Gold Nanoparticles-Functionalized Cotton as Promising Flexible and Green Substrate for Impedometric VOC Detection

Area of Science:

• Nanomaterials Science
• Chemical Sensing
• Wearable Technology

Background:

• Development of sensitive and selective sensors for volatile organic compounds (VOCs) is crucial for disease diagnosis.
• Flexible and wearable sensor platforms offer potential for continuous health monitoring.
• Gold nanoparticles (Au NPs) exhibit unique electronic properties suitable for sensor applications.

Purpose of the Study:

• To investigate the application of gold nanoparticles functionalized on flexible cotton fabric as substrates for detecting acetone and ethanol.
• To characterize the structural, morphological, and dielectric properties of the functionalized fabric.
• To evaluate the sensing performance of the developed material using electrochemical impedance spectroscopy.

Main Methods:

• Synthesis of citrate- and polyvinylpyrrolidone (PVP)-functionalized gold nanoparticles (Au NPs).
• Deposition of Au NPs onto cotton fabric.
• Structural and morphological characterization using UV-VIS, FT-IR, AFM, and SEM.
• Dielectric characterization and electrochemical impedance spectroscopy (EIS) for VOC sensing.

Main Results:

• Citrate functionalization led to uniform Au NP distribution, facilitating electron transport and enhancing sensing capabilities.
• PVP functionalization created a more insulating matrix, increasing resistance but affecting NP interconnection.
• EIS measurements demonstrated the ability to distinguish between ethanol and acetone based on hydrogen bonding and proton migration impedance.

Conclusions:

• Flexible cotton fabric functionalized with gold nanoparticles shows promise as a sensitive substrate for VOC detection.
• The developed sensor platform can differentiate between ethanol and acetone, paving the way for breath analysis.
• This technology could lead to low-cost, wearable sensors for early disease diagnosis and personal protective equipment.