Abstract
We report a new photothermal spectroscopy using diffraction grating nano channels for detection in nano space. Photothermal effect was detected as intensity change of a diffracted probe beam due to refractive index change of heated sample solution inside nanochannels. The concept was verified by nanochannels of ∼nm width × ∼nm depth. The LOD (Limit of Detection) for Sunset Yellow solutions was 1.0×10 Abs. Further development to get higher sensitivity utilizing "Alternate diffraction grating method" is now investigated. © 2006 Society for Chemistry and Micro-Nano Systems.