Observation of SERS effect in Raman optical activity, a new tool for chiral vibrational spectroscopy

A new tool for chiral vibrational spectroscopy is here reported. A Surface Enhanced effect was observed using Raman Optical Activity (ROA). This observation opens new possibilities for ROA as a tool for vibrational spectroscopy. The combination of surface enhanced effect SE and ROA into SEROA, takes this tool to another level, where a single molecule may be studied with respect to chirality, secondary structure and fold determination. ROA has been able to provide information about important dynamics in molecular understanding. However, until recently ROA measurements have required a longer exposure and higher concentration of the sample. With SEROA, these obstacles can be overcome, in that both studies on single molecule, i.e., very low concentration, and faster acquisition of the signal can be achieved. In the present work silver colloids were mixed with solution, in which a pentapeptide, Met-Enkephalin, was dissolved. SEROA signals were recorded and the results are reported here.