Table 6.6 Fluorescein equivalents in Molecular Probes yellow-green–fluorescent FluoSpheres beads.

Microsphere Diameter (µm)
Fluorescein Equivalents per Microsphere *
0.021.8 × 102
0.043.5 × 102
0.17.4 × 103
0.21.1 × 105
0.52.0 × 106
1.01.3 × 107
2.03.1 × 107
101.1 × 1010
153.7 × 1010
* Values may vary slightly between batches of these products. These data were obtained by taking known numbers of beads and totally dissolving the polystyrene to release the dye. The fluorescence of the released dye was then compared to a fluorescein standard curve. The relationship of fluorescence (fluorescein equivalents) to bead size scales as the cube of the bead radius, as it should for a spherical bead where the dye fills the full volume (as opposed to only being on the surface).

For Research Use Only. Not for use in diagnostic procedures.