Smartphone-Enabled Colorimetric Trinitrotoluene Detection Using Amine-Trapped Polydimethylsiloxane Membranes.

Area of Science:

• Analytical Chemistry
• Materials Science
• Environmental Science

Background:

• 2,4,6-trinitrotoluene (TNT) is a hazardous explosive compound requiring sensitive detection methods.
• Existing TNT detection methods can be complex, time-consuming, and not suitable for field applications.
• Polydimethylsiloxane (PDMS) offers a versatile platform for chemical sensing applications.

Purpose of the Study:

• To develop a portable and user-friendly smartphone-enabled platform for the colorimetric analysis of TNT.
• To utilize amine-trapped PDMS as a sensing material for rapid TNT detection.
• To enable precise quantification of TNT in real-world environmental samples.

Main Methods:

• Preparation of amine-trapped PDMS by immersing cured PDMS in aminosilane solutions.
• Colorimetric analysis of TNT by observing color change in amine-trapped PDMS upon contact with TNT solutions.
• Optimization of amine-trapped PDMS for sensitive TNT detection (down to 1 μM).
• Development of a smartphone application to analyze color changes using the integrated camera for quantification.
• Demonstration of TNT detection in various water samples (drinking, tap, lake water).

Main Results:

• Amine-trapped PDMS exhibited a rapid and visible colorimetric response to TNT.
• The optimized PDMS material achieved a detection limit as low as 1 μM for TNT.
• The smartphone application enabled precise quantification of TNT concentrations.
• Successful detection of TNT in real environmental water samples was demonstrated.

Conclusions:

• The developed smartphone-enabled colorimetric method using amine-trapped PDMS provides a convenient and efficient approach for portable TNT detection.
• This system is suitable for field applications, offering rapid and accurate analysis of TNT.
• The study highlights the potential of amine-trapped PDMS in developing low-cost, portable sensing devices for environmental monitoring.