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.
Ace Glass, Inc. Stirbar, PTFE, octagonal, yellow, 25.4mmx8.0mm
Stirbar, PTFE, octagonal, yellow, 25.4mmx8.0mm
Electron Microscopy Sciences Stirring Rod PTFE with Steel Core, 400 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: 400 mm
Rod: 6 mm
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
Cole-Parmer Micro Stir Bar, 10mm L x 3mm dia 10mm L x 3mm dia.
Strong alnico V magnets with one-piece coating of PTFE.
Hach Company Stir Bar 17.2 mm x 10.5 mm - Replacement for 5500sc Analyzers
Replacement stir bar for use with 5500sc analyzers. The bar's compact dimensions match the analyzer sample chamber to provide reliable agitation and consistent mixing for routine analysis.
- Dimensions: 17.2 mm x 10.5 mm.
- Designed to provide consistent mixing in small sample chambers.
- Sold as a spare part for laboratory analyzers.
- Safety Data Sheet (SDS) available from the manufacturer.
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.
HTDialysis LLC HTD Universal Stainless Steel Connecting Rods
HTD Universal Stainless Steel Connecting Rods. Replacement part for HTD reusable micro equilibrium dialysis or buffer exchange desalting devices. The HTD devices were developed at a Global Pharmaceutical Research Laboratory with and combine industry-leading accuracy and precision with an automation compatible design for a scalable, cost-efficient, and eco-friendly solutionFor use with:HTD96B – equilibrium dialysis device HTD96C – equilibrium dialysis deviceHTD12A – buffer exchange and desalting device
Chemglass Life Sciences Stir Bar, Micro, Magnetic, PTFE, Length x Dia. in mm: 2 x 2, Bulk Packed
Stir Bar, Micro, Magnetic, PTFE, Length x Dia. in mm: 2 x 2, Bulk Packed. Micro PTFE stir bar for the very smallest containers. Manufactured with FDA-grade and USP Class VI PTFE.
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.
Bellco Glass, Inc. PTFE Stirring Bar,50.8mm
Molded, seamless Teflon construction ideal for procedures using all bellco magnetic stirrers. Excellent for mixing media and buffer solutions. Size: 50.8 x 9.5mm Case qty: 6