DNA aptamer-based microbial detection using home medical test formats

Overview

This technology transforms widely available home medical test formats into practical tools for microbial contamination detection. By leveraging DNA aptamers—short, synthetic DNA sequences selected through a process called SELEX (Systematic Evolution of Ligands by Exponential Enrichment)—the platform selectively binds viable microorganisms while ignoring non-viable ones. Conjugating these aptamers to gold nanoparticles enables qualitative dipstick-style tests similar to pregnancy tests, while conjugating them to invertase (an enzyme that converts sucrose into glucose) enables quantitative readings on standard single-use or continuous-monitoring glucometers. Because the underlying test devices are already familiar to consumers, adoption barriers are significantly reduced compared to introducing entirely new diagnostic hardware.

Technical specifications

Key features:

• SELEX-based aptamer selection with counter-selection steps to ensure aptamers bind only viable, not non-viable, microorganisms
• Gold nanoparticle–aptamer conjugates for colorimetric dipstick tests producing visible results in a pregnancy-test-like format
• Invertase–aptamer conjugates that convert microbial binding events into measurable glucose signals for glucometer-based quantitative detection
• Low-cost, stable reagents — DNA aptamers are cheaper to produce and more shelf-stable than antibodies, and are generated in vitro rather than in animals
• Dual readout capability supporting both qualitative (yes/no) and quantitative (concentration) testing workflows
• Robustness validated by non-trained users to confirm usability outside specialized laboratory settings

Technology background: The development builds on demonstrated expertise in differentiating infectious from non-infectious viruses (including SARS-CoV-2), adapting aptamers into dipstick sensor formats, and pioneering the repurposing of glucometers as general-purpose quantitative health meters. Prior work has produced more than 250 peer-reviewed publications and more than 50 U.S. and international patents, with commercial products deployed in environmental monitoring and medical diagnostics across multiple countries.

Technology readiness level

The core aptamer selection methodology and dipstick sensor adaptation have been demonstrated in prior peer-reviewed work, including differentiation of infectious from non-infectious viruses. Current efforts focus on in vitro SELEX selection from a large DNA library (up to approximately 10^15 sequences) to generate microbe-specific aptamers, followed by sensor conversion and validation using spiked samples. Validation will assess detection speed, specificity, and detection limit on paper-based dipsticks, as well as quantitative performance on glucometer-based formats. Robustness testing by non-trained scientists is planned to confirm real-world usability. The technology is at an early-to-mid stage of development, with proven component methods advancing toward integrated sensor validation.