Bio-Rad Bio-Plex Software® Upgrades and Conversions - Manual (Page 241)

Microsphere Handling
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Microsphere Handling
Microsphere Dispersion
xMAP microspheres will settle and aggregate if left undisturbed. You should
always ensure that they are evenly distributed before dispensing. Gentle
vortexing is the most effective method of mixing for most coated microsphere
preparations; however, sonication can also be used to separate aggregated
microspheres prior to coupling. After sonication, microspheres generally
remain dispersed for about 1 hour. Sonication is most effective if applied to a
centrifuged pellet of microspheres. In order to maintain bead concentration,
we suggest you centrifuge your stock beads before sonication.
The following two indirect sonication methods are effective at separating
aggregates in closed containers of microsphere preparations. Inserting a
sonicator probe into preparations is not recommended.
Probe Sonicator
To disperse a microsphere pellet using a probe sonicator:
1. Place probe tip in a small bath of water.
2. Insert the end of the microsphere tube near the tip of the sonicator
probe, without touching it. Do not immerse the tube closure.
3. Adjust sonication for optimal disruption and pulse sonicate until the
microsphere pellet is dispersed.
Bath Sonicator
To disperse a microsphere pellet using a bath sonicator:
1. Turn on the bath sonicator and examine the surface for an area of
maximum disruption.
2. Insert the end of the tube into the sonicator bath near the area of
maximum disruption.
3. Sonicate until the microsphere pellet is dispersed.
BioPlex_6.book Page 229 Friday, September 23, 2011 11:55 AM