Work

Nanocomposite-Based Dual Electrochemical Immunosensor for Simultaneous Detection of Intestinal Barrier Biomarkers: Intestinal Fatty Acid Binding Protein and Fecal Calprotectin

Year: 2026

Type: article

Abstract: Disruption of the intestinal barrier is a hallmark of inflammatory bowel disease (IBD) and drives both epithelial injury and neutrophil-mediated inflammation, yet rapid, multiplexed assessment of these processes remains an unmet clinical need. Intestinal fatty acid binding protein (iFABP) and fecal calprotectin (FC) provide complementary insights into barrier integrity and mucosal inflammation, but conventional ELISA-based assays are time-consuming, low-throughput, and require large sample volumes. Here, we introduce a dual electrochemical sandwich immunosensor enabling simultaneous quantification of iFABP and FC on screen-printed dual carbon electrodes (SPdCEs). Capture antibodies were immobilized via electrografting of p-aminobenzoic acid diazonium salt, while a V2O5/MWCNTs-HRP–streptavidin nanocomposite amplified the electrocatalytic reduction in hydrogen peroxide, enhancing sensitivity. The platform achieved detection limits of 0.01 pg mL−1 (iFABP) and 1 pg mL−1 (FC) with a total assay time of 1 h 20 min and sample volume of just 5 μL, outperforming conventional ELISA in speed and efficiency. High repeatability, reproducibility, and accurate recovery in enriched fecal samples confirmed analytical robustness. By integrating multiplexed detection, nanostructured signal amplification, and robust electrode engineering, this immunosensor provides a rapid, sensitive, and low-volume platform for point-of-care and decentralized monitoring of IBD, enabling timely clinical decision-making and longitudinal patient management.

Source: Biosensors

DOI: 10.3390/bios16040199

Authors: Lorena García-Rodrigo, Claudia Ramos-López, Esther Sánchez-Tirado, Lourdes Agüí, Araceli González-Cortés

Institution: Universidad Complutense de Madrid

Language: English

Topic: Electrochemical sensors and biosensors

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,654