N,N´,N´- tetramethyl ethylene diamine (TEMED) were used. After adding of extracellular polymeric substances (EPS) to polymerizaton media, obtained mixture was poured into a plastic syringe of 2,5 mL and left for polymerization in -12°C. After binding of Fe+3 ions, Fe+3 binded EPS PHEMA composite cryogels were analyzed by, SEM, swelling tests measurements. The effect of pH, initial DNA concentration, ionic strength, flow rate and temperature on adsorption were conducted. The highest amount of DNA adsorption from aqueous solution was 39,7 mg/g particles in acetate buffer at pH 6 with initial DNA concentration of 2 mg/mL with the 0,5 mL/min flow rate, at 25 ºC temperature. It was also made observation that DNA could be over and over adsorbed and desorbed on the Fe+3 binded EPS-PHEMA composite cryogels.