Fig. 5. Demonstration of the mechanism, fabrication and sensing performances of the inkjet-printed PAni-based biosensor. (a) Schematic illustration of the reaction mechanism of a PAni-based biosensor. (b) Schematic illustration of the fabrication of the inkjet-printed multiplexed PAni-based biosensor. Precursor solutions A and B; chloroplatinic acid (P) and formic acid (F) solutions; and enzyme solutions G (glucose oxidase solution), L (lactic oxidase solution), and T (mixed solution of lipase/glycerol kinase/l-α-glycerophosphate oxidase) are inkjet printed onto predefined areas of the working electrode. Three layers are then assembled to enable the multiplexed detection of metabolites. The inset shows a photo of the multiplexed sensors. (c) Instant response curves and repeatability of biosensors when detecting metabolite solutions of different concentrations. (d) The real-time signals collected from different electrodes when mixed metabolite solutions are pumped into the essay. Reprinted with permission from ref. 6 (copyright 2018 American Chemical Society).
