Bead
Sample Packs
Sample packs come with a 10 ml tube of each type of included bead, EXCEPT the BSP-50B, which comes with 20 ml of each type of bead (in 50 ml tubes).
Bead Sample Pack for
homogenizing cell cultures (BSP-CC) ........... $65
Includes
0.1mm glass, 0.15mm ZrO2,
and 0.2mm stainless steel.
Bead Selection Guide
We
provide a
selection of beads in
order to provide you with choices in your protocols and
applications. Denser
beads
provide more mass at the same volume and are therefore recommended for
tougher samples. Please keep in mind that the recommended bead size will vary based on the size of your samples - small beads are best for cell culture and very small pieces of tissue, and larger beads are better for larger pieces of tissue. There are many combinations which will work
for
your
samples.
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Bead Calculator
Since the bead amounts are based off of a mass ratio, we have provided a simple way to know how many beads you will need to obtain a certain mass. Our bead tables table is below, and a version complete with a bead calculator is available for download in OpenOffice Calc and Microsoft Excel formats.
Useful estimation - a full scoop with the bead spatula will hold about 50 microliters of 1mm or smaller beads, and you can often approximate the appropriate amount of beads by volume by using a 2:1 sample-to-bead volume ratio. Please know that scoop size may vary with different sized beads or because of human error, and the amount of beads required may change based on the protocol. If you find that measuring by volume causes inconsistency, then go back to measuring by mass.
| Bead |
Diameter (mm) |
Density
(mg / microliter) |
Weight (mg) |
Beads per 100mg |
100 microliters* of beads (mg) |
| Glass |
0.10 |
2.5 |
0.0013 |
76000 |
175 |
| Glass |
0.50 |
2.5 |
0.16 |
610 |
175 |
| Glass |
1.00 |
2.5 |
1.3 |
76 |
175 |
| Zirconium Silicate |
0.50 |
3.8 |
0.25 |
400 |
266 |
| Zirconium Silicate |
1.00 |
3.8 |
2.0 |
50 |
266 |
| Zirconium Silicate |
2.00 |
3.8 |
16 |
6.3 |
266 |
| Zirconium Oxide |
0.15 |
5.5 |
0.0097 |
10000 |
385 |
| Zirconium Oxide |
0.50 |
5.5 |
0.36 |
280 |
385 |
| Zirconium Oxide |
1.00 |
5.5 |
2.9 |
35 |
385 |
| Zirconium Oxide |
2.00 |
5.5 |
23 |
4.3 |
385 |
| Stainless Steel |
0.20 |
7.9 |
0.033 |
3000 |
553 |
| Stainless Steel |
0.50 |
7.9 |
0.52 |
190 |
553 |
| Stainless Steel |
1.60 |
7.9 |
17 |
5.9 |
553 |
| Stainless Steel |
3.20 |
7.9 |
140 |
0.74 |
553 |
| Stainless Steel |
4.80 |
7.9 |
460 |
0.22 |
553 |
*Note - With larger beads or with small containers, the efficiency of packing may be reduced. Please be aware of this and make adjustments as appropriate when measuring beads by volume.
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Frequently
Asked Questions (FAQs)
This is the FAQ specifically for beads. We have a separate FAQ for the Bullet Blender itself.
Q: Can I
wash and reuse the beads?
A: Yes you can! Many protocols that recommend acid washing use
concentrated hydrochloric acid. This is fine for glass beads
which are inert to hydrochloric acid, but it reacts with the surface of
zirconium oxides generating reactive ceramic intermediates which may
interfere with your experiment. We
strongly advise against acid washing zirconium based beads.
We also advise against acid washing stainless steel beads due to potential
corrosion. Most Bullet Blender users choose to simply dispose of the beads after use since they are fairly inexpensive.
Q: How
do I wash the beads?
A:
Washing in standard laboratory detergent (like Alconox®),
followed by rinsing with deionized water to remove detergent is
sufficient. Make sure that no soapy bubbles remain
before allowing the beads to dry.
Q: Are
the beads RNase free?
A: Not unless specified.
You can treat non-RNase clean beads with a reagent like RNAZap® or
RNaseAWAY®,
followed by rinsing with nuclease free/DEPC treated water.
Allow the beads
to air dry in an oven or at ambient temperature. Testing is
required to determine the degree (or lack thereof) of nuclease activity
before and after treatment. Alternatively, baking the beads
at
high temperature (450°F / 232°C) for two ours or more
has been
shown to inactivate RNases.
Q: Will
the beads stick together when I wash them?
A: After
washing, the beads may stick together upon drying. Gently
shake the container with the dried beads until they flow freely.
Q: How
many times can I reuse the beads?
A: You
may wash and reuse the beads many times. How many uses you can get out of a batch of beads will depend on sample hardness and the speed at which you run the Bullet
Blender™. Typically, you can reuse the beads about ten times. Stop reusing
the beads when cracks appear or there is noticable wear, including discoloration.
Q: Do the beads need any preparation?
A: For protein or DNA applications you may autoclave the beads, otherwise they do not require additional preparation. For RNA extractions,
we recommend washing the beads with RNase Zap® (Ambion, Inc.) or RNase Away®
(Molecular BioProducts), then rinsing with nuclease free water,
followed by autoclaving.
Q:
How do I sterilize the beads?
A: They
can be autoclaved on dry cycle to sterilize them. They may
stick, so shake the container with the dried beads until they flow
freely. Alternatively, they may be gamma irradiated or
exposed to ethylene oxide. Any manipulations of the beads
after sterilizing must use aseptic techniques in order to preserve the
beads' sterility.
Q:Which
beads are good for homogenizing which samples?
A: Check
the Bead
Selection Guide above. The two basic rules: (1) use beads of approximately
the same size as the size of your samples, to maximize the collisions
between beads and samples, and (2) use denser beads for tougher
samples. |
