A PEDOT:PSS conductive hydrogel incorporated with Prussian blue nanoparticles for wearable and noninvasive monitoring of glucose

Currently, there is no commercially-available noninvasive method for glucose monitoring in the interstitial fluid (ISF) mainly due to the measurement accuracy, sensitivity and/or the weak blood correlation. Here, we present an electrochemical biosensor based on PEDOT:PSS conductive hydrogel incorporated with Prussian blue nanoparticles (PBNPs) for the noninvasive and continuous monitoring of glucose on body. The hydrogel was prepared with the addition of dimethyl sulfoxide (DMSO) and Zonyl FS-300, which helped to improve the expanding of the polymer chains for the formation of better conductive and nanoporous networks. The hydrogel-based biosensor showed a low detection limit of 0.85 μM for glucose detection and high sensitivity up to 340.1 μA·mM−1·cm−2, which was about 10-fold higher than the counterparts based on agarose and hydroxyethyl methacrylate (HEMA) hydrogels. Furthermore, it provided good accuracy with commercial glucometer for the glucose detection in serum. More importantly, incorporated with the reverse iontophoresis (RI), the hydrogel was applied as a skin patch on human subject for the in vivo noninvasive and continuous monitoring of ISF-borne glucose. The results showed good correlation with that measured by blood glucometer. We believe such glucose biosensor paves the way to clinically wearable noninvasive glucose monitoring in diabetics.