Sensing Techniques for Organochlorides through Intermolecular Interaction with Bicyclic Amidines

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Sensing Technology

Background:

• Organochloride compounds are prevalent industrial chemicals, posing environmental risks.
• Their high volatility complicates direct detection in environmental samples.
• Existing detection methods often lack the required sensitivity and simplicity.

Purpose of the Study:

• To introduce a novel, simplified sensing mechanism for toxic organochlorides.
• To enhance detection sensitivity for organochlorides in environmental matrices.
• To investigate the conjugation chemistry of 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) with organochlorides.

Main Methods:

• Utilized nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometry (LC-MS) to study DBN conjugation.
• Employed colorimetric assays and micellar electrokinetic chromatography (MEKC) to determine labeling yield and detection limits.
• Investigated the interaction of DBN with trichloroethylene (TCE), dichloromethane (DCM), and dichlorodiphenyltrichloroethane (DDT).

Main Results:

• DBN labeling on organochlorides was confirmed via chlorine-nitrogen interaction using NMR and LC-MS.
• The DBN-labeling method demonstrated high sensitivity, with TCE detected at picomolar levels.
• TCE detection limits were significantly lower (two orders of magnitude) than EPA maximum contaminant levels.

Conclusions:

• DBN provides a viable labeling agent for sensitive organochloride detection.
• The DBN-labeling method, coupled with MEKC, offers a highly sensitive sensing platform.
• This approach facilitates the development of field-deployable devices for monitoring toxic organochlorides.