Selecting a High Capacity Cell Disrupter
To date there are five High Throughput Bead Mill Cell Disrupters on the market capable of using 96-well microplates: The MiniBeadbeater-96, the Model 2010 Geno/Grinder, the Talboys Homogenizer,the Retsch MM 301 and the FastPrep-96. A fifth alternative, a commercial paint shaker, has proven to be unacceptable for most applications. The shaking motion of paint shakers rotate or resonate about a central axis, thus giving non-homogeneous cell disruption across the microplate platform.
When 'shopping' for a commercial High Throughput Cell Disrupter there are several important features to consider. Sample capacity and price are obvious and important considerations, but one should also look at vial orientation during shaking (for example, vials with the axis oriented close to horizontal and the shaking action in the same direction are disrupted more efficiently than vials held in an upright position and shaken in an up/down motion). Both high shaking speeds (2000 +/- 200 oscillations/min) and adequate shaking distances or 'throw' (1.0 +/- 0.25 inch) are also important. Compromise on either of the later two properties in the vial shaker and it can take up to 10X longer to get good cell disruption. Put another way, there are several variables that account for 'efficient' cell disruption. If you are harvesting expressed proteins, for example, you need close to 100% cell disruption. 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's fine for PCR work, but not for blotting or protein expression analysis.
Perhaps the most important consideration is high shaking energy (for example, see 'Retsch MM 300 vs. BioSpec MBB-96', below). It takes a big motor to get the job done and some machine designs have compromised with a smaller motor which heats up quickly. Their hard-wired protocols impose limited beadbeating times (60 secs or less) and required cool-down periods of 1-5 minutes between runs.
Another desirable feature is the capability to shake either vials or microplates on the same machine. And look for an efficient, easy-to-use plate or vial clamping mechanism. Microplates should be clamped into a holder designed to press the entire surface area of the mat or membrane to the surface of the microplate. Finally, efficient cell disruption almost always requires the highest available shaking speed (see above). It is very rare to use speeds below the optimal range for cell disruption. Speed control on a machine can be considered somewhat of a 'bell and whistle' feature.
A comparison. Retsch MM 300 vs. BioSpec MBB-96: The BioSpec Products MBB-96 is a much more powerful shaker than the Retsch MM 300. Compare a 1288 watt motor versus 184 watt motor. In addition, it is significantly less expensive - compare $5484 versus $7500-$10,000 (or more). Our MBB-96 cell disrupter has a two year warranty and, being made in the USA, can be quickly serviced, if needed.
From a performance standpoint, the high power of our MBB-96 cell disrupter assures complete cell breakage in three minutes or less using low cost glass or ceramic beads. Because of this superior shaking energy it does not require the use of heavier, more expensive (and sometimes contaminating) stainless steel or tungsten carbide beads. While less energetic machines will disrupt cells, it can take a order of magnitude longer to get equivalent good cell disruption (we know because we built weaker machines in the course of developing the final MBB-96!). If extracting nucleic acids, we counsel our users to do the cell disruption directly in the nucleic acid extraction media, thus shortening extraction time and eliminating possible degradation of the RNA or DNA. Extraction media can be prepared 'in house' or purchased from various commercial 'kit' manufacturers. The MBB-96 holds either 48 standard microtubes (which can be kept cold in an accessory solid aluminum block, if desired), one 2 ml 96-deepwell microplate, two 1ml 96-deepwell microplates, or four standard sized microplates.
Bottom line: The MBB-96 is more powerful, faster acting, and sells at a lower price. Sample capacity is equal to or exceeds that of competitive machines. BioSpec Products, the company who first introduced the 'beadbeating' technique for cell disruption into the laboratory over thirty years ago, is a quality source for technical expertise and prompt service.
Comments from a Researcher at Lawrence Livermore National Lab*:
'We have now tested the MiniBeadBeater-96 with two different sets of samples, with more than 100 samples processed. It seems to perform comparably with the single channel units we have from BioSpec, which is a very pleasant surprise. We are able to isolate DNA from purified Bacillus spores, which have proved to be too difficult for all of the other commercially available, multi-channel instruments we have tried.'
*Not to be taken as an endorsement by LLNL or its affiliates.
.....from Ontario Veterinary College:
'We received your MiniBeadbeater and put it to use immediately. It is just as advertised, easy to use, and our tissue homogenization and resultant RNA isolation has improved drastically!!
.....from Steve @emu.edu:
I'm shopping around for a bead-beater kind of homogenizer, and the mini-bead beater 16 looks great, price-wise anyway, compared to the Fastprep and other similar products.
How does it compare to the other $7000-$10000 bead beaters on the market and why is it so much cheaper?
Answer: For over 30 years our philosophy has been to offer novel scientific equipment at reasonable prices. BioSpec accomplishes this in two ways:
1. We sometimes design and build equipment around preexisting mass-marketed tools and appliances (example: The 'TissueTearor' homogenizer uses a Dremel-tool motor). The savings from this strategy are passed on to the customer.
2. We advertise modestly. For product promotion we mostly rely on 'word-of-mouth' and scientific literature references. Print and internet advertising, distributor discounts, representative commissions, trade shows, mock customer discounts, in-house demonstrations and other forms of marketing are expensive. In many cases, over 50% of the established list price of a lab tool must cover these marketing costs!