Green extract rosemary acid as a viscosity-sensitive molecular sensor in liquid systems

Area of Science:

• Analytical Chemistry
• Materials Science
• Biochemistry

Background:

• Liquid micro-environments are critical for various processes, and their changes correlate with degradation in products like beverages.
• Monitoring local viscosity fluctuations is key to understanding micro-environmental status.
• Developing sensitive and selective sensors for viscosity is essential for quality control.

Purpose of the Study:

• To develop a versatile optical sensor for monitoring liquid micro-environmental viscosity.
• To utilize rosmarinic acid (RA), a natural product, as a fluorescent probe for viscosity sensing.
• To establish an in situ and visualization method for tracking liquid deterioration.

Main Methods:

• Extraction and characterization of rosmarinic acid (RA) from rosemary.
• Utilizing RA's fluorescence properties, including its Stokes shift and photostability.
• Applying fluorescence analytical techniques to monitor viscosity changes in various liquids.

Main Results:

• Rosmarinic acid (RA) demonstrated a large Stokes shift (123.8 nm) and excellent photostability.
• RA showed high selectivity and sensitivity for viscosity alterations in diverse commercial liquids.
• A 58-fold signal enhancement was observed in high-viscosity media, enabling sensitive detection.

Conclusions:

• Rosmarinic acid (RA) serves as an effective and sustainable fluorescent sensor for liquid viscosity.
• The developed method allows for in situ and visualized tracking of liquid deterioration.
• This research paves the way for natural product-based molecular tools in liquid safety inspection.