Immuno-Surface-Enhanced Coherent Anti-Stokes Raman Scattering Microscopy: Immunohistochemistry with Target-Specific Metallic Nanoprobes and Nonlinear Raman Microscopy

Immunohistochemistry (IHC) is one of the most widely used staining techniques for diagnostic purposes. The selective localization of target proteins in tissue specimens by conventional IHC is achieved with dye-labeled antibodies in combination with light microscopy. In this contribution, we demonstrate the proof-of-principle for IHC based on surface-enhanced coherent Raman scattering for contrast generation. Specifically, antibody-labeled metallic nanoshells in conjunction with surface-enhanced coherent anti-Stokes Raman scattering (SECARS) microscopy are employed for the selective, sensitive and rapid localization of the tumor suppressor p63 in the benign prostate. To disentangle the role of electronic and molecular resonances in this plasmon-assisted four-wave mixing process involving metal colloids, their relative contributions were measured in a two-channel microfluidic chip specifically designed for direct comparison purposes.