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Updated: Jun 25, 2026

Quantifying the Binding Interactions Between Cu(II) and Peptide Residues in the Presence and Absence of Chromophores
Published on: April 5, 2022
A colorimetric sensor for Cu2+ in aqueous solution based on metal ion-induced deprotonation:
Junhai Huang1, Yufang Xu, Xuhong Qian
1Shang Hai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China.
Abstract:
A Cu2+-specific colorimetric sensor of a 1,8-naphthalimide chromophore integrated with a 2-aminodiphenylamine (2-adpa)-based receptor was designed and synthesized. Sensor had high selectivity and sensitivity for Cu2+ in neutral aqueous buffer solution. The analytical detection limit (ADL) was 3.0 x 10(-7) M. Based on the Cu2+-induced deprotonation of the diarylamino "NH" moiety, the coordination mode was proposed with 1:1 stoichiometry between and Cu2+. These results opened up possibilities for the construction of novel colorimetric sensors with a red-shift absorption in a D-pi-A system.
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