Method for activation of aqueous dispersions of silver nanoparticles for purposes of surface enhanced Raman spectroscopy

摘要

The present invention relates to a method for activation of aqueous dispersions of silver nanoparticles for purposes of surface enhanced Raman spectroscopy, wherein a solution of chloride ions is added to the aqueous dispersion of silver nanoparticles in a concentration within the range of 1 mol.dme-3 to the concentration of a saturated solution in such an amount that the final chloride ion concentration in the activated dispersion ranges from 0.4 mol.dme-3 to 1 mol.dme-3. Preferably, oxygen is added to the dispersion in the course of activation. This method leads to recrystallization of silver particles, which is faster and more reproducible for the purposes of surface enhanced Raman spectroscopy than the particle aggregation so far known in the art.