Spectral Analysis of Multiplex Raman Probe Signatures

Abstract
Raman nanoparticle probes are an emerging new class of optical labels for interrogation of physiological and pathological processes in bioassays, cells, and tissues. Although their unique emission signatures are ideal for multiplexing, the full potential of these probes has not been realized because conventional analysis methods are inadequate. We report a novel spectral fitting method that exploits the entire spectral signature to quantitatively extract individual probe signals from multiplex spectra. We evaluate the method in a series of multiplex assays using unconjugated and antibody-conjugated composite organic−inorganic nanoparticles (COINs). Results show sensitive multiplex detection of small signals (in vivo and ex vivo multiplex analysis.