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Updated: Jun 10, 2026

Optical Trapping of Plasmonic Nanoparticles for In Situ Surface-Enhanced Raman Spectroscopy Characterizations
Published on: June 23, 2022
Confocal Raman microscopy of optical-trapped particles in liquids
Daniel P Cherney1, Joel M Harris
1Department of Chemistry, University of Utah, Salt Lake City, 84112, USA.
Abstract:
The in situ analysis of small, dispersed particles in liquids is a challenging problem, the successful solution to which influences diverse applications of colloidal particles in materials science, synthetic chemistry, and molecular biology. Optical trapping of small particles with a tightly focused laser beam can be combined with confocal Raman microscopy to provide molecular structure information about individual, femtogram-sized particles in liquid samples. In this review, we consider the basic principles of combining optical trapping and confocal Raman spectroscopy, then survey the applications that have been developed through the combination of these techniques and their use in the analysis of particles dispersed in liquids.
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