Gold Nanoparticle-Based Colorimetric Assay for Selenium Detection via Hydride Generation

Area of Science:

• Nanotechnology
• Analytical Chemistry
• Environmental Science

Background:

• Gold nanoparticles (AuNPs) enable naked-eye colorimetric assays for molecular events.
• Traditional AuNP assays suffer from sample matrix interference, affecting ionic strength and causing undesirable aggregation.
• Existing methods lack selectivity due to liquid-phase molecular recognition.

Purpose of the Study:

• To develop a novel gold nanoparticle-based colorimetric assay for selenium detection.
• To eliminate sample matrix interference by converting selenium to hydride chemical vapor (H2Se).
• To enhance selectivity and sensitivity for selenium determination in complex samples.

Main Methods:

• Selenium was converted to its hydride chemical vapor (H2Se).
• H2Se gas was delivered into a solution of gold nanoparticles (AuNPs) to induce a color change.
• UV-vis spectroscopy and naked-eye observation were used for detection.

Main Results:

• The hydride generation method eliminated sample matrix interference, ensuring excellent selectivity.
• The assay achieved a detection limit of 0.05 μM using UV-vis detection.
• A detection limit of 1 μM was achievable with naked-eye observation.
• The method was successfully applied to detect selenium in biological and environmental samples.

Conclusions:

• The proposed AuNP colorimetric assay with hydride generation offers a highly selective and sensitive method for selenium detection.
• This approach effectively mitigates interference from sample matrices like high salinity.
• The method demonstrates practical applicability for real-world selenium analysis in diverse sample types.