Defining the Structural Parameters of Triazole Ligands in the Templated Synthesis of Silver Nanoparticles

Abstract

This manuscript describes a one-pot method for the synthesis of size-and shape-selected silver nanoparticles (AgNPs) using Tollens' reagent [Ag(NH 3 ) 2 OH] as the silver source. Sugar triazole ligands facilitate the formation of monodisperse AgNPs in which the size and shape can be controlled according to the reaction conditions. Increasing the size of the ligand reduces size tunability but enhances colloidal stability in high-salt buffers. A key conclusion from this study is

Synthesis of the copper chelator TGTA and evaluation of its ability to protect biomolecules from copper induced degradation during copper catalyzed azide–alkyne bioconjugation reactions

“…13 Therefore, we believe that there is still room for further improvement and optimization of the ligand structures. We envisioned that TGTA would be a good alternative to the previously reported ligands, for a number of reasons: (1) the monosaccharide pendant groups increase the water solubility of the ligand and ( 2) reducing sugars, such as the galactosyl moiety, have previously been shown to be able to reduce metal species as exemplified by the reduction of Ag(I) to (Ag) by similar compounds in the work of Burley et al 15 and the reduction of Cu(II) to Cu(I) by D-glucose in the work of Misra and Biswas et al 16 Based on the literature observations, TGTA should be close to an optimal compound for CuAAC bioconjugation reactions in aqueous solutions as it contains the copper chelating/stabilizing properties of TBTA (identical core), increased water solubility due to the monosaccharide pendant groups and three equivalents of the reducing ability of a reducing sugar (D-galactose) which in the best case scenario would eliminate the need for utilizing other reducing agents such as sodium ascorbate. The synthesis of TGTA commenced through the use of standard synthetic protocols and is summarized in Scheme 1.…”