Raman Dye Library for Multiplex Bioassay

A surface enhance Raman scattering (SERS) spectroscopy reference library was created for over ten Raman active dyes. Dye concentrations ranging from 1 mM to 1 pM were studied using a 785 nm wavelength Raman spectrometer, and the unique Raman spectra were recorded. Surface enhancement was achieved by adsorbing the dye molecules to 60 nm gold particles and the characteristics peaks were identified for each of the Raman active dyes. The dye library has aided with multiplex assay development. Multiplex assays are able to detect and distinguish between multiple analytes at the same time, such as multiple antibodies or antigens. To detect the capture of an analyte, it is necessary to have a unique dye that is specific to each analyte and to be able to distinguish the spectrum of each dye label in the multiplex spectrum. Three dyes were adsorbed individually to 60 nm gold nanoparticles and the dye modified gold nanoparticles were mixed to create a multiplex assay. Three multiplex experiments were run with a combination of three out of a possible six dyes: Nile Blue, IR-792, Malachite Green-ITC, Janus Green and Methylene Blue.