High-Performance Raman Spectroscopic System Based on a Single Spectrograph, CCD, Notch Filters, and a Kr+ Laser Ranging from the Near-IR to Near-UV Regions

Abstract

We describe the performance of a high-throughput system for detecting Raman spectra excited in the range from 320 to 750 nm. The system utilizes notch filters to reject Rayleigh scattering, a single polychromator as the dispersive element, and photon detection via a charge-coupled device. The filters, mirrors, and grating are changed to maximize performance in each excitation region. The excitation source consists of a Kr+ ion laser. Good-quality Raman data are reported for rhodamine 6G at 0.1 mM in methanol with the use of 752.5-nm excitation, and 0.2 mM flavin adenine dinucleotide (FAD) in tris buffer with the use of 647.1-nm excitation. High-quality resonance Raman data for 0.1 mM N-acetyl-glycine ethyl dithio ester in 5% CH3CN/H2O are also reported with the use of 324.0-nm excitation.