A highly selective fluorescent probe for pyrophosphate detection in aqueous solutions

Area of Science:

• Analytical Chemistry
• Materials Science
• Inorganic Chemistry

Background:

• Pyrophosphate (PPi) is a crucial analyte in biological and environmental systems.
• Sensitive and selective detection methods for PPi are essential for various applications.
• Existing methods may lack selectivity or require complex procedures.

Purpose of the Study:

• To develop a novel and simple fluorescence enhancement method for selective pyrophosphate (PPi) sensing.
• To investigate the complex formation between tris(8-hydroxyquinoline-5-sulphonate) thulium(III) [Tm(QS)(3)] and PPi.
• To establish the analytical performance of the developed sensing system.

Main Methods:

• Utilized a 1:1 metal complex formation between Tm(QS)(3) and PPi ions in aqueous solution.
• Employed fluorescence spectroscopy to monitor the enhancement upon complexation.
• Evaluated selectivity against various common anions.

Main Results:

• Achieved selective fluorescence enhancement for PPi detection.
• Established a linear response range from 1.6 × 10⁻⁷ to 1.0 × 10⁻⁵ mol/L for PPi.
• Determined a low detection limit of 2.3 × 10⁻⁸ mol/L and an association constant of 2.6 × 10⁵ mol/L for the Tm(QS)(3)-PPi complex.
• Demonstrated high selectivity over other tested anions due to the stability of the inorganic complex.

Conclusions:

• The Tm(QS)(3) complex provides a selective and sensitive platform for fluorescence-based pyrophosphate sensing.
• The method's simplicity and effectiveness make it suitable for aqueous PPi analysis.
• The observed selectivity is attributed to the robust inorganic complex formed between pyrophosphate and Tm(QS)(3).