Effective disruption of biological samples is a process that starts with sample collection and proceeds through the homogenization process. To generate a homogenate that is suitable, it is prudent to define the characteristics required in the final product and then choose the best method or combination of methods that will produce that product.
Chemical and mechanical methods, by themselves, can be used to disrupt samples, but normally are used in some combination to achieve a desired homogenate. At a minimum, buffers, chaotropes, and surfactants are common additives that help to solubilize and maintain biomolecules released during mechanical processing. For the isolation of biomolecules which are labile or sensitive to degradation, protective chemistries partnered with a mechanical method are necessary to obtain quality homogenates.
All methods used to disrupt samples have strengths and weaknesses. Lower throughput methods can be used to process larger samples with good results, and many are economical. High throughput methods are also effective, but the initial investment will be greater.
Many tools when used alone to homogenize samples are not as effective at disrupting samples but when combined with each other can be very useful. Ultrasonication is the classic example as it is a poor method when used on solid samples, such as muscle, but yields the best results when combined with an early processing step. Many of the shearing methods produce fine homogenates, but fail to disrupt all tissues. They can be valuable in producing lysates with intact subcellular components. Bead beating with high throughput homogenizers can be a very effective one-step homogenization method.
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