Bio-Rad Bio-Plex Pro Human Acute Phase Reagent and Diluent Kits - Manual (Page 12)

Section 6
Sample Preparation
This section provides instructions for preparing samples derived from
serum, plasma, and culture supernatant. For sample preparations not
mentioned here, consult the publications listed in Bio-Rad bulletin 5297,
available for download at www.discover.bio-rad.com
Serum and Plasma Samples
Collect and process the serum or plasma samples and assay immediately
or freeze at –20ºC. Avoid repeated freeze-thaw cycles. EDTA is the
recommended anticoagulant for preparing plasma samples. Extremely
lipemic samples may be filtered with a 0.22 µm filter to prevent clogging.
Hemolyzed samples are not suitable for Bio-Plex Pro™ acute phase
assays.
1. After collecting blood samples, immediately add appropriate
inhibitors according to manufacturer’s instructions if necessary, invert
tube several times to mix.
2. Prior to assay setup, centrifuge the samples at 13,200 rpm for 10 min
at 4ºC to clear the samples of precipitate. Alternatively, carefully filter
the samples with a 0.22 µm filter to prevent instrument clogging.
Keep samples on ice until ready for use.
3. Refer to the steps and the table below for sample dilution instructions
for preparing the 5-plex assay, the 4-plex assay, or for preparing
samples for the 4-plex and 5-plex assays at the same time.
5-plex assay:
Dilute 5 µl of sample in 495 µl of serum free
diluent. Mix by vortexing gently or pipetting. This results in a
final 1:100 sample dilution.
4-plex assay:
First dilute 5 µl of sample in 495 µl of serum-free
diluent to create a 1:100 dilution. Mix gently. Next, dilute 5 µl of
this mixture into an additional 495 µl of serum-free diluent. Mix
gently. This results in a final dilution of 1:10,000.
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