Supramolecular chirality of cysteine modified silver nanoparticles

Silver nanoparticles (∼45 nm) were prepared by citrate reduction of AgNO3 and modified with cysteine and N-, C- and S-protected cysteine derivatives. Based on interpretation of absorption and circular dichroism spectra in UV–Vis range, unusual chiral architecture of modified silver nanoparticles (independently on the cysteine enantiomer used) was uncovered. This phenomenon was observed even after modification of silver nanoparticles with racemate of cysteine. Influence of pH and reducing agent was studied.