BioHomogenizer Operating Instructions
- Chop or cut tissue into small pieces (< 5 mm in size) using a scalpel, safety razor blade, or scissors. Especially relevant when the isolation of nucleic acids is the goal, if a tissue sample is large and is stored prefrozen do not thaw the sample. Instead, break the sample into small pieces by cryopulverization (see BioPulverizer).
- Place the tissue in a homogenizing vessel containing the equivalent of 3 to 10 tissue volumes of the homogenizing medium.
Lower the probe into the tissue suspension before turning on the BioHomogenizer and operate for 5 seconds to 2 minutes using an up-and-down dabbing motion. Do not immerse the probe more than one-half its length into the homogenization solution. Use lower speeds for subcellular particle preparation and maximum motor speed for biochemical extractions. When processing numerous samples, the BioHomogenizer can be stand-mounted using a tri-clamp and ring-stand.
- To avoid splashing, turn off the Tissue-Tearor before withdrawing from the homogenizing vessel.
- Place the BH upright in its stand when not being used so that any liquids that have worked their way inside the probe can drain out. Do not leave it positioned on its side.
Prompt cleaning of the BioHomogenizer is important. Biological material and extraction media can be surprisingly corrosive, even if the probe is stainless steel. If biomaterial gets into the upper part of the probe and into the motor, its lower motor bearing may be destroyed. Between repetitive processing samples, the unit can be superficially cleaned by briefly sequentially operating the BioHomogenizer in one or more vessels containing water. At the end of the work, unscrew the outer part (stator) located at the lower part of the probe shaft by turning it clockwise (it has a left-handed thread), pull off the rotor and clean them in detergent. When dry reassemble them on the probe shaft. The stator and rotor can be autoclaved but the rest of the probe (probe shaft) cannot be autoclaved. Instead, wipe it down with a 1 to 10 dilution of household bleach followed by a sterile water rinse.
From time to time remove the stator and rotor, hold the BH upside-down and add a single drop of mineral oil to the probe shaft. Do not use a petroleum-based lubricant. Run the BH in this inverted position for 30 seconds. Wipe away any excess lubricant and reattach the rotor and stator to the shaft.