The first Raman-Activated Cell Sorter (RACS) model instrument, called RACS-1,
has been approved by the Ministry of Science and Technology of China (MoST)and
now in full operation in Qingdao, China.
This scientific instrument development
project “Application of Raman Tweezers in high-throughput live single-cell sorting”
was funded by the MoST Innovation in Methodology Program and was jointly
undertaken by QIBEBT and Beijing Wellsens Biotech Company (Wellsens).
RACS-1 consists of laser generator, Raman spectrometer, fluorescence
microscope, microfluidics devices and automatic control system. It is the first
scientific instrument that have achieved automatic or manual sorting based on
the Raman fingerprint of a single microbial cell. The key parameters of RACS-1
include: fast acquisition (1-100 ms) of Raman spectrum for a single microbial
cell, fast identification of cell species and status by Raman spectrum,
identification of uncultured bacteria by Raman-FISH; manipulation of
single-cells using Raman-Tweezers, single-cell counting based on Raman
spectrum, single-cell Raman spectra database, and Raman-activated Cell
Ejection, etc.
RACS differs from the Fluorescence-Activated Cell Sorter (FACS, i.e. flow
cytometry) in both scientific principles and core techniques. One key feature
of RACS is the capability of measuring the intrinsic properties of single-cells
without the need for labeling or biomarkers. Instead of depending on the
fluorescence of labeled molecules, RACS measures the intrinsic chemical profile
of a live cell in a non-invasive, label-free and in vivo manner, saving tedious
pretreatment and cell cultivation. It is sensitive to cellular genotypes,
phenotypes and physiological states. The combination of RACS with SERS (Surface
enhanced Raman scattering) can even detect single molecule inside cells. With
these core advantages, RACS is able to overcome three key bottlenecks in
biological research, namely, the phenotypic heterogeneity of cells, uncultured
microorganisms, detection of unknown cell phenotypes.
The successful development of the first RACS has enabled many novel
scientific and industrial applications that include screening and
characterization of oil-producing microalgae, isolation of
contaminant-degrading bacteria etc. Ongoing applications of RACS also include
mining of bio-resources from ocean, screening and development of bio-fuel and
bio-materials feedstock, bacterial detection in food industry, pharmaceutical
research, cancer cell detection and agricultural ecology.