Synergistic non-covalent-recognition-enabled highly efficient through-space charge transfer for specific synthetic...

Area of Science:

• Analytical Chemistry
• Chemical Sensing
• Materials Science

Background:

• Detecting analytes with low chemical reactivity is challenging due to the lack of effective covalent reaction pathways.
• Synthetic cannabinoids like EG-2201 require sensitive and specific detection methods.

Purpose of the Study:

• To develop a fluorescent probe for specific and precise trace-level detection of the synthetic cannabinoid EG-2201.
• To investigate a sensing strategy based on synergistic non-covalent interactions and intermolecular charge transfer.

Main Methods:

• A naphthalimide-based fluorescent probe was designed to interact with EG-2201 via multiple non-covalent interactions.
• A ratiometric fluorescence sensing system was constructed based on probe aggregate dissociation and charge transfer.
• A probe-anchored sensing film was integrated into a portable device (Drugs Analyst) for visual detection.

Main Results:

• The probe exhibited a distinct green-to-yellow fluorescence response upon EG-2201 binding.
• The sensing system achieved a low limit of detection (0.4 µM), rapid response (2 s), and high anti-interference capabilities.
• Visual detection of EG-2201 in various adulterated samples was successfully demonstrated, regardless of sample complexity.

Conclusions:

• This study presents a novel fluorescent probe strategy for detecting low-reactivity analytes like EG-2201.
• Non-covalent interactions can effectively drive sensing recognition by enhancing targeted spectral-charge transfer (TSCT) efficiency.
• The developed system offers a promising tool for rapid and accurate on-site detection of synthetic cannabinoids.