[23a-C105-1~11] 12.3 Functional Materials and Novel Devices

▼ [23a-C105-11] Small biomolecule detection based on small-signal transconductance of suspended double-network hydrogels as organic electrochemical transistors

〇(P)Alex ChiWei Tseng¹, Toshiya Sakata¹ (1.Univ. of Tokyo)

Keywords:conductive polymer, double-network hydrogel, phenylboronic acid

Semiconducting double-network hydrogels based on PEDOT:PSS and functionalized polyacrylamide bearing phenylboronic acid (PBA) groups may be employed as channels of organic electrochemical transistors for the detection of small biomolecules with cis-diol groups such as glucose or catecholamines. The sensing response is based on coupling of the PBA-diol binding equilibrium and rate of O₂ reduction electrocatalyzed by reduced PEDOT in cathodic potentials, neatly avoiding oxidizing conditions with common biological interferents. Accordingly, this mechanism affords both thermodynamic and kinetic control of sensing via selection of DC and AC parameters in small-signal transconductance measurements. Moreover, mass transport is improved by exploiting the mechanical strength of hydrogel structure by employing a suspended channel structure that gives 3D access to ions and analyte. Sub-millimolar sensitivity towards glucose is demonstrated and is promising for non-invasive monitoring application.