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.
Electron Microscopy Sciences KOMET™ Spinbar Stirring Bar
The "PTFE" Komet Spinbar Magnetic Stirring Bar is made from a high-energetic magnetic material. That, combined with its octagonal shape, produce exceptional power although its length is only 50 mm (1.969" with a 21 mm (.827") diameter. The Samarium-Cobalt magnet is encapsulated in "PTFE". Its eight edges generate strong turbulence so liquids are thoroughly mixed and its stability is not impaired in vessels with curved bottoms. In addition, the risk of demagnetization caused by external magnetic fields is completely eliminated. Komet transmits torque loads 2 to 3 times larger than those of conventional stirring bars of this length significantly improving efficiency.
Chemglass Life Sciences Plain PTFE Magnetic Stirring Bar, 50 x 8 mm, for Magnetic Stirrers
Plain PTFE-coated magnetic stirring bar (50 x 8 mm) for general-purpose laboratory mixing on magnetic stir plates. Its cylindrical plain profile provides effective agitation and produces increased turbulence at low speeds, while the PTFE coating offers chemical resistance and a non-stick surface.
- Plain cylindrical shape for general-purpose stirring.
- Dimensions: 50 x 8 mm.
- PTFE coating provides chemical resistance and non-stick surface.
- Produces increased turbulence at low stirrer speeds.
- Compatible with standard magnetic stir plates and laboratory mixers.
- Sold individually for easy replacement.
Azzota Corp Ptfe Magnetic Stir Bar Retriever, Length: 13" (350mm)
PTFE Magnetic Stir Bar Retriever, Length: 13" (350mm)
Azzota Corp Ptfe Magnetic Stir Bar Retriever, Length: 12" (300mm)
PTFE Magnetic Stir Bar Retriever, Length: 12" (300mm)
V&P Scientific Inc STIR ELEMENT, DISC, NdFeB Magnet, 42MGO, PVDF Encapsulated, Used in Microplates, Syringes, Tubes/Vials, 10/pack
STIR ELEMENT, DISC, NdFeB Magnet, 42MGO, PVDF Encapsulated, 8.0mm Diameter, 1.8mm Height, 150°C Max Operating Temp for Magnets
Cole-Parmer Mono-Mold Standard Stir Bar with Spinning Ring, 1-1/2"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.
Foxx Life Sciences Magnetic Stir Bar Mixer, 55mm Length, 8mm Diameter, Double Ended Dumbell Shape
257-1101-OEM: Magnetic Mixer, Double Ended, 8mm Diameter, 55mm Long. Foxx Life Sciences Magnetic Mixers are used to mix components in order to obtain a homogeneous liquid mixtures. Our mixers can be used in a variety of applications including but not limited to chemistry and biology experiments, buffer solutions, and bacterial growth media. Foxx magnetic mixers are ideal for mixing over a long period of time. Since our mixers are just magnet bars, they can easily be cleaned and the risks of contaminating the solution can be minimized.
Cole-Parmer Mono-Mold Standard Stir Bar, 3"L x 1/2" dia
Use this mono-mold standard stir bar with your large-capacity stirrers and hot plate stirrers.
Ace Glass, Inc. PTFE multi-paddle agitator, 38mm diameter
38mm diameter PTFE multi-paddle agitator for 10mm OD drilled or knob type shafts. Paddles are replaceable.
Ace Glass, Inc. Stirbars, PTFE, disposable, 25.4mmx8.0mm, pk/100
Stirbars, PTFE, disposable, 25.4mmx8.0mm, pk/100