Hand-operated device especially useful for crushing bone and teeth samples.
A compact, low cost screw-press designed to pulverize 50-500mg of hard, brittle material such as bone or teeth. If fresh tissue is used, the sample is cooled in liquid nitrogen to make the tissue hard and brittle, inserted into in the pre-cooled pulverizer 'nut' and then crushed by manually screwing together the two screw plungers. The end result is tissue powdered to the size of grains of table salt or smaller. Use as a preliminary step to homogenization or extraction which then will proceed quickly and efficiently using one of several standard cell disruption methods. For cryo-pulverization of soft or elastic tissue, see the BioPulverizer.
Instructions For Use:
- The MicroCryoCrusher consists of a oversized nut and two knobs containing threaded plungers, one long and the other short.
- Precool the MicroCryoCrusher metal parts in liquid nitrogen. Thread the short plunger 1/2 way into the Nut. Place prefrozen sample into the open end and insert the long plunger. The large mass of the cold stainless steel nut will give you ample time to complete step 3 without additional liq.N2 cooling.
- Hand tighten the plunger knobs to compact and crush the tissue sample. Do not use tools to tighten. Occasionally some bone splinters may remain uncrushed. Loosen one of the plungers, rap the MicroCryoCrusher on the bench to reposition the bone material and retighten the plunger 3-4 times.
- Remove the short threaded plunger (marked with green) and expel the pellet of compacted, pulverized bone by screwing down the long screw plunger.
- Exposed, powdered tissue thaws rapidly, so proceed to the next step of homogenization or extraction promptly.
For more information on the origin and use of this device see Preparation of Bone Samples for DNA Extraction: A Nuts and Bolt Approach, M.G. Thomas and L.J. Moore, BioTechniques, Vol.22, p.402 (1997).
- Stainless steel (type 316) and 3 inch dia. phenolic plastic knobs
- 'Nut' dimensions: 1 inch X 1 inch with a maximum sample volume 0.8 cm3