Biosilica-based immobilization strategy for label-free OWLS sensors

Nóra Adányi, Zsuzsanna Bori, István Szendrö, Katalin Erdélyi, Xiaohong Wang, Heinz C. Schröder, Werner E.G. Müller

Research output: Contribution to journalArticle

4 Citations (Scopus)


In the last years, a new group of enzymes, so-called silicateins, have been identified and characterized, which form the axial filaments of the spicules of the siliceous sponges, consisting of amorphous silica. Silicateins are able to catalyze the polycondensation and deposition of silica at mild conditions (low temperature and physiological pH). By means of these enzymes it is possible for the first time to produce silica nanostructures biocatalytically, which opens new ways for construction of biosensors. The cDNAs encoding the responsible enzymes have been isolated and the proteins can be produced in a recombinant way. Here we demonstrate the silicatein-mediated biosilica formation on the surface of SiO2 sensors in model measurements using Optical Waveguide Lightmode Spectroscopy (OWLS) for real-time evaluation. The efficiency of the enzyme reaction on the surface of the SiO2 chips was studied and the parameters of this process were optimized. Silicatein can be expressed in Escherichia coli and the resulting recombinant protein is able to catalyze the formation of silica shell around the bacterial cells. The described immobilization strategy provides a novel technology for the development of microbial biosensors.

Original languageEnglish
Pages (from-to)1-7
Number of pages7
JournalSensors and Actuators, B: Chemical
Publication statusPublished - Jan 7 2013



  • Biosilica
  • E. coli
  • Optical Waveguide Lightmode Spectroscopy
  • Silicatein

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Instrumentation
  • Condensed Matter Physics
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Electrical and Electronic Engineering
  • Materials Chemistry

Cite this

Adányi, N., Bori, Z., Szendrö, I., Erdélyi, K., Wang, X., Schröder, H. C., & Müller, W. E. G. (2013). Biosilica-based immobilization strategy for label-free OWLS sensors. Sensors and Actuators, B: Chemical, 177, 1-7.