Article

Near-field Raman spectroscopy of biological nanomaterials by in situ laser-induced synthesis of tip-enhanced Raman spectroscopy tips.

School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
Optics Letters (Impact Factor: 3.39). 06/2012; 37(12):2256-8. DOI: 10.1364/OL.37.002256
Source: PubMed

ABSTRACT We report a new approach in tip-enhanced Raman spectroscopy (TERS) in which TERS-active tips with enhancement factors of ∼10(-5)× can be rapidly (1-3 min) produced in situ by laser-induced synthesis of silver nanoparticles at the tip apex. The technique minimizes the risks of tip contamination and damage during handling and provides in situ feedback control, which allows the prediction of the tip performance. We show that TERS tips produced by this technique enable the measurement of spatially resolved TERS spectra of self-assembled peptide nanotubes with a spatial resolution of ∼20  nm.

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