A Fluorescent and Colorimetric Chemosensor Detecting Pd²⁺ Based on Chalcone Structure with Triphenylamine

Area of Science:

• Chemical sensing
• Materials science
• Analytical chemistry

Background:

• Chalcone derivatives are versatile scaffolds for developing chemosensors.
• Triphenylamine groups can impart desirable photophysical properties to organic molecules.
• Selective detection of palladium ions (Pd2+) is crucial in environmental and biological monitoring.

Purpose of the Study:

• To synthesize and characterize a new chalcone-based chemosensor, DiPP.
• To investigate the utility of DiPP for the selective detection of Pd2+.
• To evaluate the sensing performance of DiPP using both fluorometric and colorimetric methods.

Main Methods:

• Synthesis of DiPP ((E)-3-(4-(diphenylamino)phenyl)-1-(pyridin-2-yl)prop-2-en-1-one).
• Fluorometric and colorimetric analyses for Pd2+ detection.
• Binding studies using Job plot, NMR titration, and ESI-mass spectrometry.
• Density Functional Theory (DFT) calculations for mechanistic insights.

Main Results:

• DiPP demonstrated a fluorescence turn-off response and a distinct color change (yellow to purple) upon binding with Pd2+.
• The sensor exhibited a 1:1 binding ratio with Pd2+.
• Low detection limits for Pd2+ were achieved (0.67 µM fluorometric, 0.80 µM colorimetric).
• DiPP-based test strips showed excellent selectivity for Pd2+ over other metal ions.

Conclusions:

• DiPP is a highly effective chemosensor for the sensitive and selective detection of Pd2+.
• The combination of fluorometric and colorimetric detection offers a robust analytical approach.
• The developed sensor holds potential for practical applications in Pd2+ monitoring.