Mini-Beadbeater-24

• Power: 115 volts, 60 Hz, 7.5 amps or 230 volts, 50 Hz, 3.7 amps
• Width: 10 in. Depth: 18 in. Height: 12 in. Weight 47 pounds
• Shaking pattern: Uses proven, more efficient near horizontal vial orientation
• Capacity: four to twenty four screw-cap microvials (0.5, 1.5, and 2.0 ml) each containing to 400 mg (wet weight) bio-sample
• Shaking speed: Digitally variable from 2400-3800 strokes/min.  The calculated M/sec "performance" value is greater than all competitive beadbeater-type cell disrupters on the market.
• Throw or stroke displacement: 7/8 inches
• Controller: Digital 0-5 minute with auto reset and 3 programmable presets
• Magnetic lid interlock cuts power to the Mini-BeadBeater-24 if the lid is opened at any time.
• Removable vial-holding cassette
• No imposed motor cool-down-time between each sample run
• The Mini-BeadBeater-24 uses standard screw-cap plastic microvials. Stainless steel microvials or special reinforced polypropylene microvials ( XXTuff vials ) are available for dry- or cryo-milling with steel beads. Eight larger capacity, 7 ml vials can be processed using an accessory vial-holding ring (see Parts and Accessories below).

Buying Tips....

SHAKING TIME:  If you are harvesting expressed proteins, for example, you need close to 100% cell disruption.  But, if you want nucleic acids for PCR amplification, perhaps a partial disruption of cells is acceptable.  Some manufacturers claim disruption times of less than 30 seconds.  That may be fine for PCR work, but not for blotting.

SHAKING SPEED:  Some manufacturers of beadbeaters (bead-mill) machine offer speed settings expressed in an ill-defined term: meters/second.  The term combines measurable shaking speeds with vial displacements to create a unit presumed to define cell disruption power.  Unfortunately, no unit is available that comprehensively defines cell disruption efficiency of bead mill grinding machines.  Were it to exist, such a term would need to take into consideration not only shaking speed and distance of vial displacement, but also shaking direction (vertical vs.horizontal), shaking pattern (linear vs.figure eight), kinetics of change in shaking direction (sigmoidal vs. square wave), vial size and shape and other engineering variables.  Clearly, the interplay of these variables is complex. They must be taken into consideration in the design of a high performance cell disrupter machine and, as might be expected, some machines achieve this goal better than others. Additionally, most published protocols rarely call for shaking speeds below the maximum shaking speed available from the machine.  Thus, speed control, when available, can be viewed as a 'bell and whistle' feature.

FROM THE BIOSPEC 'TECH GUYS':  BioSpec Products was the first to introduce 'beadbeating' cell disruption to the scientific laboratory 35 years ago.  This method of cell disruption for small samples has replaced many traditional methods.  In addition to BioSpec's current five models of beadbeater cell disruptor, about a dozen other manufacturers offer similar microvial-shaking 'beadbeater-type' cell disruptors*.   Most of them are well designed and fulfill criteria for maximum cell disruption performance: Look for machines that have a shaking speed of at least 2000 rpm; a throw (or displacement) of the vial of at least 3/4 inches and a shaking orientation and pattern that maximizes bead circulation within the vial.  As discussed earlier, other factors influencing cell disruption performance are numerous and complex. They cannot be expressed in a simple mathematical formula with units of meters/sec.

Here is a Rule of Thumb for operating any shaking-type, bead mill cell disruption machine offering variable shaking speed, whether made by BioSpec or any other manufacturer:  If the objective is to disrupt cells, crank up the machine and get the job done. Operate the machine at its maximum speed setting.  Special applications requiring lower operating speeds are rare.  Grinding time will vary, depending on the type of sample.  Generally, 2-3 minutes will get you close to total cell lysis.  If you are doing PCR work and can settle for less than 100% lysis, shorter periods of beadbeating may suffice.  Also important for good cell disruption is the choice of bead size, bead composition, and bead load.  These later details are covered in operating instructions that accompany our machines and are also available on our home page under "INSTRUCTIONS"

 If native proteins or intracellular organelles are being recovered, temperature control will be essential.  With most high energy beadbeaters the grinding process increases the homogenate temperature about 10º per minute of beadbeating.  This is most easily done by removing the microvials after one minute of beadbeating and cooling them in crushed ice/water mix for one minute.  Recycle this one minute beadbeat and cooling cyle as necessary.  Temperature control is not as important for nucleic acid extraction in nucleic acid extraction media.

There are three equally important variables under the control of the user which determine efficiency of cell disruption: bead size, bead composition and bead load in the vial. These variables must be optimized by the user, not only for the 'beadbeater' machine which is in use, but for the type of sample being investigated.  While there are commercially available vials prefilled with special bead mixes offering solutions for these three variables, one can usually get equivalent results and at the same time, save money by loading your own beads into vials. Only one kind and size of bead is usually needed.  BioSpec's web site OPERATING INSTRUCTIONS  and our web site Beads (Guide-lines) give straight forward advice on how to do that.  And also, there are our tech guys standing by to help.

NOTES:

For the names and contact details of all commercially available bead mill cell disrupters see Cell Disrupters: A Review.  In addition to shaking cell disrupters there are vortexing bead mill cell disrupters.  Most function like the shaking bead mill cell disrupters but tend to be 5 to 10X slower in achieving complete disruption.  The notable exception is BioSpec Product's NEW SoniBeast™ Cell Disrupter which can disrupt cells at rates up to 10X faster than the current commercial shaking-type beadbeating machines.