posted on 2023-12-27, 14:03authored byKodiadka Ayshathil Bushra, Yoon-Bo Shim, K. Sudhakara Prasad
Wearable sensors are effective point-of-care
(POC) diagnostic tools
for the timely analysis of a patient’s disease status. The
best way to achieve such biosensors is by developing a device for
the noninvasive investigation of human sweat. However, the ultralow
concentrations of biomarkers in sweat pose challenges to achieving
high sensitivity. The remarkable qualities of flexible paper field
effect transistors (PFETs), including their high modulation index,
pliability, transducing capability, and quick reaction, make them
potential candidates for wearable sensors. Our study presents a biodegradable,
disposable, scalable, low-cost PFET device for nonenzymatic, wearable
glucose sensing applications. In the sequence, we further discussed
the functionalization of the channel, electrodes, and sensing methods.
Here, the semiconducting silver (Ag) nanoparticle (NP)-decorated cuprous
oxide (Cu2O) dispersed on reduced graphene oxide (rGO)
was synthesized by a rapid, cheaper microwave-assisted method. Material
characterization techniques validate the nanocomposite (NC) formation,
which is patterned as the transistor channel. Charge (cation/anion)
generated due to the electrolytes (analyte) and NC interaction develops
interface potential and electric double layer (EDL)/capacitance change
that stimulates the channel conductivity. The faster electron and
hole mobility, coupled with the superior selectivity of Ag–Cu2O and the high conductivity of rGO, collectively contribute
to excellent electrocatalytic activity for glucose oxidation. The
fabricated PFET sensor could achieve a limit of detection (LOD) of
96 nM with high sensitivity and self-amplification effect. Real-time
applications using artificial sweat introduced with a physiological
range of sweat glucose concentrations (0.01–0.1 mM) yielded
promising findings, indicating the potential use of inexpensive and
sustainable PFETs for wearable glucose sensors.