A New Boron-Rhodamine-Containing Carboxylic Acid as a Sugar Chemosensor

Area of Science:

• Chemical Sensing
• Organic Chemistry
• Materials Science

Background:

• Development of selective and sensitive chemosensors is crucial for biological and environmental monitoring.
• Boron-based compounds offer unique properties for molecular recognition.
• Rhodamine derivatives are known for their fluorescent characteristics.

Purpose of the Study:

• To synthesize and characterize a novel boron-rhodamine-containing carboxylic acid (BRhoC) as a potential sugar chemosensor.
• To investigate the sensing mechanism of BRhoC towards different sugars.
• To evaluate the performance of BRhoC in terms of sensitivity and selectivity.

Main Methods:

• Friedel-Crafts reaction and chloranil oxidation were employed for BRhoC synthesis.
• UV-Vis absorption and fluorescence spectroscopy were used to study BRhoC's optical properties.
• Binding constants were determined by analyzing spectral changes upon sugar addition.

Main Results:

• BRhoC exhibits strong absorption at 621 nm and emission at 644 nm with a high molar absorption coefficient.
• The borinate group of BRhoC forms cyclic esters with sugar diols, inducing spectral shifts.
• BRhoC showed selective binding to D-fructose (K = 2.3 × 10^2 M^-1) over D-glucose (K = 3.1 M^-1).

Conclusions:

• BRhoC is a promising fluorescent chemosensor for sugar detection.
• Its sugar-binding capability and carboxylic acid group make it suitable for advanced sensor fabrication.
• This work contributes to the development of novel optical sensors for saccharides.