# Graphene Oxide and Conductive Polymer–Enhanced Langmuir–Blodgett Biosensor for Sensitive Detection of Pyrocatechol

## TL;DR

This paper introduces a new biosensor using graphene oxide and conductive polymers to detect pyrocatechol with high sensitivity and stability.

## Contribution

The novel hybrid Langmuir-Blodgett film integrates graphene oxide, conductive polymer, and enzyme for enhanced biosensing performance.

## Key findings

- Graphene oxide improves film compactness and enzyme-polymer-lipid stability.
- The biosensor shows nearly 2-fold higher sensitivity and lower detection limits.
- Synergy between components enhances redox cycling of pyrocatechol.

## Abstract

In this work, we report a novel Langmuir–Blodgett
(LB) biosensing
platform for the detection of phenolic compounds, using Pyrocatechol
as a model analyte. Although LB films have long been explored for
polyphenol detection, the present study introduces an innovative hybrid
architecture that integrates a lipid matrix (DMPA), a conductive polymer
(P3HT), graphene oxide (GO), and laccase into a single, highly organized
ultrathin film. This configuration simultaneously enhances film rigidity,
reduces surface roughness, and modulates electron-transfer properties
in a way not previously reported for LB-based enzymatic sensors. Comprehensive
interfacial characterization (surface pressure–area isotherms,
dilatational rheology, UV–Vis, AFM) reveals that GO plays a
decisive role in promoting compact molecular packing and stabilizing
the enzyme–polymer–lipid assembly. As a consequence,
the resulting LB films exhibit significantly improved electrochemical
performance, including nearly 2-fold higher sensitivity, lower detection
limits, and reduced overpotentials compared with films lacking GO.
The study also provides mechanistic evidence that the synergy between
conductive polymer domains, GO nanosheets, and the immobilized enzyme
facilitates more efficient redox cycling of Pyrocatechol. These findings
demonstrate that the rational incorporation of GO into LB enzymatic
architectures offers a promising route toward next-generation ultrathin
biosensors with enhanced analytical performance and structural stability.