SERS Microscopy (µSERS) Selective and Sensitive Localization of Proteins in Tissue Specimens C. Jehn, B. Küstner, F. Schöppler, F. Baum, M. Schütz, M. Gellner and S. Schlücker Institute of Physical Chemistry University of Würzburg Germany http://www.phys-chemie.uni-wuerzburg.de SERS Round Table Discussion, Poltersdorf, October 3-5, 2007

Outline Immunohistochemistry: Basics Biofunctionalized Nanoparticles SERS Microscopy: Proof of Principle Novel SERS labels SERS Imaging of PSA in Prostate Biopsies Outlook Label 1

Immunohistochemistry Protein Target Protein/Antigen Tissue Section Tissue Section Label + 1. Label 2. Remove Unbound Antibodies 2

Immunohistochemistry (IHC): Quo Vadis ? Multiplexing Capacity of Different Labelling Approaches ca. 1-3 ca. 1-3 ca. 3-10 ca. 10-100 Dyes Fluorophores Quantum Dots SERS Labels Absorption Fluorescence Emission Raman Scattering small Raman line width minimal spectral overlap 3

Functionalized Nanoparticles for Nanodiagnostics Spacer Immuno-SERS Label + Spacer + + Gold Nanoparticle Antibody Raman Label 4

Self-Assembled Monolayer (SAM) on Gold Nanoparticles Spacer 5

Hollow Gold Nanoparticles: Synthesis Solid Ag spheres Hollow Au shells Ag colloid max ~ 400 nm Au-Ag alloy max 550 – 900 nm 3 Ag + Au 3+ 3 Ag + + Au Nanoparticles with tunable surface plasmon resonance ! 6

Hollow Gold Nanoparticles: Characterization 50 nm Plasmon resonance energy depends on shell thickness 7

Spectrum of Immuno-SERS lable Wavenumber / cm-1 Raman Intensity 1750 1500 1000 750 1250 Selected Raman bands: SERS distance dependence SERS selection rules Electronic resonance D. S. Grubisha, R. J. Lipert, H.-Y. Park, J. Driskell, M. D. Porter, Anal. Chem. 2003, 75, 5936. Schlücker, Küstner, Punge, Bonfig, Marx, Ströbel, J. Raman Spectrosc. (rapid comm.) 2006, 37, 719-721. 8

S(-) L(-) E(+) SERS Microscopy (µSERS): Proof of Principle B A D E C Localization of PSA in Prostate Biopsies A B C E D S(-) L(-) E(+) A - C: Epithel PSA (+) D: Stroma PSA (–) E: Lumen PSA (–) Schlücker, Küstner, Punge, Bonfig, Marx, Ströbel, J. Raman Spectrosc. (rapid comm.) 2006, 37, 719-721. 9

Outline Immunohistochemistry: Basics Biofunctionalized Nanoparticles SERS Microscopy: Proof of Principle Novel SERS labels SERS Imaging of PSA in Prostate Biopsies Outlook Label 1 11

Bioconjugation: Sterical hindrance by SAM Route 1 Route 2 Dual SAM Silica encapsulated Novel SERS labels Sterical hindrance 10

Route 1: Novel SERS labels Au Au shorter spacer unit Au longer spacer unit 11

Route 1: Novel SERS labels Absorption 12

Silica encapsulated nanoparticles Route 2: Novel SERS labels gold nanoparticle spacer Self Assembled Monolayer silica encapsulation Au Sub Monolayer vs. P. Mulvaney, M. D. Musick, C. D. Keating, M. J. Natan, Langmuir 2003, 19, 4784. 13

Route 2: Novel SERS labels 50 nm silica encapsulation 100 nm 100 nm 50 nm 14

Route 2: Novel SERS labels Absorption SERS 15

Raman Microspectroscopic Imaging y Spatial Coordinates Wavenumber x Point Mapping Line Mapping L Spectrometer Global Imaging Spectrometer LCTF S. Schlücker, M. D. Schaeberle, S. W. Huffman, I. W. Levin, Anal. Chem. 2003, 75, 4312-4318. 16

SERS Imaging of PSA in Prostate Biopsies SERS Image Brightfield Image Intensity @ 1340 cm-1 20 µm 17

SERS Imaging of PSA in Prostate Biopsies Intensity @ 1340 cm-1 18

Outlook: Multiplexing µSERS vs. Fluorescence: Multiplexing capability Only single laser excitation No photobleaching Quantitation 1 1 2 2 3 3 4 4 19

Acknowledgement Pathology (Mannheim/Heidelberg) P. Ströbel A. Marx Organic Chemistry (Würzburg) C. Schmuck, M. Bauer, P. Wich