Additive manufacturing leveraged microfluidic setup for sample to answer colorimetric detection of pathogens

Area of Science:

• Biomedical Engineering
• Point-of-Care Diagnostics
• Molecular Assays

Background:

• Colorimetric detection integrated with loop-mediated isothermal amplification (LAMP) offers potential for point-of-care infectious disease diagnostics.
• Current methods face challenges in rapidity, user variability, signal quantification, and complex manual steps, limiting clinical application.

Purpose of the Study:

• To develop and validate a novel, automated, smartphone-operated system for rapid, colorimetric detection of infectious diseases.
• To address limitations of existing LAMP-based colorimetric assays, including speed, reproducibility, and ease of use.

Main Methods:

• An integrated system comprising an additively manufactured microfluidic cartridge, a portable reflected-light imaging setup with controlled epi-illumination (PRICE) module, and a control/data analysis module was designed.
• The microfluidic cartridge automates sample preparation, reagent mixing, and isothermal amplification using tunable elastomeric chambers and actuators.
• The PRICE module captures colorimetric changes on a plasmonic nanostructured substrate for quantitative analysis.

Main Results:

• The automated system successfully detected SARS-CoV-2 wild-type RNA.
• A rapid turnaround time of 13 minutes was achieved for nucleic acid detection.
• Individual components were characterized, demonstrating the feasibility of the integrated device.

Conclusions:

• The developed smartphone-operated automated setup offers a robust solution for rapid, point-of-care molecular diagnostics.
• This technology has the potential to be adapted for various molecular assays requiring sequential fluid handling.
• The system addresses key challenges, paving the way for improved infectious disease detection in resource-limited settings.