Flow cytometry describes the analysis of light diffraction and fluorescent properties of a population of cells or particles as they pass through one or more lasers. It is a powerful technique as it provides real quantitative information on a cell by cell or particle by particle basis. Flow cytometry can be used to determine a number of cell based parameters including size and granularity (internal complexity) of the cell, the cell surface expression of particular proteins using antibodies & fluorescent reporters, intracellular protein levels like chemokines, DNA content & cell cycle analysis, cellular uptake of particular fluorescent agents including CLIO-based particles & cell proliferation using cytoplasmic dyes.