Lipid-encapsulation of surface enhanced Raman scattering (SERS) nanoparticles and targeting to chronic lymphocytic leukemia (CLL) cells

60 nm diameter gold nanoparticles (AuNP) were coated with a ternary mixture of lipids and targeted to human lymphocytes. Previously, the versatility, stability and ease of application of the lipid coating was demonstrated by the incorporation of three classes of Raman-active species. In the present study, lipid encapsulated AuNPs were conjugated to two targeting species, namely whole antibodies and antibody fragments (Fab), by two methods. Furthermore, in vitro targeting of lipid-encapsulated Au nanoparticles to patient-derived chronic lymphocytic leukemia (CLL) cells was demonstrated by Raman spectroscopy, Raman mapping, and darkfield microscopy. These results further demonstrate the versatility of the lipid layer for imparting stability, SERS activity, and targeting capability, which make these particles promising candidates for biodiagnostics.