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Design and fabrication of low-loss nonlinear polymer waveguides with attenuation smaller than 2 dB/cm are reported. Electro-optic devices based on this polymer such as phase modulators and Mach-Zehnder interferometers, have been fabricated and demonstrated. The best figures obtained so far at 1.32 /spl mu/m are V/sub /spl pi//=10 V for the phase modulator inserted between crossed polarizers and V/sub /spl pi//=9 V for the Mach-Zehnder modulator working in TM polarization. The electro-optic polymer is stable at 85/spl deg/C for more than 2000 hours.

Electro-optic polymers provide an interesting alternative to bulk materials such as Lithium Niobate for a range of applications encompassing electro-optic modulators, switches, or directional couplers. The ability of polymers to be spin-coated on semiconductor substrates and their compatibility with such processing techniques as photolithography or reactive ion etching, now classically used in III-V semiconductor-based optoelectronics, provide a relevant technological background towards their integration in optronic circuits.

A simple method for covalent coupling of proteins to filter paper modified with quinone groups is described. This paper, termed ‘Key paper’ is flexible, stable on storage and does not require any activation before use. Proteins bound to Key paper can be detected by enzyme immunoassay, radioimmunoassay or Coomassie blue staining. Bound enzymes retain their enzymatic activity. Nucleic acids do not bind and do not interfere with the activity of the bound proteins. Because of its mechanical and chemical properties Key paper is a good matrix for electroblotting and for direct in situ analysis of proteins.