An affordable, field-deployable detecting system for cyanide ion - Investigating applications in real time uses

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Cyanide is a highly toxic pollutant with a low tolerable limit in drinking water.
• Developing sensitive and selective detection methods for cyanide is crucial for environmental and health monitoring.
• Fluorescent probes offer advantages in sensitivity, selectivity, and real-time detection.

Purpose of the Study:

• To synthesize and characterize novel fluorescent probes for the instantaneous visualization of cyanide ions.
• To investigate the sensing mechanism and evaluate the detection performance of the developed probes.
• To demonstrate the practical applicability of the probes in real-world samples and with an electronic device.

Main Methods:

• Synthesis of julolidine-coumarin conjugate-based fluorescent probes with varying electron acceptor units.
• Spectroscopic analysis (UV-Vis, fluorescence) to study probe response to cyanide.
• Investigation of probe-cyanide interaction mechanism using 1H NMR and the Intramolecular Charge Transfer (ICT) process.
• Determination of the limit of detection (LOD) and selectivity studies.
• Application of probes in real samples (cassava powder, potatoes, water) and integration with an Arduino device.

Main Results:

• The synthesized probes exhibited significant color changes under normal and UV light upon interaction with cyanide.
• The probe's sensing mechanism was confirmed to be based on the ICT process and nucleophilic addition reaction.
• A low detection limit in the nanomolar (nM) range was achieved, well below the tolerable level of 1.9 μM.
• The probes successfully detected cyanide in various real-world samples and were integrated with an electronic detection system.
• High sensitivity and selectivity for cyanide detection were demonstrated.

Conclusions:

• Novel fluorescent probes based on julolidine-coumarin conjugates were successfully developed for sensitive and selective cyanide detection.
• The probes offer a rapid, visual, and quantitative method for cyanide monitoring in environmental and food samples.
• The integration with an Arduino device highlights the potential for developing portable and user-friendly cyanide detection systems.