Raman sorting and identification of single living micro-organisms with optical tweezers.
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.
Xie
Changan
C
Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353, USA. xieca@yahoo.com
Chen
De
D
Li
Yong-Qing
YQ
D001419:Bacteria / Q000166:cytology* / Q000302:isolation & purification*; D002469:Cell Separation / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D008863:Microspheres; D010812:Physical Stimulation / Q000379:methods; D013048:Specimen Handling / Q000295:instrumentation* / Q000379:methods; D013055:Spectrophotometry, Infrared / Q000295:instrumentation / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000295:instrumentation* / Q000379:methods