Hydrogel-Based Plasmonic Sensor Substrate for the Detection of Ethanol.

Area of Science:

• Analytical Chemistry
• Materials Science
• Biotechnology

Background:

• In-line monitoring of ethanol concentration is vital for breweries and distilleries.
• Current infrared spectroscopy methods are expensive and time-consuming, limiting accessibility for smaller businesses.

Purpose of the Study:

• To develop a compact, cost-effective sensor for real-time ethanol concentration monitoring.
• To overcome the limitations of existing spectroscopic techniques.

Main Methods:

• Utilized a nanostructured, plasmonically active sensor substrate coated with an ethanol-sensitive hydrogel (polyacrylamide/bisacrylamide).
• Measured ethanol concentration via changes in the refractive index induced by hydrogel swelling/shrinking.
• Employed a simple transmittance setup for detection.

Main Results:

• Demonstrated effective detection of ethanol concentrations from 0 to 30 vol%.
• Achieved a response time of 5.2 minutes, four times faster than other hydrogel-based sensors.
• Presented initial data on sensor longevity.

Conclusions:

• The developed hydrogel-based sensor offers a promising, affordable, and efficient solution for in-line ethanol monitoring.
• This technology can significantly benefit small and medium-sized enterprises in the beverage industry.
• Further research into sensor lifetime and optimization is warranted.