Luminex 100 IS Version 2.2 - Manual (Page 82)

Luminex 100 IS Developer Guide to x MAP Technology Version 2.2 x MAP Technology
76 PN 89-00002-00-032 Rev. A
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.
Note: Inserting a sonicator probe into preparations is not
recommended.
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
microsphere suspensions
Luminex x MAP microspheres are provided at standard
concentrations. The microsphere yield after a coupling process may
be less than the starting concentration due to loss during wash steps.
The microsphere loss can vary according to operator technique,
coupled reactant properties, and scale of coupling.