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 Stabilizer Bars, Set of Three, for 15L Bioreactor Stands
Six-inch long bar attaches to legs of 15 liter stands and adds an additional measure of safety to the 15 liter bioreactor.Sold as a set of three.Like-for-like replacement parts for Applikon Biotechnology and Broadley-James brands of bioreactors.Applikon is a registered trademark of Applikon Biotechnology, Inc.Broadley-James and Broadley-James Corporation are registered trademarks of Broadley-James Corporation.
Chemglass Life Sciences Stir Bar, Magnetic, Egg-shaped, fits 12000mL-22000mL flask, Length x Dia. in inches: 3 x 3/4
Stir Bar, Magnetic, Egg-shaped, fits 12000mL-22000mL flask, Length x Dia. in inches: 3 x 3/4. Egg-shaped magnetic stirring bar provides its own pivot point without separate ring or abrupt change in contour. Designed for use in round bottom vessels, it is shaped to spin freely, unrestricted by the vessel contour. Manufactured with FDA-grade and USP Class VI PTFE.SEE CG-2005-20 FOR STIR BAR KIT
Azzota Corp Magnetic Stirring Bar - Z Type, 25mm Length, Dia. 6mm
Magnetic stirring Bar - Z type, 25mm length, Dia. 6mm
Cowie Technology Corporation REMOVABLE RING STIR L25MM D8MM
This item has a minimum qty of 47 per supplier requirements.
Stirbar, removable ring, length 25 mm, diameter 8 mm
Electron Microscopy Sciences Spinbar Magnetic Sink Strainer, Blue
Just drop in place and prevent magnetic stirring rods from going down the sink. Made from a durable and flexible material. Includes four strong magnets to capture the magnetic stirring bars before they go down the sink drain. Features long slits so fuilds drain easily and rapidly and a wide skirt that can be used with a variety of sink drains. Four legs located on underside anchors the strainer firmly in the sink drain. One size fits most laboratory sinks.
Cole-Parmer Mono-Mold Standard Stir Bar with Spinning Ring, 1"L x 3/8" dia
Mono-Mold magnetic stir bars are the standard all-purpose stir bar. Available with or without spinning rings; rings reduce contact area between stir bar and vessel, reducing friction and noise.
Cowie Technology Corporation HUB STIRBAR 62MM L 37MM D
This item has a minimum qty of 10 per supplier requirements.
Stirbar, hub, length 62 mm, diameter 37 mm
Cowie Technology Corporation GIANT PLAIN STIRBAR L57MMD27MM
This item has a minimum qty of 8 per supplier requirements.
Stirbar, giant plain, length 57 mm, diameter 27 mm
Sigma Aldrich Fine Chemicals Biosciences SpinbarR magnetic stirring
Very small efficient stirring bars. Ideal for vials micro test tubes centrifuge tube mixing etc.PTfE(R) PTfE coatedALNICO V coated magnet