From Rockers to Orbital Shakers – What Type to Use for Shaking Cultures?
Rocking, linear or orbital shaking – three different agitation modes all with the same purpose to mix samples. Still, there are differences in the technology behind as well as in the related instruments in the lab. Learn more about the shaking processes and its applications in the lab.
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Shakers agitation modes range from slow rocking in a 2- or 3-D plane over figure-eight, up to a back- and-forth linear or orbital motion. Common to all of them is to move a top mounted platform in a certain way with the purpose to put the liquid in the vessels in motion. As shakers are used in the lab for a variety of applications from chemical extractions, over washing and staining procedures up to cell expansion, different shaker types developed over time. Not all types are equally suited for all applications.
Shakers have been used to cultivate cells since the beginning of the last century. No matter if it is a microbial, algae or mammalian shake culture, the purpose of shaking is to increase the availability for nutrients and to improve the oxygen transfer to gain a higher biomass compared to static incubation. Beside that results should be reproducible to make parallel experiments comparable. What mode of agitation is best suited for cell expansion and what mode is more appropriate for applications in molecular biology?
The Soft – Gentle mixing with rockers
Rockers move the platform either in a two or in a three-dimensional see-saw motion about the central point and usually run at low rpms < 100 rpm. They create a wave-like mixing process and are used – generally as benchtop devices – for gentle mixing and incubation procedures e.g. in molecular biological applications, like DNA extractions, staining and de-staining and washing procedures of blots and gels. In terms of cell cultivation specifically constructed rocking devices evolved allowing the cultivation of mammalian cells in single-use bags.
The Turbulent – Breaking the waves with reciprocating shakers
The Consistent – Continuous swirl with orbital shakers