Enhanced biosensing performance of mesoporous SnO2 multilayer film in interfacing hemoglobin

J Nanosci Nanotechnol. 2009 Apr;9(4):2290-6. doi: 10.1166/jnn.2009.se23.

Abstract

Through alternative adsorption of dextran sulfate (DS) and mesoporous SnO2 (Meso-SnO2), {Meso-SnO2/DS}n films were constructed and applied for the immobilization of hemoglobin (Hb). For comparison, the same-sized non-mesoporous SnO2 nanopraticles (Nonmeso-SnO2) based films were also prepared. Thus-formed films were characterized by many techniques in detail. The electrochemical impedance spectroscopy (EIS, using ferricyanide/ferrocyanide as a redox probe) experiments confirmed the charge transfer resistance increased linearly with the number of Meso-SnO2/DS bilayers, which was smaller than that of Nonmeso-SnO2/DS bilayers. Further EIS, UV-vis and AFM experiments indicate that Meso-SnO2/DS film exhibit enhanced immobilization ability of Hb with favorable orientation in comparison with that of Nonmeso-SnO2/DS film. The adsorbed Hb at Meso-SnO2/DS film showed a good direct electron transfer behavior with the heterogeneous electron transfer rate constant (ks) of 8.89 +/-0.32 s(-1), and excellent electrocatalysis to the reduction of O2 and H2O2 in pH 7.0 buffers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Biosensing Techniques / methods*
  • Catalysis
  • Electrochemistry
  • Hemoglobins / chemistry*
  • Hemoglobins / metabolism*
  • Hemoglobins / ultrastructure
  • Humans
  • Immobilized Proteins / chemistry
  • Immobilized Proteins / metabolism
  • Immobilized Proteins / ultrastructure
  • Nanoparticles / chemistry*
  • Nanoparticles / ultrastructure
  • Tin Compounds / chemical synthesis*
  • Tin Compounds / chemistry

Substances

  • Hemoglobins
  • Immobilized Proteins
  • Tin Compounds
  • stannic oxide