Rapid and high-precision quantitative analysis based on substrate rotation-enhanced Raman scattering effect

In this paper, we proposed a substrate rotation-enhanced Raman scattering (SRERS) effect. The substrate, prepared by the technology of texturization and electroplating, is fixed on the motor and rotates with it while collecting Raman signal. The relative standard deviation (RSD) of Raman intensity in multiple measurements is less than 9.1%, which indicates that the Raman signal is stable and reproducible based on the SRERS effect. What is more, this method eliminates the fluctuation of the local electric field intensity caused by the inhomogeneity of the substrate and makes the "equivalent hot spots" distributed uniformly on the whole surface. The quantitative analysis with the Rhodamine 6G (R6G) and the lipid-soluble drug Oxaprozin (OXA) as the probe respectively has demonstrated that the Raman intensity of R6G at 612 cm(-1)with respect to concentration tend to linear ranging from 10(-10)to 10(-8)mol/L with the correlation coefficient (R-2) is more than 0.96, and the Raman intensity of OXA at 1,003 cm(-1)with respect to concentration tend to linear ranging from 3.4 * 10(-6)to 3.4 * 10(-4)mol/L (prepared with 50%v/v ethanol) with the correlation coefficient (R-2) is more than 0.97. The mechanism of SRERS is given, and the theory analysis indicates that the Raman signal obtained is the mean of a large number of laser-scanning points' contributions.