DNA Genotyping Based on Isothermal Amplification and Colorimetric Detection by Consumer Electronics Devices

Area of Science:

• Biomedical Engineering
• Molecular Diagnostics
• Consumer Electronics in Healthcare

Background:

• Point-of-care testing (POCT) for DNA biomarkers necessitates compact and accessible biosensing systems.
• Consumer electronic devices offer portability, mass-producible components, and high-performance readout capabilities ideal for novel bioanalytical methods.

Purpose of the Study:

• To describe DNA biomarker detection, specifically single nucleotide polymorphisms (SNPs), using consumer electronic devices.
• To demonstrate the feasibility of integrating Loop-mediated Isothermal Amplification (LAMP) with user-friendly optical devices for genetic analysis.

Main Methods:

• Detection of SNPs using optical devices like USB microscopes, flatbed scanners, smartphones, and DVD drives.
• Utilizing Loop-mediated Isothermal Amplification (LAMP) for allele-specific discrimination prior to optical detection.
• Two methods presented: hybridization to allele-specific probes on plastic chips and allele-specific primers with colorimetric detection in microfluidic chips.

Main Results:

• Consumer electronic devices achieved sensitive and precise measurements, including high signal-to-noise ratios, excellent image resolution, and reproducible scanning.
• The integrated DNA-based method demonstrated a low detection limit (100 genomic DNA copies), high specificity, and reproducibility (<15% variation).
• Assays were cost-effective (<€10/test), validated by reference methods, and suitable for genotyping clinically relevant SNPs from human samples.

Conclusions:

• Consumer electronic devices are effective for sensitive, precise, and reproducible DNA biomarker detection at the point-of-care.
• The integrated LAMP and consumer electronics approach offers a low-cost, user-friendly, and specific method for genetic analysis.
• Implementation in minimally specialized clinical laboratories is feasible, with potential for telemedicine integration due to connectivity and low cost.