Bis-triazole linked organosilane based sensing platform for Cu2+ ions and insilico tyrosinase inhibitor activity

Abstract

The development of a ligand for their selective and sensitive detection is required due to the widespread use of Cu²⁺ in many industrial processes and the potential threat to human health. Herein, we report a bis-triazole linked organosilane (5) derived from the Cu(I) catalyzed azide-alkyne cycloaddition reaction. The synthesized compound 5 was characterized by (¹H and ¹³C) NMR spectroscopic and mass spectrometry techniques. The UV-Visible and Fluorescence experiments of the designed compound 5 were performed with various metal ions, revealing its high selectivity and sensitivity to Cu²⁺ ions in MeOH: H₂O (8:2, v/v, pH = 7.0, PBS buffer) solution. The selective fluorescence quenching upon addition of Cu²⁺ to the compound 5 is due to Photo-induced electron transfer process (PET). The limit of detection of compound 5 to Cu²⁺ was calculated as 2.56 × 10^-6 M and 4.36 × 10^-7 M through UV-Visible and Fluorescence titration data, respectively. The possible mechanism of 1:1 binding of 5 with Cu²⁺ could be affirmed by the density functional theory (DFT). Further, it was found that compound 5 showed a reversible behavior towards Cu²⁺ ions by the accumulation of sodium salt of CH₃COO^- which can be used in the construction of molecular logic gate where Cu²⁺ and CH₃COO^- are considered as inputs and the absorbance at 260 nm as output. Moreover, the molecular docking studies provide useful information about compound 5's interaction with the tyrosinase enzyme (PDB ID- 2Y9X).

Keywords: Bis-triazole; Cu(2+); Fluorescence; Molecular docking; Organosilane.