2D MoS2-based Flexible Optoelectronic for Biosensing

• NCJ Number: 310405
• Journal: Sensors and Actuators B: Chemical Volume: 439 Dated: 2025 Pages: 137848
• Author(s): Ying Chen; Tung Pham; Ashok Mulchandani
• Date Published: 2025
• Grant Number(s): 2019-NE-BX-0006
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)

Annotation

This paper reports on the research methodology and findings for a project that demonstrated the potential of biofunctionalized MoS₂-based flexible optoelectronics for identifying different biomolecules and biomarkers in advancing the early disease diagnostics.

Abstract

In this study, the authors present a flexible, optoelectronic molybdenum disulfide (MoS₂) based field-effect transistor (FET) biosensor designed for the real-time detection of human immunoglobulin G (HIgG) proteins in liquid-phase environments. To address the limitations of high resistivity and low output current typically associated with MoS₂-based FETs, they employed a photonic strategy integrating red light illumination (650 nm) precisely matched to the band gap of monolayer MoS₂. This strategy enhanced the device’s performance, achieving a 2.4-fold increase in sensitivity (0.115 per Log[ng/mL]) and reducing the limit of detection (LOD) from 85.9 ng/mL to 7.57 ng/mL under illumination. The biosensor was fabricated on a flexible Kapton substrate, enabling cost-effective production and compatibility with wearable diagnostics. An atomic layer deposited (ALD) aluminum oxide (Al₂O₃) passivation layer provided device protection and facilitated biofunctionalization with antibodies via linkers. Specific binding of HIgG proteins to the immobilized antibodies resulted in measurable changes in the output current, which were detected as the sensing signal. This platform demonstrated excellent specificity, negligible cross-reactivity with non-target proteins, and robust performance in both simple buffer solutions and complex artificial urine matrices. The MoS₂-based biosensor demonstrated durability with stable responses during extended static bending tests. By eliminating applied gate voltages and utilizing optoelectronic enhancement, this work advances energy-efficient, reliable, high-performance biosensors. It highlights the potential of biofunctionalized MoS₂ platforms for early disease diagnostics and future innovations in flexible, wearable biosensing technologies. (Published Abstract Provided)