Optofluidic paper-based analytical device for discriminative detection of organic substances via digital color coding

Area of Science:

• Optofluidics
• Analytical Chemistry
• Materials Science

Background:

• On-site detection of unknown chemical substances requires portable, affordable, sensitive, and selective methods.
• Mimicking biological systems like the olfactory system offers a promising approach for chemical discrimination.

Purpose of the Study:

• To develop an optofluidic paper-based analytical device (PAD) for portable and scalable detection and discrimination of organic chemicals.
• To integrate a macromolecule-driven flow (MDF) gate with photonic crystal (PhC) coding units for visual chemical identification.

Main Methods:

• Fabrication of an optofluidic PAD using a three-dimensional (3D) microfluidic paper integrated with two PhC coding units within a 3D-printed cartridge.
• Utilizing an MDF gate for precise control of liquid analyte flow based on intermolecular interactions.
• Employing PhC coding units to generate differential optical patterns for result visualization.

Main Results:

• The optofluidic PAD successfully distinguished 11 different organic chemicals.
• Digital readout was achieved through pattern recognition of colorimetric signals.
• The device demonstrated portable and scalable chemical detection capabilities.

Conclusions:

• The developed optofluidic PAD, mimicking the olfactory system, provides a novel strategy for visual chemical detection.
• This technology holds significant potential for colorimetric monitoring of environmental chemicals.