Dual Functional Conjugated Acetylenic Polymers: High-Efficacy Modulation for Organic Photoelectrochemical Transistors and Structural Evolution for Bioelectronic Detection

Abstract

Conjugated acetylenic polymers (CAPs) have emerged as a unique class of metal-free semiconductors with tunable electrical and optical properties yet their full potential remains largely unexplored. Organic bioelectronics is envisioned to create more opportunities for innovative biomedical applications. Herein, we report a poly(1,4-diethynylbenzene) (pDEB)/NiO gated enhancement-mode poly(ethylene dioxythiophene)–poly(styrene sulfonate) organic photoelectrochemical transistor (OPECT) and its structural evolution toward bioelectronic detection. pDEB was synthesized via copper-mediated Glaser polycondensation of DEB monomers on the NiO/FTO substrate, and the as-synthesized pDEB/NiO/FTO can efficiently modulate the enhancement-mode device with a high current gain. Linking with a sandwich immunoassay, the labeled alkaline phosphatase can catalyze sodium thiophosphate to generate H2S, which will react with the diacetylene group in pDEB through the Michael addition reaction, resulting in an altered molecular structure and thus the transistor response. Exemplified by HIgG as the model target, the developed biosensor achieves highly sensitive detection with a linear range of 70 fg mL–1–10 ng mL–1 and a low detection limit of 28.5 fg mL–1. This work features the dual functional CAP-gated OPECT, providing not only a novel gating module but also a structurally new rationale for bioelectronic detection.

Biological Transformation of AgI on MOF-on-MOF-Derived Heterostructures: Toward Polarity-Switchable Photoelectrochemical Biosensors for Neuron-Specific Enolase

“…The analytical performance of the ZnO@In 2 O 3 @AgI-5 PEC sensing platform toward the targeted NSE was evaluated. As illustrated in the inset in Figure a, when NSE was present, the ALP restricted by ZIF-8 labeled on mAb 2 could catalyze the Na 3 SPO 3 substrate to produce H 2 S. , The generated H 2 S concentration is proportional to the concentration of NSE, resulting in a reversal from a cathodic background signal to an anodic response signal, which thus enabled the photoelectrochemical immunoassay of NSE. As shown in Figure a, the electrode exhibited a cathodic photocurrent of approximately −0.49 μA in the absence of NSE.…”

Polymer Dot-Gated Accumulation-Type Organic Photoelectrochemical Transistor for Urea Biosensing

“…The underlying mechanism of this behavior can be revealed by the potential distribution diagram, as described in Figure 3f. 30,31 In the ionic circuit, the two electric double layers (EDL) at the gate/electrolyte (G/E) and channel/ electrolyte (C/E) interfaces were equivalent to serial capacitors (C G and C C ). In the absence of light, the applied potential would drop upon them with…”

“…Upon light illumination, both curves clearly moved toward a higher level, but the presence of urea induced a much smaller shift (red dashed line) as compared to that without urea (black dashed line). The underlying mechanism of this behavior can be revealed by the potential distribution diagram, as described in Figure f. , In the ionic circuit, the two electric double layers (EDL) at the gate/electrolyte (G/E) and channel/electrolyte (C/E) interfaces were equivalent to serial capacitors ( C G and C C ). In the absence of light, the applied potential would drop upon them with V normalG / normalE = γ 1 + γ V normalG and V normalC / normalE = 1 1 + γ V normalG ( γ = C normalC C normalG ), respectively.…”

Hybridization Chain Reaction-Enhanced Biocatalytic Precipitation on Flower-like Bi2S3: Toward Organic Photoelectrochemical Transistor Aptasensing with High Transconductance

“…Upon light stimulation, the on-demand generation of a photovoltage ( V p ) on the PG could effectively redistribute the potential drop across the two capacitors and thus modulate the transistor response. Such photogating bridging the PEC processes and organic electronics has recently demonstrated its desirable potential in biosensors − and opto-logic circuits. , Despite its attractive perspective, the full potential of OPECT remains largely untapped due to its short development time. For example, an OPECT with high transconductance ( g m = Δ I DS /Δ V G ), the index of the device’s sensitivity, has been rarely reported.…”