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, Magnetic, PTFE, Turbo, Rare Earth, Elliptical, 70 x 28mm
Exceptional strength coupled with almost total resistance to demagnetisation. Identified by an inert carbon black spot.
BIG SCIENCE INC GIANT PLAIN STIR BAR 6IN 1IN D
Giant Plain Stir bar: Length 159 mm (6 inches), Diameter 27 mm (1 inch)
Sigma Aldrich Fine Chemicals Biosciences Rare earth extra power stir bars, 3/pk
Elliptical, diam. 6 mm, L 10 mm. Stirring bars using rare earth magnets have significantly increased magnetic strength compared to those using Alnico magnets, but more importantly they are almost totally resistant to demagnetisation.
Sanisure Inc Gamma Stable Stir Bars
The SaniSure Gamma Stable Stir Bars are the ideal product for simple agitation of biopharmaceutical process solutions. Available standalone or integrated into a variety of container formats, they provide a simple mixing solution and process flexibility. SaniSure Gamma Stable Stir Bars are available in various sizes to suit the desired container volume. They are Animal Derived Components Free, meet USP Class VI, and are lot traceable.
Ace Glass, Inc. Stirbar, PTFE, egg shape, 25.4mmx12.7mm
25.4mm x 12.7mm egg-shaped PTFE magnetic stir bar which provides a pivot point without a separate ring or abrupt change in contour. Designed to be used with round bottom flasks and DynaBlocs.
V&P Scientific Inc STIR ELEMENT, CYLINDER, Stainless Steel, Parylene C Coated, Used in Microplates, Tubes/Vials, 1000/pack
STIR ELEMENT, CYLINDER, Stainless Steel, Parylene C Coated, 2.0mm Diameter, 4.8mm Length, 200°C Max Operating Temp for Coating, Used for Parallel Synthesis/Reaction Optimization, (1000/Pack)
Ace Glass, Inc. Stirbar, PTFE, octagonal, 28.6mmx8.0mm
28.6mm X 8.0mm PTFE, octagonal stirbar with pivot ring in center.
Sigma Aldrich Fine Chemicals Biosciences CORNING MAG STIR BAR RETRIEVER
NC3848688 CORNING MAG STIR BAR RETRIEVER
Chemglass Life Sciences Stir Bar Kit, Magnetic, PTFE
Stir Bar Kit, Magnetic, PTFE. Stir Bar Kit containing octagon cross-section shaped magnetic stir bars having a molded-in pivot ring manufactured with FDA-grade and USP Class VI PTFE. The PTFE coated Alnico magnet permits magnetic agitation without contamination.To Consist Of The Following: 6ea CG-2001-01, 6ea CG-2001-02, 2ea CG-2001-04, 3ea CG-2001-09, 1ea CG-2001-08, 1ea CG-2001-13, 1ea CG-2001-17
Chemglass Life Sciences Stir Bar, Magnetic, "X" Shaped, PTFE, 60 x 20: Diameter x Height (mm)
Stir Bar, Magnetic, "X" Shaped, PTFE, 60 x 20: Diameter x Height (mm). Shape of stir bar creates a deep vortex and provides stability during stirring. Manufactured with FDA-grade and USP Class VI PTFE.
Chemglass Life Sciences Stir Bar, Magnetic, "X" Shaped, PTFE, 20 x 8: Diameter x Height (mm)
Stir Bar, Magnetic, "X" Shaped, PTFE, 20 x 8: Diameter x Height (mm). Shape of stir bar creates a deep vortex and provides stability during stirring. Manufactured with FDA-grade and USP Class VI PTFE.
Chemglass Life Sciences Agitator, PTFE, High Viscosity, 7.5in Diameter, Fits 19mm Shaft Size, Fits 10L-15L Reactors
Agitator, PTFE, High Viscosity, 7.55in Diameter, Fits 19mm Shaft Size, Fits 10L-15L Reactors. High viscosity agitator, made entirely of PTFE and glass filled PTFE, provides excellent stirring at the bottom of 10L through 15L reactors, especially when heavy slurries are being mixed. Agitator attaches to stir shaft by both a compression fitting and a glass filled PTFE safety pin. Heavy duty blades are 7mm thick. Supplied complete with one glass filled PTFE safety pin.
Chemglass Life Sciences Stir Bar, Magnetic, "X" Shaped, PTFE, 30 x 10: Diameter x Height (mm)
Stir Bar, Magnetic, "X" Shaped, PTFE, 30 x 10: Diameter x Height (mm). Shape of stir bar creates a deep vortex and provides stability during stirring. Manufactured with FDA-grade and USP Class VI PTFE.