Raman sorting and identification of single living micro-organisms with optical tweezers

Opt Lett. 2005 Jul 15;30(14):1800-2. doi: 10.1364/ol.30.001800.

Abstract

We report on a novel technique for sorting and identification of single biological cells and food-borne bacteria based on laser tweezers and Raman spectroscopy (LTRS). With this technique, biological cells of different physiological states in a sample chamber were identified by their Raman spectral signatures and then they were selectively manipulated into a clean collection chamber with optical tweezers through a microchannel. As an example, we sorted the live and dead yeast cells into the collection chamber and validated this with a standard staining technique. We also demonstrated that bacteria existing in spoiled foods could be discriminated from a variety of food particles based on their characteristic Raman spectra and then isolated with laser manipulation. This label-free LTRS sorting technique may find broad applications in microbiology and rapid examination of food-borne diseases.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / cytology*
  • Bacteria / isolation & purification*
  • Cell Separation / instrumentation*
  • Cell Separation / methods
  • Equipment Design
  • Equipment Failure Analysis
  • Lasers*
  • Micromanipulation / instrumentation*
  • Micromanipulation / methods
  • Microspheres
  • Physical Stimulation / methods
  • Specimen Handling / instrumentation*
  • Specimen Handling / methods
  • Spectrophotometry, Infrared / instrumentation
  • Spectrophotometry, Infrared / methods
  • Spectrum Analysis, Raman / instrumentation*
  • Spectrum Analysis, Raman / methods