Preparation and characterization of surface modified gamma-Fe2O3 (maghemite)-silica nanocomposites used for the purification of benzaldehyde lyase

TURAL B., Sopaci S. B., ÖZKAN N., DEMİR A. G., Volkan M.

JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, vol.72, no.8, pp.968-973, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 72 Issue: 8
  • Publication Date: 2011
  • Doi Number: 10.1016/j.jpcs.2011.05.010
  • Journal Name: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.968-973
  • Keywords: Magnetic materials, Nanostructures, Surfaces, X-ray diffraction, Magnetic properties, IRON-OXIDE NANOPARTICLES, MAGNETIC NANOPARTICLES, PROTEIN ADSORPTION, NANOCRYSTALLINE GAMMA-FE2O3, BIOMEDICAL APPLICATIONS, TAGGED PROTEINS, MATRIX, SEPARATION, RECOVERY, SYSTEM
  • Middle East Technical University Affiliated: Yes

Abstract

gamma-Fe2O3 (maghemite)-silica nanocomposite particles were synthesized using a sol-gel method. The condensation products of 3-glycidoxy propyltrimethoxy silane (GPTMS) and nitrilotriacetic acid (NTA) were introduced onto the surfaces of the gamma-Fe2O3 silica nanocomposite particles and subsequently, these modified surfaces were complexed with cobalt (Co+2) metal ions. A possibility of using these surface modified gamma-Fe2O3-silica particles for the purification of 6 x histidine tagged recombinant benzaldehyde lyase (BAL, EC 4.1.2.38) based on magnetic separation was investigated. X-ray diffraction (XRD), thermal analysis, and vibrating sample magnetometry (VSM) methods were used to characterize the surface modified superparamagnetic gamma-Fe2O3 (maghemite)-silica nanoparticles. XRD (Scherer's equation) results indicate that the primary particle size of maghemite was around 11 nm. Magnetic characterization results confirmed that the gamma-Fe2O3 (maghemite)-silica nanoparticles were superparamagnetic. According to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results, these superparamagnetic nanoparticles specifically capture 6 x His-tagged BAL from crude extract of Escherichia coli (E. coli) BL21(DE3)pLysS/BAL(HIS). This study shows that the surface modified gamma-Fe2O3 (maghemite)-silica nanoparticles are eligible for immobilized metal-ion affinity adsorption for histidine tagged recombinant proteins with its high capacity (3.16 +/- 0.4 mg/g) and selectivity. (C) 2011 Elsevier Ltd. All rights reserved.