Bullet Blender Beads

Overview	Bead Use and Selection	FAQ	Protocols

Frequently Asked Questions

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 hours 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. 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.

Q: How do I separate beads from the homogenized sample?

A: After homogenization, spin your tubes in a centrifuge for a few seconds. The beads will pool at the bottom of the tube. Remove the homogenate with a pipette and dispense in a fresh tube.

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