Ultrasensitive Monitoring of Cyanide Concentrations in Water Using a Au_core-Ag_shell Hybrid-Coating-Based Fiber...

Area of Science:

• Nanomaterials Science
• Analytical Chemistry
• Environmental Monitoring

Background:

• Cyanides are highly toxic, inhibiting cellular respiration and posing risks in natural and industrial settings.
• Existing cyanide detection methods require improvement in sensitivity and simplicity for effective monitoring.
• The need for advanced sensors is critical due to the widespread presence and toxicity of cyanides.

Purpose of the Study:

• To develop ultrahigh-sensitive colorimetric and fiber optical sensors for simple cyanide monitoring.
• To chemically synthesize Au_core-Ag_shell hybrid nanomaterials for sensor applications.
• To investigate the sensing principle based on cyanocomplex formation and LSPR changes.

Main Methods:

• Synthesis of Au_core-Ag_shell hybrid nanomaterials with varying core/shell thicknesses.
• Development of LSPR-based colorimetric sensors utilizing optical absorbance changes.
• Immobilization of hybrid nanoparticles on fiber optics for quantitative cyanide detection.
• Analysis of cyanocomplex formation and its effect on refractive indices and LSPR properties.

Main Results:

• The colorimetric sensor detected cyanide down to 5 × 10^-6 M.
• The fiber optical sensor achieved an ultrahigh sensitivity with a detection limit of 8 × 10^-11 M.
• Cyanocomplex formation induced measurable changes in refractive indices and LSPR properties.

Conclusions:

• Au_core-Ag_shell hybrid nanomaterials enable the development of highly sensitive cyanide sensors.
• Fiber optical sensors offer superior sensitivity for quantitative cyanide detection compared to colorimetric methods.
• The developed sensors provide a simple and effective approach for ultrahigh-sensitive cyanide monitoring.