(393a) Enantioselective Properties of Chiral Surface Modified Gold Nanoparticles and Their Variation with Temperature, Wavelength, and Particle Size

Surfaces of chemically synthesized gold nanoparticles were modified with both L and D enantiomers of glutathione and cysteine to make them chiral.  The chirality of these nanoparticles was examined by using various chiral probe molecules such as  2-Butanol, glucose, tartaric acid and alanine. We have used simple polarimetery to test the chirality at  25 degrees celsius and 436 nm wavelength.  Our work shows that L-cysteine is better ligand for adsorbtion of the probe molecules than L-glutathione. L-cysteine coated Au nanoparticles show larger enantioselective separation in comparison to L-glutathione coated Au nanoparticles.  In addition, glucose has highest enantioselective separation in comparison to 2-butanol, tartaric acid, and alanine.  Thus we see that this method for separating chiral molecules on the surface of chirally modified gold nanopartices works with different efficacy for a range of proble molecules.  Furthermore, these effects are altered depending on which ligand was used to modfy the gold nanoparticle surface.