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, Triangular, PTFE, 25mm L X 14mm Diameter
Stir Bar, Magnetic, Triangular, PTFE, 25mm L X 14mm Diameter. Effective for dissolving solids and mixing sediments in a flat bottom container such as a beaker or erlenmeyer flask. Manufactured with FDA-grade and USP Class VI PTFE.
V&P Scientific Inc STIR ELEMENT, DISC, NdFeB Magnet, 48MGO, Parylene C Coated, Used in Syringes, Tubes/Vials, 10/pack
STIR ELEMENT, DISC, NdFeB Magnet, 48MGO, Parylene C Coated, 6.4mm Diameter, 0.7mm Height, 80°C Max Operating Temp for Magnets
Cowie Technology Corporation MICRO STIRBAR 3MM L 3MM D
This item has a minimum order quantity of 96 per supplier requirements. Stirbar, micro, length 3 mm, diameter 3 mm
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.
Cowie Technology Corporation DISC STIRBAR 20MM L 10MM D
This item has a minimum qty of 47 per supplier requirements.
Stirbar, disc, length 20 mm, diameter 10 mm
BIG SCIENCE INC STIR BAR CROSS 5/PK
Stir Bars Length 10 mm (3/8 in.) Height 5mm (1/5 in.) cross 5 pack
Cowie Technology Corporation TRIANGULAR STIRBAR L40MM D14MM
This item has a minimum qty of 37 per supplier requirements.
Stirbar, triangular, length 40 mm, diameter 14 mm
Cowie Technology Corporation MICRO STIRBAR 8MM L 1.5MM D
This item has a minimum order quantity of 132 per supplier requirements. Stirbar, micro, length 8 mm, diameter 1.5 mm
PATHOLOGY INNOVATIONS The 20mm Deep Well Bar has four 20mm wells, two that are 6mm deep and two that are 9mm deep, on one-inch thick stainless steel. These bars are stored in the cryostat and serve as a powerful heat sink to rapidly freeze the block.
When using the Peters Precision Cryoembedding System, embedding is performed in wells machined into the face of one-inch thick stainless steel bars offered in various sizes. The 20mm Deep Well Bar has four 20mm wells, two that are 6mm deep and two that are 9mm deep, on one-inch thick stainless steel. These bars are stored in the cryostat and serve as a powerful heat sink to rapidly freeze the block. Add additional well bars like this one to your existing Peters Precision Cryoembedding System. The Peters Precision Cryoembedding System was designed by inventor, professor and author of frozen section literature Dr. Stephen Peters to give users more precision and control when doing a high volume of frozen section procedures. Learn how to use the system as well as advanced frozen section technique at pathologyinnovations.com.