The breadth of this field reflects the wide range of applications. Shakers mix solutions for chemists, molecular biologists, physical scientists, and others. Many users, though, seek a particular style of shaking. “End users are reaching out for a very specific motion that they require for their applications,” says Nicole Kvasnicka, product marketing manager at Heidolph, headquartered in Schwabach, Germany. “They need to be very specific to not damage their samples.”
A range of specifications describes what a particular shaker does. Typically, a user looks for a shaker that provides a specific speed, often described in revolutions per minute (rpm), and one that carries a certain load, such as a number of flasks. For a shaker that moves items back and forth, the user might care about the stroke length—how far the carrying tray moves from left to right. Some users even want a shaker that goes from stop to stop in a specific amount of time.
Finding the right tree in the forest
The shaker market resembles a rainforest, with each tree depicting a product. It’s very dense out there. “Every lab company offers a shaker,” says Kvasnicka. “So compare features of load capacity and speed.” She adds, “You need something that provides longevity, because you need to know that the shaker is still working even if you leave it on a thirty-hour run.”
Beyond the specifications, a shaker must treat samples the same way time after time. As Daniela Dockweiler, head of application support at IKA, headquartered in Staufen, Germany, says, “Reproducible analysis has become indispensable.” To help with that, says Dockweiler, “Almost all IKA shakers feature an integrated timer that allows for unattended operations.” For even further options for walk-away shaking, she says, “The control models feature an automatic end-positioning that allows IKA’s shakers to be used in automated applications. In addition, the control models can be operated through the RS 232 port.” Such computer-controlled shaking can benefit many applications, and that’s a feature worth considering. As Dockweiler says, “These technologies make it possible for robots to fill and extract samples.”
In addition to getting the right shaker, users need the right accessories. Most manufacturers offer a wide range of add-ons for shakers, including platform attachments for different glassware.
Michael Evans, freshman chemistry laboratory coordinator at Georgia Tech in Atlanta, has used a shaker for hydrogenations, and he says, “Ease of operation in general is pretty important. For example, fittings should be straightforward to use, versatile, and robust.”
Shaking for separation
Beyond mixing, shakers can perform other tasks. For instance, sieve shakers can separate particles of a wide variety of sizes, depending on the particular shaker. These shakers get used in many applications, including work with anything from coffee and construction materials to sand and soils.
In this shaker market, customers seek different requirements. As Kyle James, president at Verder Scientific, which is the new corporate name for Retsch and Carbolite in the United States, located in Newtown, PA, explains, “There has been more demand for calibrated sieve shakers and [installation qualification/ operational qualification] documentation for these sieve shakers.” Consequently, James’ company developed a line of sieve shakers that provide this documentation.
In terms of the sieve shakers themselves, James doesn’t see much change going on inside. He says, “The technology in sieve shakers has not changed over the years.” He adds, “Many clients now have facilities in many countries around the world and are always concerned about reproducibility of the sieve analysis when compared across facilities.” To deal with that issue, says James, his company offers shakers that “use a ‘sieve acceleration’ mode that allows the sieve shaker to operate independently of the main’s frequency—50Hz versus 60Hz—in various countries, which influences the sieving operation.”
Beyond being able to move a device around the world, users want simplicity in the day-to-day use of a sieve shaker. When discussing ease of use, James says, “This often affects which clamping system is combined with the unit to allow the customer to easily install and remove the sieve stack and sample.”
At the very beginning of shopping for a sieve shaker, though, keep in mind the fundamentals. As James explains, “Some customers just want a very basic sieving operation, while others need a high level of calibration and accuracy. This determines the appropriate model that should be purchased.” He adds, “We see customers make ordering mistakes by just purchasing a basic sieve shaker, and then coming back to us and asking why it does not have additional features or settings.”
To keep your shaker shaking, there’s not much to do, if you bought a good one. As Kvasnicka says, “Shakers are pretty much workhorses. You set the timer, turn it on, and it shakes.”
To keep shaker maintenance to a minimum, look for a product with a no-maintenance motor. In addition, Kvasnicka says, “We use a sealed housing that protects the shaker from liquids and vapors.”
Even with a shaker developed for continuous operation, some environmental factors must be considered. Dockweiler points out that “external conditions, such as temperature and humidity, should be monitored.”
Although shakers are lab workhorses, nothing works perfectly, especially not forever. Some companies offer a warranty on a shaker for a few years. Others offer customer service in selecting the right shaker and keeping it running properly.
Follow a few guidelines, shop carefully, and then you can join Jerry Lee—“shake baby shake.”
For additional resources on Shakers, including useful articles and a list of manufacturers, visit www.labmanager.com/shakers