Code: ThOH	Time Slot/Poster Number: 2:00 - 2:30 pm	Session: Tip-Enhanced and Near-Field Raman II
Tip-Enhanced Raman Scattering Sensitive, Label-Free, Nanoscale
Volker Deckert1, 2
1Friedrich Schiller University Jena, Jena, Germany; 2IPHT - Institute of Photonic Technology, Jena, Germany
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Summary
Life science applications of tip-enhanced Raman scattering (TERS) are discussed. This includes for example simple identification of bio-molecules like amino acids, short peptides, and RNA and their specific properties with respect to the optical near field. Other, more complex TERS experiments will be discussed with respect to specific structural properties of distinct cell compartments.

Code: ThOH	Time Slot/Poster Number: 2:30 - 3:00 pm	Session: Tip-Enhanced and Near-Field Raman II
Higher-Order Optical Modes and Nanostructures for Detection and Imaging Applications
Zachary Schultz1; Ira Levin2
1Notre Dame, Notre Dame, IN; 2National Institutes of Health, Bethesda, MD
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Summary
Tip-enhanced Raman results obtained in our lab indicate that the use of higher-order, Hermite-Gaussian, optical modes provide beneficial interactions for TERS imaging in a back-scattering geometry. The higher-order, radially polarized, mode induces an electron oscillation normal to the sample surface resulting in enhanced Raman scattering from beneath the AFM tip in a back-scattering detection configuration. This imaging methodology has been effective at detecting nanoscale features in both materials and biological applications. Results indicate the combination of these higher order modes and metallic nanostructures offers an effective means to high- sensitivity, label-free, Raman spectroscopic imaging.

Code: ThOH	Time Slot/Poster Number: 3:00 - 3:30 pm	Session: Tip-Enhanced and Near-Field Raman II
Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy
Markus B. Raschke
University of Washington, Seattle, WA
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Summary
The symmetry selectivity of phonon Raman spectroscopy of crystalline solids allows for the determination of nano-crystallographic information in tip-enhanced Raman scattering (TERS). The selection rules and necessary degrees of freedom arise from the combination of the Raman selection rules reflecting crystal symmetry superimposed by the polarization and k-vector-dependent field enhancement and scattering of the scanning probe tip. We demonstrate the identification of intrinsic ferroelectric domains of individual BaTiO3 nanocrystals through selective probing of different transverse optical phonon modes. The technique is generally applicable and structural inhomogeneities, phase transitions, ferroic order occurring on nanometre length scales can be studied.

Code: ThOH	Time Slot/Poster Number: 3:30 - 3:50 pm	Session: Tip-Enhanced and Near-Field Raman II
Synthesis And Nanosoldering Of Nanowires For Tip-Enhanced Raman Spectroscopy
Pierre Brodard; Mikhael Bechelany; Laetitia Philippe; Johann Michler
EMPA, Swiss Federal Laboratories for Materials Tes, Thun, Switzerland
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Summary
Surface enhanced Raman spectroscopy is based on the absorption of light by nanometer-sized metal particles, resulting in large enhancement of the Raman signal. By replacing the metal particles by a metallic nanotip, the enhancement can be localized. The resulting tip-enhanced Raman spectroscopy (TERS) is capable of measuring Raman spectra with high spatial resolution, effectively overcoming the diffraction limit. We show that hemispherical gold droplets on top of silicon nanowires grown by the vapor-liquid-solid (VLS) method as well as silver nanowires synthesized by electrochemical deposition and attached to atomic force microscope cantilevers improve the feasibility and reproducibility of the TERS technique.

Code: ThOH	Time Slot/Poster Number: 3:50 - 4:10 pm	Session: Tip-Enhanced and Near-Field Raman II
Imaging And Characterization Of Caveolae With TERS During Stimulated Wound Healing
Tanja Deckert-Gaudig1; Melissa Mariani2; Volker Deckert1
1IPHT - Institute of Photonic Technology, Jena, Germany; 2Mount Sinai School of Medicine, New York City, New York
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Summary
Lipid distribution and aggregation on a cell membrane play a major role in a process like wound healing. An important subset of lipid components are caveolae, invaginations on the cell membrane facilitating activities such as cell movement and cell polarization. With tip-enhanced Raman scattering (TERS) it is possible to localize and characterize these species on the cell membrane of epidermal keratinocytes during stimulated would healing without destruction of the cell. According to the spectra the main components of caveolae are sphingomyelins and the protein caveolin.