Probe sonicator, Bath sonicator, Enumeration of xmap microsphere suspensions – Luminex 100 IS Version 2.1 User Manual
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Luminex 100 IS Developer Guide to xMAP Technology Version 2.1
x
MAP
Technology
66
PN 89-00002-00-062 Rev. A
sonicating are not recommended for the larger vials as they are not
effective in resuspending the microspheres or preventing
aggregation.
Over time, it is normal to observe a presence of beads on the surface
of the liquid in the stock vials. You may also notice a container wall
residue and suspended macrobead aggregates. While these conditions
are typical, the severity may increase with repeated opening and
pipetting from the vials. Limiting the number of times a stock vial is
opened reduces the risk of photobleaching and possible bacterial
contamination as well. For these reasons, Luminex recommends
ordering a volume of the microsphere stock that is closest to the
amount of microspheres you will need in a single use.
The following are two indirect sonication methods that are effective
at separating aggregates in closed containers of microsphere
preparations.
Probe Sonicator
To disperse a microsphere pellet using a probe sonicator in 1 mL
volumes:
1. Place probe tip in a small bath of water.
2. Insert the end of the microsphere tube near, but not touching, the
tip of the sonicator probe. Do not immerse 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 in 1 mL
volumes:
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.
Enumeration of xMAP
Microsphere Suspensions
Luminex xMAP microspheres are provided at standard
concentrations. The xMAP microsphere yield after a coupling
process may be less than the starting concentration due to loss during
wash steps. The xMAP microsphere loss can vary according to
operator technique, coupled reactant properties, and scale of
coupling.
Note:
Inserting a sonicator
probe into preparations is
not recommended.