Screen-printed biosensor chips with Prussian blue nanocubes for the detection of physiological analytes

A Prussian blue (PB) biosensor chip with the nanocubic crystals was fabricated in batch by a screen printing technique for the general detection of various physiological substances. Through a low-speed chemical synthesis approach, the nanostructure of PB slurry was well controlled to be a 100 nm nanocube by the synthesis temperature and reactant concentration. Then, PB slurry was screen-printed as the working electrode to construct a microchip by the integration of the printed reference and counter electrodes. Due to the high electrocatalytic activity attributed by the regular nanostructure of PB electrode, the as-prepared chips exhibited the generally high sensitivities of 83.404, 31.642 and 6.379 μA mM−1 cm−2 for the respective detections of glucose, glutamate and lactate, as well as the excellent selectivity, reproducibility and stability under the low work potential of −0.05 V.