A background spectrum was acquired from each channel/ridge mid-position, when the channels were filled with dye water. As a proof-of-concept, the evaluation of each separate channel content was verified using 0.1 M Na2HPO4 solution admitted to channels 1, 3, 5, 7, and 9 while pure water was admitted to channels 2, 4, 6, and 8. Each inlet was connected via a separate syringe pumping at a flow rate of Q = 0.5 mL•h -1 . Spectra were obtained from each channel by stepping the aperture by 0.7 mm increments. Result showed the expected spectral signatures from the Na2HPO4 solution while the channels that contained water showed no bands due to the background scan matching that of the sample (Figure ). Moreover, the water-containing flow streams showed no spectral contamination from the Na2HPO4 solution. The absorbance area for the Na2HPO4 characteristic band (1072 cm -1 ) was analysed for each channel (Figure ).