Flow cytometry characterization

Rychlik, L Cardova, L. Sevcik, M. Barrow, P. A. Flow cytometry characterization of Salmonella typhimurium mutants defective in proton translocating proteins and stationary-phase growth phenotype. J. Microbiol. Methods 2000, 42, 255-263. 

Several additional instrumental techniques have also been developed for bacterial characterization. Capillary electrophoresis of bacteria, which requires little sample preparation,42 is possible because most bacteria act as colloidal particles in suspension and can be separated by their electrical charge. Capillary electrophoresis provides information that may be useful for identification. Flow cytometry also can be used to identify and separate individual cells in a mixture.11,42 Infrared spectroscopy has been used to characterize bacteria caught on transparent filters.113 Fourier-transform infrared (FTIR) spectroscopy, with linear discriminant analysis and artificial neural networks, has been adapted for identifying foodbome bacteria25,113 and pathogenic bacteria in the blood.5... 

The synthesis and characterization of a somatostatin receptor-specific peptide H2N-(DPhe)-cyclo[Cys-Phe-(D-Trp)-Lys-Thr-Cys]-Thr-OH, labeled with an indo-dicarbo- and an indotricarbocyanine dye at the V-terminal amino group were described in [34], The ability of these fluorescent contrast agents to target the somatostatin receptor was demonstrated by flow cytometry in vitro, wherein the indotricarbocyanine conjugate led to elevated cell-associated fluorescence on somatostatin receptor-expressing tumor cells. The intracellular localization was visualized using NIR fluorescence microscopy. 

While more commonly used to count or otherwise characterize cells for medical applications, Coulter Counters and flow cytometry technique can also be applied to the analysis of pollen grains in allelopathic studies. They are quite useful in determining the size and number of pollen grains. The technique is often used for assessing the production and size of pollen from the originating individual rather than how much was transferred to heterospecific stigma, as would be needed in a basic assessment of potential allelopathic interactions. 

Krutzik, P.O., Hale, M.B., and Nolan, G.P., 2005. Characterization of the murine immunological signaling network with phosphospecific flow cytometry, J. Immunol., 175,2366, 2005. 

Radiative Transfer., 102, 62 (2006). Characterization of Spherical Particles using High-Order Neural Networks and Scanning Flow Cytometry. 

A series of silica nanoparticles doped with cyanine dye DY-635 (Dyomics) were also prepared, characterized, and investigated in flow cytometry and fluorescence imaging applications [77]. Also these dye-nanoparticles demonstrate high, stable, and tunable fluorescence intensity and are useful for multicolor detection. 

Keij J, Steinkamp J (1998) Flow cytometric characterization and classification of multiple dual-color fluorescent microspheres using fluorescence lifetime. Cytometry 33 318-323... 

In general, flow cytometry is an optical analytical method to characterize cells or particles in suspension. Accordingly, a flow cytometer is simply described as a specialized fluorescence microscope equipped with a quantitative high-throughput detector system to measure various cellular parameters [33-35],... 

In some instances, flow cytometry assays are a superior alternative to conventional procedures for the determination of equilibrium binding constants (Stein et al., 2001). In contrast to assays that employ radiolabelled ligands, which measure population mean values for binding constants, flow cytometry methods can measure those values in individual cells, revealing heterogeneity in receptor expression within a population of cells or membrane vesicles. Furthermore, small samples can be characterized in a short period of time (hours). This approach to receptor-binding analysis may be limited only by the availability of a properly characterized fluorescent ligand. 

Parod, R. J. and Brain, J. D. (1983) Uptake of latex particles by macrophages characterization using flow cytometry. Am. J. Physiol. 245, Cell Physiol. 14), C227-C234. 

H., Nakahata, T. (2005). Prospective characterization of neural stem cells by flow cytometry analysis using a combination of surface markers. J Neurosci Res. 80, 456-66. 

As indicated in Chapter 33, flow cytometry has developed rapidly to provide a powerful means of characterizing complex cell populations, both in terms of quantitative analysis of functional cell-associated molecules, and, as is considered here in more detail, the simultaneous analysis of combinations of markers that can be used to identify functional subpopulations of cells. Many of the considerations discussed in the previous chapter are relevant, but issues particularly pertinent to this type of analysis relate to the independence of the markers used, both at the level of the labeling process and at the level of cytometric analysis. 

Despite these problems, flow cytometry has had some noted success in aquatic research, particularly in relation to studies on the phytoplankton. Because all phytoplankton possess chlorophyll, but only the cyanobacteria possess the phycobiliproteins, autofluorescence signatures from water samples, based on the chlorophyll (fluorescence >630 nm), phycoerythrin (fluorescence <590 nm), and forward scatter of particles, have been used to characterize the changes that occur in plankton at different depths or at different locations (Figs. 11.5 and 11.6). 

The difficulties of characterizing the cell physiological properties can explain the difficulties in applying these models and why they have not been widely used in the solution of biochemical engineering problems. On the other hand, the advances in monitoring, especially in flow cytometry, and in computer science development, that increase the capacity for model... 

In flow cytometry, measurements are made as cells or particles suspended in a fluid pass through the apparatus in single file. This allows the characterization and measurement (multiparametric) of fimctional aspects of single cells or particles, and electrical or mechanical sorting of cells/particles into distinct populations. In order to understand the basis of flow cytometry it is important to consider the key components comprising a flow cytometer (see Figure 6.9). 

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