Fig. 2.

a) Scheme of the CCD camera, and b) protocol for the ultra-high sensitivity CL detection of salivary IgA by the developed immunosensor. After completion of the IgA-LFIA (1), a transparent glass fibre pad (which was pre-impregnated with the CL cocktail substrate) is placed onto the membrane at the test and control line (2). 20 μl of water is added to assist the re-suspension of the CL substrate; finally, the strip is placed in the holder of the cooled CCD camera for lens-free imaging detection (3).