Rapid redox-response featured visual ascorbic acid sensor based on simple-assembled europium metal-organic framework

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Ascorbic acid (AA) is a vital biomolecule with diverse physiological roles.
• Accurate and rapid detection of AA is crucial for biomedical research and the food industry.
• Existing AA detection methods often lack sensitivity, speed, or simplicity.

Purpose of the Study:

• To develop a facile, fast, and visible sensing platform for ascorbic acid (AA) detection.
• To synthesize and characterize a novel hydrangea-like europium metal-organic framework (HL-EuMOF).
• To integrate the sensor with smartphone technology for practical AA quantification.

Main Methods:

• Synthesis of HL-EuMOF via a one-step room temperature process using Eu³⁺ and 1,10-phenanthroline-2,9-dicarboxylic acid.
• Fabrication of HL-EuMOF@Fe³⁺ for a "turn-off" fluorescence sensing mechanism based on the redox reaction with AA.
• Utilizing smartphone-assisted RGB analysis for visible and quantitative AA determination.

Main Results:

• The synthesized HL-EuMOF exhibited strong red fluorescence, a long decay lifetime (548.623 μs), and good luminescent stability.
• The HL-EuMOF@Fe³⁺ sensor demonstrated a low detection limit (31.94 nM) and a rapid response time (30 s) with high selectivity.
• The sensor performed effectively in complex matrices like human serum and beverages.

Conclusions:

• A novel HL-EuMOF-based sensor provides a sensitive, selective, and rapid method for AA detection.
• The integration with smartphone technology allows for convenient and visible quantitative analysis of AA.
• This platform holds significant potential for AA monitoring in biomedical and food industry applications.