Cell Surface Protein Detection using Surface-Enhanced Raman Scattering (SERS) Gold Nanoparticles

Surface enhanced Raman scattering (SERS) Au nanoparticles have been used as novel cell surface receptor labels for the identification of markers of interest in chronic lymphocytic leukemia (CLL) and lung cancer. Biocompatibility of the particles was improved using multiple coating and particle protection strategies. Each of these strategies facilitated different methods for the inclusion of Raman active reporter molecules, as well as for different types of targeting moieties. Characterization of the SERS nanoparticles was undertaken including quantification of the number of antibodies bound to the surface. Long-term stability of both the nanoparticle Raman signal intensity and monodispersity was assessed under standard storage conditions, as well as conditions suitable for in vitro biological experiment. The SERS labeling platform has been demonstrated as being compatible with traditional pathology protocols including flow cytometry, and stains such as giemsa. SERS detection using these particles has been adapted to models for both adherent and circulating malignancies, in addition to patient cell samples in the example of CLL. The narrow vibrational spectra of SERS particles used in this study greatly increase the multiplexed labeling potential over traditional fluorescence-based technologies. Preliminary multiplexed labeling of CLL has also been demonstrated.