The effect of the chelator characteristics on insulin adsorption in immobilized metal affinity chromatography

Abstract

Abstract The fact that cryogels have been highly preferred (especially as adsorbent) by scientists in chromatographic processes has made these polymers very popular. In this study, Poly(2-Hydroxyethyl methacrylate-Glycidyl methacrylate), Poly(HEMA-GMA), cryogels were synthesized and then p-aminobenzoic acid, and p-aminopyridine compounds were ligated as a ligand to the structure. In the final stage, a metal ion [Cu(II), Ag(I) or Zn(II)] was immobilized to the polymeric structure, and these structures were used in the adsorption of the insulin molecule from aqueous systems. The highest insulin adsorption performance was observed in cryogel which the p-aminopyridine ligand was bound, and the Cu(II) ions were immobilized. This cryogel was coded as Pr-Cu(II). The insulin adsorption capacity of the Pr-Cu(II) cryogel was tested under varying pH, interaction time, initial insulin concentration, temperature, and ionic strength. On behalf of the characterization works; Fourier Transform Infrared Spectroscopy (FT-IR) analysis, Scanning Electron Microscopy (SEM) analysis, thermal analysis, surface area analysis, elemental analysis, Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), and Computerized Microtomography (μCT) analysis were performed. The adsorption capacity of the cryogels was calculated to be approximately 242 mg insulin/g cryogel. Additionally, Langmuir isotherm and pseudo-second-order models were found to be suitable for isotherm-kinetic studies of adsorption interaction.