[Restraining pyridine from laser carbonization by SnCl2 in the SERS measurements]

Laser carbonization is an inherent problem frequently encountered in the measurements of surface-enhanced Raman scattering (SERS), especially for the reactive molecules. Pyridine (Py) is one of such examples though it is a common molecule as probe in the SERS studies. The introduction of SnCl2, which has few Raman peaks at low frequency, effectively restrains the pyridine from carbonization. The findings here provide a new convenient chemical way to improve the routine SERS analysis of reactive organic/bio-molecules instead of physical ones reported in the literature like vacuum, inert atmosphere, low temperature, low laser power, and so on. It is expected that this method is also applicable in the SERS study of other vulnerable organic/bio-molecules.