In the next example, we demonstrate a spectrofluidic device, which aligns the channels with the direction of the ATR ridges, for conducting assay experiments. The microchannel feature contained 9 parallel channels (Figure ) each with a channel width of 0.4 mm and a 0.3 mm wall separating adjacent channels. Therefore, the centre-lines of each channel and ridge had the channel being matched to that of each ridge in the final spectrofluidic device (Figure ). The ASMAA was used to control the position of a 0.4 mm aperture such that it could jump to predefined positions corresponding to the mid-point of each channel/ridge assembly. As determined previously via simulation, an aperture width of 0.4 mm, translates to measurement zone width of 0.2 mm at the sample surface. It is understood that advantage of parallel ridge to aperture is the ability to admit more light into small channels. Thus, the measurement zone is expected to be centred within the channel, with no interference from either PDMS channel wall.