Electrophilicity Modulation for Sub-ppm Visualization and Discrimination of EDA

Area of Science:

• Analytical Chemistry
• Chemical Sensing
• Environmental Monitoring

Background:

• Accurate detection of hazardous chemicals like organic amines is vital for public safety and environmental protection.
• Existing methods struggle with sensitive and specific differentiation of structurally similar organic amines.
• Ethylenediamine (EDA) detection poses challenges due to its widespread use and potential hazards.

Purpose of the Study:

• To develop a novel optical probe for rapid, ultra-sensitive, and ratiometric fluorescence detection of ethylenediamine (EDA).
• To achieve specific recognition of EDA, distinguishing it from structural analogs and potential interferents.
• To integrate the probe with a portable sensing chip and AI for practical, low-concentration discrimination.

Main Methods:

• Design and synthesis of a unique optical probe with two electrophilic recognition sites.
• Ratiometric fluorescence spectroscopy for sensitive and selective EDA quantification.
• Testing probe sensitivity, specificity against 28 interferents, and response time.
• Integration with a portable sensing chip and application of a convolutional neural network (CNN) algorithm for image processing and discrimination.

Main Results:

• The probe demonstrated ppb/nmol level sensitivity for both liquidous and gaseous EDA.
• Specific recognition of EDA was achieved, with no interference from 28 common substances.
• A rapid fluorescence response time of less than 0.2 seconds was observed.
• The combined system successfully discriminated EDA from non-targets at extremely low concentrations.

Conclusions:

• The developed optical probe offers a highly sensitive and selective method for EDA detection.
• The ratiometric fluorescence approach provides intuitive and distinct signals for differentiation.
• Integration with AI-powered image processing enables precise discrimination in practical sensing applications.
• This technology holds significant potential for real-time monitoring and safeguarding against hazardous chemical exposure.