Signal-amplified microelectrode sensor for nucleic acid detection with reduced false readouts

Overview

This technology offers a novel electrochemical sensing platform that addresses a critical challenge in biosensing: reducing false positive and false negative readouts. Unlike traditional calibration approaches used in quantitative analysis, the platform employs a multi-parameter calibration and ratiometric analysis strategy that delivers high signal specificity for target analytes.

The system is designed for rapid, one-step measurements directly in biological matrices, providing both qualitative yes/no answers and absolute quantification without the multi-step sample treatments or amplification required by PCR-type methods. Key applications include detection of viral RNA sequences, microRNAs for disease diagnostics, and small molecule differentiation for pharmaceutical and agricultural testing. The technology is being adapted for plant nucleic acid detection, making it relevant for agricultural biotechnology and pathogen screening.

Technical specifications

Core sensing mechanism:

• Microelectrode or microelectrode array platform functionalized with designed nucleotide probes
• Signal-on mechanism through aptamer refolding structures that recognize target nucleic acid sequences with high specificity
• In-situ signal amplification via redox cycling on microelectrodes, eliminating the need for sample amplification
• Kinetics-based ratiometric analysis measuring multiple parameters from a single measurement

Validated performance characteristics:

• Response time in minutes with turnaround potential within 30 minutes
• Sensitivity at attomolar (aM) concentrations with dynamic range up to nanomolar (nM)
• Discrimination against one or two base mismatches in nucleic acid sequences
• Validated efficacy in mouse serum and synthetic urine for point-of-care applications
• Ratiometric dual-signal approach (electrochemiluminescence and current) demonstrated for differentiating analog small molecules at sub-nanomolar concentrations

Current prototype: Individual microelectrodes several to tens of microns in size, with planned development of arrays for high-throughput analysis.

Technology readiness level

The platform has been validated through published research and patented innovations for microRNA-122 detection and small molecule differentiation. Published work demonstrates efficacy in complex biological matrices including mouse serum and synthetic urine.

Current development focuses on adapting the technology for plant nucleic acid sequences. Practical milestones include fabricating and functionalizing microelectrodes specific to target nucleic acids, establishing tunable dynamic range with adequate sensitivity in laboratory tests, achieving one-step kinetics measurements within 30 minutes, and conducting efficacy tests in field-relevant crude sample extracts. The technology is at a stage suitable for collaborative development toward agricultural and diagnostic applications.