Fluorescent imprinted polymer sensors for chiral amines

Area of Science:

• Polymer Chemistry
• Analytical Chemistry
• Organic Chemistry

Background:

• Fluorescent sensors based on molecularly imprinted polymers (MIPs) require moieties with significant fluorescence changes upon analyte binding.
• Chiral amines are crucial in pharmaceuticals, necessitating selective detection methods.

Purpose of the Study:

• To design and synthesize novel polymerizable coumarin monomers for fluorescent MIP sensors.
• To develop MIP-based fluorescent sensors for the selective detection of chiral amines, specifically ephedrine enantiomers.

Main Methods:

• Synthesis of two novel coumarin monomers: 6-styrylcoumarin-4-carboxylic acid (SCC) and 6-vinylcoumarin-4-carboxylic acid (VCC).
• Preparation of MIPs using SCC or VCC with (-)-ephedrine as the template and ethylene glycol dimethacrylate as the cross-linker.
• Evaluation of fluorescence changes in response to amine binding in acetonitrile and aqueous buffers at varying pH.

Main Results:

• MIPs prepared with SCC and VCC showed a decrease in fluorescence upon amine binding in acetonitrile, with selectivity for (-)-ephedrine over its enantiomer (+)-ephedrine.
• The fluorescence response of SCC-based MIPs to (-)-ephedrine differed in direction compared to solution-phase recognition.
• Non-imprinted polymers (NIPs) exhibited reduced response and no resolving power, confirming successful imprinting and selective binding sites.

Conclusions:

• Novel coumarin monomers SCC and VCC enable the creation of effective fluorescent MIP sensors for chiral amines.
• The developed MIPs demonstrate selective recognition capabilities for pharmaceutical compounds like ephedrine enantiomers.
• The study highlights the potential of these MIPs for sensitive and selective chiral amine detection in various media.