A Versatile Colorimetric Probe based on Thiosemicarbazide-Amine Proton Transfer.

Area of Science:

• Analytical Chemistry
• Organic Chemistry
• Materials Science

Background:

• Amines are crucial industrial chemicals and biological markers.
• Rapid and efficient detection methods for amines are in high demand.
• Existing detection methods may lack sensitivity or broad applicability.

Purpose of the Study:

• To develop novel, highly sensitive sensor molecules for amine detection.
• To investigate the mechanism of amine binding and signal transduction.
• To demonstrate the practical application of the developed sensors.

Main Methods:

• Synthesized sensor molecules by coupling a thiosemicarbazide binding motif with a naphthalimide chromophore.
• Investigated the amine binding mechanism using spectroscopic techniques.
• Fabricated indicator paper for practical amine detection.

Main Results:

• The sensor molecules exhibited a pronounced and visible color change upon amine detection.
• The binding mechanism was confirmed to involve proton transfer from thiosemicarbazide to the amine analyte.
• Indicator paper successfully detected volatile amines at concentrations as low as 10 ppm.

Conclusions:

• The developed thiosemicarbazide-naphthalimide sensors offer high sensitivity and a clear visual response for amine detection.
• The proton transfer mechanism ensures broad applicability and high sensitivity.
• The indicator paper format demonstrates the practical utility of these sensors for detecting volatile amines.