Figure 5
Nanofluorescence experiments on the microfluidic device. (a) Represents a 3D scheme of the microfluidic sample holder. (b) Fluorescence spectrum collected at the central electrode. (c–d) Optical micrography of the channel and electrodes highlighting the ROI (magenta rectangle) scanned by a nanobeam of about 600 nm \(\times\) 600 nm. (e–f) Show the Au-\(L_{\alpha }\) (9713 eV) fluorescence maps about the circle 1 and 2 on the electrode border. (g–h) Au (\(L_{\alpha }\)), and Cr-\(K_{\alpha }\) (5.4 keV) maps obtained at the circle 3. The experiments were performed on the channels filled with water. The nano-XRF maps have a pixel size of 5 \(\mu\)m and an entire acquisition time of 65 s (22.5 ms per pixel or step).
