Though the application of particles and cell counting technology is diverse, there is a common need for particulate standards. We manufacture count standards for both dedicated particle counters and flow cytometers. Enumeration of cells in a sample may be achieved through use of a microsphere count standard. Cell count may be calculated by determining the ratio of fluorescent count beads to unlabeled cells. For information on proper mixing and sampling, see TSD 0706: Handling & Pipetting Concentration Standards.

Flow Cytometry Absolute Count Standard™

Our Flow Cytometry Absolute Count Standard™ is a precisely counted population of microspheres for estimating counts of unlabeled cells via flow cytometry. The microspheres are ~7-9µm in diameter and supplied at ~1e+6 beads/mL. Beads are internally labeled with multiple fluorophores for excitation with common lasers (e.g. 488nm, 633nm) and discrimination from the cell population. By evaluating the ratio of microspheres to cells, the volumetric number of cells may be determined.
Catalog Number Nominal Mean Diameter (µm) Product Data Sheet Safety Data Sheet
580 Flow Cytometry Absolute Count Standard™ PDS 880.pdf SDS ST334.pdf


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