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Optical tweezers: a non-destructive tool for soft and biomaterial investigations

  • Life, New Materials and Plasmonics
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Abstract

Optical tweezers are a key technique for trapping and contactless manipulation of particles at the micro- and nanoscale that can exert and sense forces from hundreds of piconewton down to few femtonewton. In their simplest implementation, they are based on a single laser beam tightly focused to a high-intensity diffraction-limited spot. Here, after reviewing the general theoretical background on optical forces, we focus on their calibration and show a comparison between frequency and time domain methods. Then, we show novel measurements and calculations of optical forces on gold nanoparticles discussing their size scaling behavior. Finally, we describe recent applications of chiral optical trapping to soft materials, and integration of optical tweezers with Raman spectroscopy for ultra-sensitive spectroscopy of biomolecules in liquids.

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Acknowledgments

We acknowledge support from “Programma Operativo Nazionale Ricerca e Competitivitá” 2007–2013, Project PON01_01322 PANREX, Project PAC02L3_00087 SOCIAL-NANO, and the MPNS COST Action 1205 “Advances in Optofluidics: Integration of Optical Control and Photonics with Microfluidics”.

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Author notes

  1. R. Sayed

    Present address: National Institute for Standards, P. O. Box: 136 Giza, Giza, 12211, Egypt

Authors and Affiliations

  1. CNR-IPCF, Istituto Processi Chimico-Fisici, V.le F. Stagno D’Alcontres 37, 98158, Messina, Italy

    A. Magazzú, D. Spadaro, M. G. Donato, R. Sayed, E. Messina, C. D’Andrea, A. Foti, B. Fazio, M. A. Iatí, A. Irrera, P. G. Gucciardi & O. M. Maragó

  2. Dipartimento di Fisica e Scienze della Terra, Universitá di Messina, V.le F. Stagno D’Alcontres 31, 98166, Messina, Italy

    A. Magazzú, A. Foti & R. Saija

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  1. A. Magazzú
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Correspondence to O. M. Maragó.

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This contribution is the written, peer-reviewed version of a paper presented at one of the two conferences “From Life to Life: Through New Materials and Plasmonics”—Accademia Nazionale dei Lincei in Rome on June 23, 2014, and “NanoPlasm 2014: New Frontiers in Plasmonics and NanoOptics”—Cetraro (CS) on June 16–20, 2014.

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Magazzú, A., Spadaro, D., Donato, M.G. et al. Optical tweezers: a non-destructive tool for soft and biomaterial investigations. Rend. Fis. Acc. Lincei 26 (Suppl 2), 203–218 (2015). https://doi.org/10.1007/s12210-015-0395-4

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