Ultrasensitive, Specific, and Rapid Fluorescence Turn-On Nitrite Sensor Enabled by Precisely Modulated Fluorophore...

Area of Science:

• Organic chemistry
• Materials science
• Analytical chemistry

Background:

• Precise regulation of fluorophore binding sites is crucial for designing functional fluorescent sensing materials.
• Organic probes are essential tools for detecting specific analytes with high sensitivity and selectivity.

Purpose of the Study:

• To design and synthesize a novel organic probe with specific fluorescence properties for sensitive nitrite detection.
• To investigate the structure-activity relationship of benzothiazole derivatives in nitrite sensing.
• To evaluate the performance of the developed probe for rapid, on-site nitrite measurement.

Main Methods:

• Synthesis of a unique 2-(2-amino-4-carboxyphenyl) benzothiazole (ortho-BT) derivative.
• Characterization of the probe's fluorescence properties and nitrite recognition mechanism.
• Evaluation of detection limit, response time, and specificity against various interfering substances.

Main Results:

• The ortho-BT probe specifically recognizes nitrite through the fluorophore bond at the ortho-position of the aniline moiety.
• The probe exhibits a low detection limit (2.2 fg) and rapid response time (<5 s).
• Exceptional specificity was demonstrated in the presence of over 40 diverse interfering substances, including redox-active compounds, colored substances, nitro compounds, and metal ions.

Conclusions:

• The designed ortho-BT probe demonstrates superior performance for nitrite detection, enabling rapid and semiquantitative on-site measurements.
• The precise modulation of benzothiazole binding sites represents a promising strategy for developing advanced fluorescent sensing materials.
• This work is expected to open new avenues in probe design methodology for analytical applications.