A portable paper-based and smartphone-assisted colorimetric sensor for copper oxychloride

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Environmental Science

Background:

• Copper oxychloride (CuOxy) is a widely used fungicide and bactericide in agriculture.
• Maximum Residue Limits (MRLs) for CuOxy are regulated by authorities like EFSA, necessitating accurate monitoring.
• Existing detection methods may lack the speed, sensitivity, or on-site applicability required for real-time food safety assessments.

Purpose of the Study:

• To develop a novel, highly sensitive colorimetric sensor for copper oxychloride (CuOxy) detection.
• To integrate this sensor with AI-assisted smartphone technology and paper-based analytical devices (PADs) for on-site analysis.
• To validate the sensor's performance and applicability in real-world environmental and food samples.

Main Methods:

• Synthesis of coumarin triazole-functionalized silver nanoparticles (CT-AgNPs).
• Development of a colorimetric assay for CuOxy detection using CT-AgNPs.
• Integration of the sensor with smartphone imaging and PADs for AI-assisted analysis.
• Testing on environmental samples (water) and food matrices (fruits, vegetables).

Main Results:

• The CT-AgNPs sensor achieved a low limit of detection (LoD) of 0.007 µM and a linear detection range (LDR) of 0.1-100 µM.
• The system demonstrated high selectivity, with no significant interference from common environmental contaminants.
• Successful application in real samples (tap water, river water, fruits, vegetables) with high recovery rates.

Conclusions:

• A novel CT-AgNPs-based colorimetric sensor enables rapid, selective, and sensitive detection of CuOxy.
• The integration with AI-assisted smartphone and PADs provides a portable platform for on-site monitoring.
• This technology offers a promising solution for ensuring food safety and environmental health through effective CuOxy residue analysis.