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.
Sigma Aldrich Fine Chemicals Biosciences CORNING MAG STIR BAR RETRIEVER
NC3848688 CORNING MAG STIR BAR RETRIEVER
Chemglass Life Sciences Chemglass Plain PTFE Magnetic Stir Bar, 80 x 10 mm
Plain PTFE magnetic stir bar for use with laboratory magnetic stir plates. The smooth cylindrical profile provides consistent mixing and helps reduce vortexing across a range of vessel sizes. The PTFE coating offers chemical resistance and easy cleaning, while the encapsulated magnetic core ensures reliable coupling to stir plates.
- Made from PTFE for broad chemical resistance.
- Plain cylindrical profile for consistent mixing.
- Encapsulated magnetic core for reliable coupling to stir plates.
- Dimensions: 80 x 10 mm (length x diameter).
- Sold individually (each).
- Suitable for routine laboratory stirring and agitation.
Sigma Aldrich Fine Chemicals Biosciences SpinbarR magnetic stir bar1EA
Leakproof seamless polished and contains a permanent Alnico V magnet. Egg-shape bar is designed especially for use in round-bottom vessels.
Chemglass Life Sciences Chemglass Stir Bar Retriever, PTFE, 350 x 10 mm (CG-2015T-03)
PTFE stir bar retriever designed to safely recover magnetic stir bars from reaction vessels and laboratory glassware. Molded in pure, FDA-approved PTFE for chemical inertness, the retriever is autoclavable and fitted with a strong magnetic tip for reliable pickup.
- Material: PTFE.
- Length: 350 mm.
- Diameter: 10 mm.
- Magnet options: Alnico V or rare earth.
- Autoclavable for laboratory sterilization.
- Designed for retrieval of magnetic stir bars from vessels.
Electron Microscopy Sciences Magnetic Stirring and Mixing Bars, 50.8 mm L, 8 mm diameter
These bars are designed for single use applications where efficiency and cross contamination is a concern. These economical bars have a "PTFE" coating which is chemically inert for high purity contact. The magnet is an Alnico V.
OAL: 50.8 mm
Diameter: 8 mm
Enterprise Technology Solutions Deflecto Mounting Bar, Storage Organizer, 22" L, Gray
Wall-Mounting Bar features an easy-to-use design to make installation fast and simple. Durable aluminum construction is capable of holding up to 40 lb. to keep your supplies in a convenient location. This 22" mounting bar is designed for use with Deflecto Stackable Caddy Organizer Canisters and Interlocking Single Tilt Bins (each not included) to store a variety of essential items in one place.
Electron Microscopy Sciences Stirring Rod PTFE with Steel Core, 350 mm, 6 mm diameter
Steel core can be bent into a permanent shape, rods are inert and will not scratch, use up to 280 degree C, rod OD: 6 mm.
OAL: 350 mm
Rod: 6 mm