Highly sensitive real-time detection of DNA hybridization by using nanoporous waveguide fluorescence spectroscopy

摘要

In this Letter, we report highly sensitive fluorescence spectroscopy using a nanoporous waveguide (NPWG) comprising a porous anodic alumina (PAA) layer and an Al layer. Simulations show that the TE0 waveguide mode excited in the PAA layer produces an electromagnetic field whose intensity is 40-fold higher than that of the incident light, and which yields enhanced intensity when used to excite fluorophores. We demonstrate the sensing ability of the NPWG by incorporating it into a fluorescent sensor to monitor duplex DNA formation in real-time, with a detection limit as low as 20 pM.