Stirring Bars and Rods
Products of various sizes, shapes, and material compositions designed to aid in manual or automatic stirring of laboratory solutions. Includes glass stirring rods, magnetic stir bars, and stir bar retrievers.
What Is a Magnetic Stir Bar?
Magnetic stir bars are stirrers or stirring hotplates used with magnets to mix a liquid or solution by creating a vortex.
A number of factors affect magnetic stir bar efficiency and effectiveness, including its size, shape, and material. Sizes (L x Diameter) range from 2 x 2 mm to 159 x 27 mm and shapes include:
- Polygonal or octagonal magnetic stir bars are the most common shapes; the multiple surfaces add turbulence to the mixing action
- Elliptical or egg-shapped stir bars work especially well with round-bottom flasks
- Wedge-shaped spin bars produce more significant turbulence for dissolving salts or in samples containing sediment
- Spin bars with fins or vanes, designed for smaller vessels, tubes, or cuvettes
- Micro (“flea”) stir bars for mixing extremely small samples
What Kind of Magnet Is Used?
Stir bar magnets are typically made from Alnico, a combination of aluminum and nickel. They may also be made from Samarium cobalt, a rare earth metal that produces the stronger magnetic force needed to mix very viscous substances.
Stir bar magnets are usually encapsulated in white or colored PTFE, hard plastic, or borosilicate glass, and coatings may meet FDA grade or USP requirements. PTFE is durable, inert, and can be autoclaved. Glass-encased cylindrical magnets are useful for high-temperature applications.
How Does It Work?
During the stirring process, integral or removable pivot rings on the stir bar reduce contact with the vessel to help avoid marring plastic surfaces. Some round stir bars have slightly raised ends that create a de facto pivot point, while others have more pronounced round centers that help to keep them in motion. Stir bars may be reusable or disposable.
Magnetic stir bars may be sold individually or in magnetic stir bar kits that include multiple bars in a range of sizes.
Chemglass Life Sciences Stir Bar, Micro, Magnetic, PTFE, Length x Dia. in mm: 3 x 3
Stir Bar, Micro, Magnetic, PTFE, Length x Dia. in mm: 3 x 3. Micro PTFE stir bar for the very smallest containers. Manufactured with FDA-grade and USP Class VI PTFE.SEE CG-2003-50 FOR STIR BAR KIT
Cole-Parmer DWK Life Sciences (Kimble) Stir Rod, Glass, 5 mm dia X 150 mm L, 25/pk
Manufactured with borosilicate glass with rounded annealed ends. Stir rods are highly chemical resistant and withstands temperatures to 400 F (205)C. Autoclavable.
Biosurface Technologies Corp Industrial Surfaces Biofilm Reactor with 220V Stir/Hot Plate, Low- to Mid-Shear Laboratory Biofilm Growth Device, BioSurface Technologies Corporation.
"The Industrial Surfaces Biofilm Reactor (ISBR) is a bench-top biofilm growth chamber designed to provide a growth environment for biofilm under low shear, high gas transfer, and intermittent wetting. The sample slides are intermittently wetted via a fluid distribution port in the reactor. The nutrient feed gravity flows into a sump located at the bottom of the reactor and may be recycled or drained to waste. This reactor environment is similar to those in industrial cooling towers, food preparation surfaces, painted and coated surface testing, marine environments, and other periodically wetted or humid biofilm growth surfaces. The ISBR can be used to model biofilm growth found in a large variety of industrial applications and public health environments.The components of the ISBR include: multi-ported glass vessel, ported lid, lid seal assembly, coupon holder rotor, fluid distribution port, 18 coupons (various materials available).
Analytical Sales & Services Well Tray Loaded with 8x30 Shell Vials, with 99685 Silicone Cap Mat, and 13258 Stir Bars
Well Tray Loaded with 8x30 Shell Vials, with 99685 Silicone Cap Mat, and 13258 Stir Bars