High-throughput single-cell sorting by stimulated Raman-activated cell ejection.

Area of Science:

• Biophotonics
• Cellular Biology
• Analytical Chemistry

Background:

• Raman-activated cell sorting (RACS) offers nondestructive, label-free single-cell isolation but suffers from low throughput due to weak Raman signals.
• Coherent Raman scattering (CRS) with microfluidics enhances throughput but struggles with small cells (<3 μm) and tissue sections.

Purpose of the Study:

• To develop a high-throughput single-cell sorting technique that overcomes the limitations of existing Raman-based methods.
• To enable label-free sorting of diverse biological samples, including bacteria, fungi, and tissue sections.

Main Methods:

• Integration of stimulated Raman imaging, in situ image decomposition, and laser-induced cell ejection into a single platform (S-RACE).
• Utilized Raman signatures for guiding the ejection of live bacteria and fungi.
• Demonstrated sorting of lipid-rich *Rhodotorula glutinis* from a mixture at ~13 cells/second.
• Incorporated a closed-loop feedback circuit for real-time imaging, identification, and ejection.

Main Results:

• Achieved high-throughput single-cell sorting using stimulated Raman scattering (SRS).
• Successfully sorted specific cell types, like *Rhodotorula glutinis*, based on their Raman fingerprints.
• Verified sorting accuracy using quantitative polymerase chain reaction (qPCR).
• Demonstrated compatibility with both single cells and tissue sections.

Conclusions:

• S-RACE provides a powerful, high-throughput solution for label-free single-cell sorting.
• The technology is versatile, applicable to various cell types and tissue samples.
• Opens new avenues for applications in cell analysis, diagnostics, and research.