Optical Readout of a Nanoparticle Based Sensor by Cavity Ring-Down Spectroscopy

in: Sensors and Actuators B-Chemical (2014)
Zeuner, Thomas; Paa, Wolfgang; Schmidl, Gabriele; Zopf, David; Henkel, Thomas; Csáki, Andrea; Fritzsche, Wolfgang
We combine the plasmonic properties of metallic nanoparticles enabling a label-free bioanalytical approach with the cavity ring-down method (CRD) in a miniaturized fluidic device as a sensitive and fast optical photon lifetime measurement. Nanoparticles (Ag triangles and Au nanodots) are immobilized within a specially designed microfluidic chip (MFC) that is situated inside an optical cavity. Our approach allows to measure absorption / loss changes of 0.02% – well below the typical detection limit (< 1%) of conventional spectrometers. The proof of principle is demonstrated by sensing refractive index changes of the solution inside the chip. Furthermore, a first bioanalytical application example is presented. Therefore, the binding of 2x10^8 DNA sequences from the phytopathogene microorganism Phytophthora kernoviae onto nanoparticles functionalized with complementary DNA molecules could be detected.

Third party cookies & scripts

This site uses cookies. For optimal performance, smooth social media and promotional use, it is recommended that you agree to third party cookies and scripts. This may involve sharing information about your use of the third-party social media, advertising and analytics website.
For more information, see privacy policy and imprint.
Which cookies & scripts and the associated processing of your personal data do you agree with?

You can change your preferences anytime by visiting privacy policy.