Flow cytometry is a biophysical tool that allows rapid counting and sorting of cells or particles in solution. Each particle passes through an electronic system capable of detecting the light scattered by each of them, which pass in line (one by one) through the laser light beam. The individual light signal scattered when interfering with the light source is picked up by detectors and processed through a computer program. Among the most important analytical characteristics of flow cytometers is its ability to measure multiple cellular parameters such as size, shape, complexity, autofluorescence, as well as to detect and identify cellular components by using fluorescent markers with a suitable configuration of the equipment. These qualitative and multiparametric measurements allow to define the properties of a cellular population or even subpopulations that compose it.
The analysis of samples in the Flow Cytometry Laboratory at IMO consists of the characterization of populations and subpopulations of autofluorescent organisms, such as, cyanobacteria and protists capable of photosynthesis as well non-fluorescent particles as viruses, bacteria and eukaryotic cells that can be stained and analysed from both natural environments and experimental approaches such as cell cultures, among others.
The Flow cytometry laboratory has capacities in equipment, infrastructure and experienced technical-professional personnel for analysis of samples from cultures, as well as from the environment from both fresh or saline matrices such as rivers, lagoons, and sea water. We count with a FACSCalibur flow cytometer equipped with a blue emission laser (λ = 488 nm), which allows to discriminate both natural and induced fluorescence (for bacterial analysis using DNA stains) using 5 detection channels, two for the optical parameters "Side Scatter" and "Forward Angle Light Scattering" and three detectors of fluorescence at specific wavelengths, 580, 610 and 670 nm. In addition, we have a high performance experimental cytometer, the InFlux® consisting of 5 excitation lasers (λ = 355-457-488-532-638 nm) and 16 detectors, giving a higher resolution in the results obtained. These detectors can be arranged according to the particular needs.
In conjunction with the analysis of each sample, a complete report is issued, containing the information of the equipment, number of samples received, general observations and a section of independent annexes identified as Fluorescence and Cells in which, the detected parameters are indicated with graphs (cytograms) and descriptive information of what was observed from each sample. The second part of the report provides the values of the requested parameters. The type of analysis is done according to the particular request.