Fluorescent polymer sensor array for detection and discrimination of explosives in water

Area of Science:

• Analytical Chemistry
• Materials Science
• Chemical Sensing

Background:

• Fluorescent polymer sensor arrays (FPSAs) offer potential for detecting various chemical analytes.
• Distinguishing between electron-withdrawing compounds (EWCs) and non-electron-withdrawing compounds is crucial for specific analyte detection.

Purpose of the Study:

• To develop and evaluate a fluorescent polymer sensor array (FPSA) for discriminating between different analytes in aqueous solutions.
• To assess the FPSA's ability to selectively detect explosives and explosive-related compounds (ERCs).

Main Methods:

• Fabrication of an FPSA using commercially available fluorescent polymers coated onto glass beads.
• Exposure of the array to 17 diverse analytes, including explosives (TNT, RDX), ERCs, and non-explosive EWCs.
• Analysis of response signatures using principal component analysis (PCA) and classification via linear discriminant analysis (LDA).

Main Results:

• The FPSA demonstrated natural selectivity towards EWCs.
• 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), a non-electron-withdrawing explosive, produced no response and was classified as a blank.
• Excellent discrimination was achieved for most compounds, including distinguishing between dinitrobenzene isomers, with exceptions for nitrotoluene and aminodinitrotoluene isomers.

Conclusions:

• The FPSA exhibits inherent selectivity for EWCs, enabling differentiation from non-EWC explosives.
• The array's ability to discriminate between various EWCs suggests potential for developing sensors with low false alarm rates.
• This technology could be applied to create advanced sensors for explosives and ERCs detection.