Microfluidic isotachophoresis (ITP) is an electrophoretic technique that can be used to concentrate analytes, thereby facilitating and accelerating their detection. The fluorescence images show the isotachophoretic transport of Alexa fluor 647 carboxylic acid (AF 647) with a constant current of 5 µA. Constant-current ITP has the main effect that the velocity at which the sample migrates through the microchannel is constant over time.

By choosing sample concentrations between 0 and 10 ng/L, the signal-to-noise ratio is varied. Only at higher concentrations can the sample be detected without further image processing. The data were obtained to test the capability of a newly developed image processing method that allows the detection of samples even at low concentrations without any additional instrumentation effort.

The fluorescence images were obtained with a Nikon Eclipse Ti microscope and an Andor iXon+ 897 EMCCD camera. A 10x S-Fluor objective (NA = 0.5, Nikon) and a 639 nm laser were used. The exposure time was set to 20 ms and the frame rate to 46 fps. More information on the experimental procedure can be found in the paper that will be linked below.