Planar integrated optical waveguide used as a transducer to yield chemical information: Detection of the activity of proteolytic enzymes e.g. serine-proteases

Gleb Zhylyak, Victor Ramoz-Perez, Michael Linnhoff, Thomas Hug, Daniel Citterio, Ursula E. Spichiger-Keller

Research output: Contribution to journalArticle

9 Citations (Scopus)


The paper shows the very first results of a feasibility study where the activity of proteolytic enzymes towards dye-labelled artificial substrates immobilized on the surface of planar optical Ta2O5 waveguide was investigated. Within this project, a chromophore label was developed, synthesized and attached to the carboxy-terminus of specific tripeptides. The goal was to develop a highly sensitive optical assay in order to monitor the activity of serine-proteases by cleavage of the amide bond between peptide and chromophore. On the one hand, a strategy was developed to immobilize the labeled tripeptide unto integrated planar waveguides. On the other hand, an instrument, the so-called "chip-reader" was developed to detect the biological process on the surface of the integrated planar optical waveguide. Surface characteristics were analyzed by XPS, TOF-SIMS and contact angle measurements. A comparison between the effectivity of ATR-photometry on chip using TE0 mode and photometry in transmission mode is discussed.

Original languageEnglish
Pages (from-to)603-617
Number of pages15
JournalOptics and Lasers in Engineering
Issue number3-5
Publication statusPublished - 2005 Mar 1



  • ATR-measurements in the rarer medium
  • Absorbance measurements
  • Absorption wavelength >630 nm
  • Cancer diagnostics
  • Detection in human blood
  • Evanescent field
  • Multiplexing
  • Screening of tumorstatic activity
  • Tracing of endotoxin

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Mechanical Engineering
  • Electrical and Electronic Engineering

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