Gold nanoparticle chemiresistor sensor array that differentiates between hydrocarbon fuels dissolved in artificial...

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Gold nanoparticle films (Au(NPF)) offer unique surface properties for sensor development.
• Chemiresistor sensor arrays provide a platform for detecting complex mixtures.
• Functionalization of Au(NPF) with thiols allows for tailored analyte interactions.

Purpose of the Study:

• To develop and evaluate chemiresistor sensor arrays based on functionalized Au(NPF) for differentiating aqueous analytes.
• To determine the discrimination capabilities of the sensor arrays for linear alcohols and petroleum products.

Main Methods:

• Assembly of Au(NPF) chemiresistor sensor arrays functionalized with hydrophobic and hydrophilic thiols.
• Exposure of sensor arrays to varying concentrations of linear alcohols (methanol, ethanol, propan-1-ol, butan-1-ol) in water.
• Exposure of sensor arrays to crude oil, diesel, and gasoline mixtures in artificial seawater.
• Application of discriminant analysis to interpret sensor response patterns.

Main Results:

• The sensor array successfully distinguished between different alcohol solutions above 20 mM (200 mM for methanol).
• Concentrations below the discrimination limit showed inconsistent response patterns.
• The array accurately identified crude oil, diesel, and three gasoline varieties in artificial seawater.
• The study established the approximate limit of discrimination for the developed sensor system.

Conclusions:

• Functionalized Au(NPF) chemiresistor arrays can effectively differentiate complex analyte mixtures in aqueous phases.
• The pattern of responses from an array of differently functionalized sensors is key to analyte identification.
• This approach demonstrates a viable method for sensing and distinguishing various chemical compounds in water.