One of the largest bottlenecks in a modern life science laboratory workflow is at the beginning of the sample-preparation stage: It is the efficient lysis, homogenization, and grinding of difficult-to-lyse samples. This step is necessary in order to release subcellular and nuclear content for further analysis and workflows, such as to make nucleic acids accessible for purification, amplification, sequencing, or get proteins and metabolites for further analysis.
The main requirement from the life science lysis process is that the fragile macromolecules be released in as intact a form as possible within a reasonable time-frame without introducing additional chemicals to the system, which may interfere with downstream processing. Due to the absence of additional substances such as enzymes, detergents, or corrosives, mechanical sample lysis is the preferred process for use in the preparation of difficult-to-lyse samples.
Mechanical sample lysis can be performed in a variety of ways, with the two most common techniques being the rotor and stator type homogenizers, and a variety of bead-beating systems. The disadvantage of the rotor and stator type of homogenizers is in their inability to process samples that are not already viscous or fluids, or whose outside diameters are larger than the gap between the rotor and stator, making this technique difficult for processing hard samples like most agro-biotech samples including seeds, plants, etc, as well as for many solid tissues.
In addition, the rotor and stator homogenizer cannot perform lysis in a dry state, which is the preferred method for some types of analysis. Bead-beating systems use hard mineral or metallic beads to impact a sample and break it mainly by cascade impaction. Mechanical bead beating-based homogenization can be done in a dry or wet state.
The most efficient bead-beating systems are the ones that create a strong multidirectional force field, making it possible for three different grinding processes to simultaneously act upon a sample. These processes are 1) cascade impaction, a hammer-like process of beads beating on a sample, 2) mechanical shearing by sharp edges of lysing beads travelling through the enclosed volume of a sample container and colliding with samples at different trajectories with different velocities and if lysis/homogenization is performed in a buffer, i.e., liquid media, 3) the shearing of the vortex flow generated due to the multidirectional abrupt shaking of the fluid.
There are several well-established commercial systems that perform sample homogenization, grinding, and lysis of the most difficult samples within the time-frame of 20–40 seconds based upon bead beating in an omni-directional force field; however, all of them are priced in a range from $6,000 to $20,000 in the U.S. market and all are benchtop models, not amendable for field use.
In this article we describe a novel system for ultra-fast sample lysis, homogenization, and grinding based upon omnidirectional bead beating in a handheld tool-like format, for the first time thus allowing processing of the most difficult samples, such as corn kernels, seeds, and soil in situ. This novel, patent-pending system is ultra-fast and can perform complete, quantitative dry or wet homogenization of a corn kernel in five seconds. It can be also considered as an affordable high-throughput sample-preparation lysis system for both field and laboratory use.