Ultrafast and Efficient Detection of Formaldehyde in Aqueous Solutions Using Chitosan-based Fluorescent Polymers

Area of Science:

• Analytical Chemistry
• Polymer Science
• Environmental Science

Background:

• Formaldehyde (HCHO) is a toxic pollutant found in aquatic food due to illicit addition or improper storage.
• Existing small-molecule fluorescent probes for HCHO suffer from low sensitivity and slow response times.
• There is a need for improved sensors for accurate and rapid HCHO detection.

Purpose of the Study:

• To develop a novel polymeric fluorescent probe for sensitive and ultrafast detection of formaldehyde.
• To overcome the limitations of sensitivity and response time associated with current HCHO detection methods.
• To apply the developed probe for real-world analysis of formaldehyde in food and water.

Main Methods:

• A hydrazino-naphthalimide-functionalized chitosan (HN-Chitosan) polymeric probe was synthesized.
• The probe utilizes the specific reaction between HCHO and hydrazino-naphthalimide groups for a "turn-on" fluorescence response.
• Cooperative binding effects of the polymer enhanced HCHO enrichment and reaction acceleration.

Main Results:

• The HN-Chitosan probe demonstrated an ultrafast equilibrium fluorescence response in less than 1 minute.
• High sensitivity and selectivity for formaldehyde detection were achieved.
• The probe was successfully applied to analyze formaldehyde in real-world food and water samples.

Conclusions:

• The developed HN-Chitosan polymeric probe offers a significant advancement in formaldehyde detection.
• The probe provides a sensitive, selective, and rapid method for analyzing HCHO in environmental and food samples.
• The modular design strategy is applicable for developing polymeric probes for other pollutants.