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Published on: August 19, 2013
Bisphenol-based cyanide sensing: Selectivity, reversibility, facile synthesis, bilateral "OFF-ON" fluorescence, C2ν
Zakir Ullah1, Prasad M Sonawane2, Thien S Nguyen3
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea; Graduate School of Energy, Environment, Water and Sustainability (EEWS), KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
A novel sensor detects cyanide (CN-) in water with high selectivity and sensitivity. This reusable sensor, usable with smartphone apps, offers a cost-effective method for on-site environmental monitoring.
Area of Science:
- Chemical Sensing
- Materials Science
- Environmental Chemistry
Background:
- Cyanide (CN-) is a highly toxic pollutant with strict regulatory limits in drinking water.
- Developing selective and sensitive detection methods for cyanide is crucial for environmental safety and public health.
- Existing detection methods can be complex, costly, or unsuitable for on-site applications.
Purpose of the Study:
- To synthesize and characterize a novel dual-pocketed tetra-conjugated bisphenol-based chromophore for cyanide detection.
- To evaluate the sensor's selectivity, sensitivity, and reusability for cyanide ions.
- To demonstrate the practical application of the sensor for on-site, cost-effective cyanide monitoring.
Main Methods:
- Gram-scale synthesis of a novel bisphenol-based chromophore.
- Spectroscopic characterization including fluorescence spectroscopy, 1H NMR, and DFT calculations.
- Interferent testing and determination of detection limit for cyanide ions in DMSO/H2O.
- Fabrication of sensor interfaces on cotton swabs, Petri dishes, and filter papers.
- Smartphone-assisted colorimetric analysis using a "Color Picker" app.
Main Results:
- A novel chromophore with fluorescence at 652 nm was synthesized in ~90% yield.
- Highly selective, naked-eye detection of cyanide ions was achieved with a low detection limit of 0.38 µM.
- The sensor demonstrated excellent selectivity against common interferents.
- The sensor exhibited reversibility, indicating potential for reusability.
- Successful application demonstrations on various cost-effective, on-site platforms, including smartphone integration.
Conclusions:
- The developed bisphenol-based chromophore serves as an effective and selective sensor for cyanide detection.
- The sensor's low detection limit and reusability meet WHO guidelines for drinking water.
- The practical, cost-effective, and smartphone-compatible design facilitates on-site environmental monitoring of cyanide pollution.
