Electrochemical Boron Detection with Ferrocene and Catechol-Functionalized Cyclodextrin Inclusion Complex.

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Supramolecular Chemistry

Background:

• Boron detection is crucial for environmental monitoring and water quality assessment.
• Existing methods for boron detection can be complex or lack sensitivity.
• Electrochemical methods offer potential for rapid and sensitive analyte detection.

Purpose of the Study:

• To develop a rapid and sensitive boron detection method using supramolecular interactions and electrochemical signal amplification.
• To investigate the mechanism of boron interaction with a functionalized cyclodextrin-ferrocene complex.
• To establish optimal conditions and assess the performance of the developed boron sensor.

Main Methods:

• Cyclic voltammetry (CV) measurements of ferrocene/catechol-functionalized β-cyclodextrin inclusion complexes.
• Utilizing an EC' reaction for current amplification.
• Investigating the effect of boric acid addition on the amplified electrochemical signal.
• Optimizing cyclodextrin (CyD) functionalization sites and measurement conditions.

Main Results:

• A sensitive boron detection method with a limit of detection of 0.16 mg B L⁻¹ was achieved using ferrocene/3,4-dihydroxybenzoic acid-β-cyclodextrin (Fc/3,4-DHBA-β-CyD).
• Boric acid addition decreased the amplified current due to ester formation with the diol structure and ferrocene.
• The binding constant for the interaction between Fc/3,4-DHBA-β-CyD and boric acid was estimated at ~1500 M⁻¹.
• The sensor demonstrated good recoveries in spiked real samples and was unaffected by other ions.
• The 3,4-DHBA-β-CyD solution showed excellent stability over 112 days.

Conclusions:

• The developed electrochemical sensor provides a rapid, sensitive, and selective method for boron detection in aqueous samples.
• Supramolecular interactions and EC' reactions are effective for amplifying electrochemical signals for analyte sensing.
• The Fc/3,4-DHBA-β-CyD system shows promise for practical boron monitoring applications.