Raman-tweezers in microfluidic system for analysis and sorting of living cells.

We built an experimental apparatus for Raman analysis and sorting of optically trapped living cells (microorganisms, cell cultures) in microfluidic environment. Optical trapping allowed non-contact spatial confinement and separation of the analyzed cells, while Raman spectroscopy was used for determination of the chemical parameters of the cells. Special microfluidic chip serves to deliver the cells to the area of Raman-tweezers and to separate and isolate the selected cells. The system allows fully automatic analysis and sorting of living microorganisms according to selected parameters of the Raman spectrum. The selected cells can be easily removed from the microfluidic chip in a form of cell-containing agarose plug. This system may find its use in various biological, biotechnological and medical disciplines. The research was supported by Ministry of Education, Youth and Sports CR (MEYS) (projects LO1212 and LD14069) and the research infrastructure by MEYS and EC (projects LO1212 and CZ.1.05/2.1.00/ 01.0017) and by Academy of Sciences of the Czech Republic (project RVO:68081731).