Bio-Rad Bio-Plex® 200 Systems User Manual

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Turn on the laboratory vacuum to maximum level (the same level that was used in the
preceeding calibration procedure).

Press on the filter plate and note the time required to evacuate the solution from the wells.
The time required should be 2–5 sec.

Note: It is important to perform this step exactly as you would perform a wash step in a
Bio-Plex assay.

If the time required to evacuate the solution from the wells was less than 2 sec, the calibrated
pressure is too high. If the time required is greater than 5 sec, the vacuum pressure is too
low.

If the pressure is too high (evacuation occurs too quickly), open the vacuum control valve
slightly (so that fewer colors are showing) and repeat steps 1 through 5 until the evacuation
time is 2–5 sec.

If the pressure is too low, (evacuation occurs too slowly), close the vacuum control valve
slightly (so that fewer colors are showing) and repeat steps 1 through 5 until the evacuation
time is 2–5 sec.

Note: It is a good practice to validate the vacuum pressure each day during the prewetting step
of the Bio-Plex assays. When you have added the assay buffer to the appropriate wells and
evacuated the plate on the manifold, ensure that the time required to evacuate the plate is 2–5
sec. This will verify that the manifold is calibrated correctly.

Tips

Listed below are a few key hints and recommendations for using the vacuum manifold. For a
more complete listing of potential problems and solutions, consult the troubleshooting guide at
the end of this manual.

If you notice a large amount of fluctuation in your pressure using laboratory vacuum, you
may need to purchase and attach a pressure regulator to the vacuum line. Alternatively,
you may purchase a vacuum pump to ensure optimal steady-state pressure. In either case,
it is critical to correctly calibrate and validate the vacuum pressure before performing
Bio-Plex assays.

If you notice that the plates are taking an extended amount of time to evacuate, you may
need to replace the gaskets. See the Millipore multiscreen separations system user guide
for instructions on replacing the gaskets.

Do not allow the laboratory vacuum to continue aspirating the filter plate for more than
10 sec after the solutions are completely gone from the wells. This will result in a
significant loss of beads.

It is recommended that you clean the manifold regularly. The frequency depends on the
reagents you use and how often you use the manifold. Use mild soap or standard laboratory
detergent, bleach, or alcohol to clean all surfaces.

3.13 Performing System Validation

Prior to performing analyses with the Bio-Plex 200 system the instrument must be calibrated.
Calibration should be done each day after startup is complete and the system is warmed up.
You should also recalibrate if the instrument temperature changes by more than 2°C.

The user should verify that the system is performing according to specifications using the
Bio-Plex validation kit. Validation should be performed monthly. Additionally, the user should
revalidate each time the array reader is moved or if there are problems with the array reader
that can’t be solved by other procedures. See the validation kit manual for complete system
validation instructions.