Synthesis and Characterization of Antioxidant Biphenyl Appended 1,2,3‐Triazoles as Potential Chemo‐Sensor for Sn 2+ Ions: Excellent Selectivity and Low Detection Limit

Designing of chemo‐sensors is a new scope of intrigue among researchers. After inspecting the beneficial and harmful effects of Sn(II) metal ions in living species, 1,2,3‐ Triazole based chemo‐sensor 4 a have been synthesized via click route. In the current article, literarily new 1,2,3‐Triazoles ( 4 a – 4 d ) have been synthesized and identified via various spectroscopic means such as NMR( 1 H & 13 C), IR and mass spectrometry. Triazole 4 a was explored for recognition properties via absorption and emission spectroscopy and found specific and selective for Sn(II) metal ions. The recognition of Sn 2+ metal ions by probe 4a was not interfered because of other tested metal cations. The probe has very low detection limit of 0.47×10 −7 M and 3.8×10 −9 M via ultraviolet and fluorescence spectroscopy respectively which is lower than many previously reported sensors. The B−H plot and stern volmer's plot confirmed a high binding affinity between probe 4a and tin (II) metal ion. The association constant (K a ) and stern volmer constant (K sv ) were calculated as 13.36×10 5  M −1 and 12.6×10 6  M −1 from B−H plot and stern volmer's plot respectively. The Stoichiometric ratio between chemo‐sensor 4 a and Sn 2+ metal ions was confirmed as 1 : 1 by the job's plot. Moreover, in this study, the synthesized compounds 4 ( a – d ) were examined for their antioxidant properties. The total antioxidant activity (TAA) results indicate that the synthesized triazoles 4 ( a – d ) found to be excellent postulant for radical scavenging. TAA values for 4 a , 4 b , 4 c and 4 d are found to be 4.65±0.2, 6.79±0.3, 6.29±0.2, 5.06±0.1 (mM)(eq. ascorbic acid) per 100 mM of particle respectively.