Nanobiophotonik

A novel scheme for the optical detection of a few or even single gold nanoparticle labels is introduced. It utilizes sub-wavelength holes in a chromium layer on a glass substrate, where a bioaffinity reaction could take place and the outcome (regarding particle label binding) can be monitored using optical means. Experiments in combination with simulations demonstrate that the presence of particles in such a chromium hole can be simply detected by using the color information of images recorded by a CCD camera without the need for additional spectroscopic setups. The presence of gold nanoparticles leads to a detectable red-shift in the images of the respective nanohole, which is the sensing principle of the sensor.