Ultrasensitive and Selective Fluorescent Sensor for 5-Hydroxymethylfurfural Based on a Molecularly Imprinted...

Area of Science:

• Analytical Chemistry
• Materials Science
• Nanotechnology

Background:

• 5-hydroxymethylfurfural (HMF) is a key indicator of food processing and storage.
• Accurate and selective detection of HMF is crucial for food quality control.
• Existing detection methods may lack sensitivity, selectivity, or practicality for real-world applications.

Purpose of the Study:

• To develop a highly selective and sensitive fluorescence sensor for 5-hydroxymethylfurfural (HMF) determination.
• To utilize nitrogen-doped graphene quantum dots confined in a metal-organic framework and molecularly imprinted polymer (MIP) for enhanced sensing.
• To validate the sensor's performance in complex food matrices.

Main Methods:

• Synthesis of nitrogen-doped graphene quantum dots (N-GQDs) integrated within a metal-organic framework (MOF).
• Fabrication of a molecularly imprinted polymer (MIP) layer for selective HMF recognition.
• Characterization using SEM, STEM, BET, FT-IR, and XRD.
• Fluorescence quenching mechanism based on photoinduced electron transfer (PET) for HMF detection.

Main Results:

• Successful synthesis and imprinting confirmed by characterization techniques.
• The sensor exhibited intense fluorescence quenched by HMF via PET.
• Linear response observed up to 35 µmol L^-1 with a low detection limit of 30 nmol L^-1.
• High selectivity, stability, and anti-interference capabilities demonstrated.
• Excellent recovery rates in real food samples (honey, juice, coffee).

Conclusions:

• The developed N-GQDs/MOF/MIP fluorescence sensor offers a robust platform for selective HMF detection.
• The sensor exhibits superior performance characteristics, including high sensitivity and selectivity.
• The practical applicability for real-world HMF monitoring in food products is confirmed.