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.
Bellco Glass, Inc. PTFE Stirring Bar,25.4mm
Molded, seamless Teflon construction ideal for procedures using all bellco magnetic stirrers. Excellent for mixing media and buffer solutions Size: 25.4 x 7.6mm Case qty: 6
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
Hach Company Stir Bar, Magnetic Egg-Shaped
Designed specifically for round bottom flasks and vessels. The PTFE coated, egg-shaped, magnetic stir bar fits the round bottom for uniform stirring without restriction. Recommended for the following round bottom flask sizes: 10, 25, 50, and 100 mL.
Chemglass Life Sciences Stir Bar, Magnetic, Glass, Length x Dia. in mm: 25.4 x 9.52, Length x Dia. in inches: 1 x 3/8
Stir Bar, Magnetic, Glass, Length x Dia. in mm: 25.4 x 9.52, Length x Dia. in inches: 1 x 3/8. Borosilicate covered Alnico magnet for use in high temperature reactions.
Chemglass Life Sciences Stir Bar, Magnetic, Triangular, PTFE, 20mm L X 8mm Diameter
Stir Bar, Magnetic, Triangular, PTFE, 20mm L X 8mm 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.
Chemglass Life Sciences Stir Bar, Magnetic, "X" Shaped, PTFE, 38 x 11: Diameter x Height (mm)
Stir Bar, Magnetic, "X" Shaped, PTFE, 38 x 11: 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.
GA International Permanent Deep-Freeze Labels for Thermal-Transfer Barcode Printers 1.625" x 0.625" / 41.3mm x 15.9mm Rectangle White From -80°C to +110°C (-112°F to +230°F)
Deep-freeze, permanent barcode labels for small diameter vials, microtubes, falcon tubes, cell culture plates, microplates, as well as polypropylene and cardboard freezer boxes. The freezer-grade labels are waterproof and tearproof, can adhere to moist and wet surfaces, and will permanently adhere to containers in (-20°C, -40°C, -80°C) freezers and dry ice without the need for extra lamination. Available in multiple configurations and colors, they are made of a durable thermoplastic film and will resist spraying with alcohols, bleach, detergents, surface cleaning wipes, and other chemicals.
Electron Microscopy Sciences Veco Parallel Bar w/ Divider Handle R200D, Nickel
Veco Grids offer superior handling characteristics. Plus, with a 0.8 mil thickness, Veco Grids are the most rigid grids available. 3.05 mm diameter and 0.8 mil thickness.
Material: Nickel
Pitch: 125 µm
Hole: 85 µm
Bar: 40 µm
Electron Microscopy Sciences Veco Parallel Bar with Divider R100Aspec, Nickel
Veco Grids offer superior handling characteristics. Plus, with a 0.8 mil thickness, Veco Grids are the most rigid grids available. 3.05 mm diameter.
Material: Nickel
Pitch: 250 µm
Hole: 200 µm
Bar: 50 µm
Electron Microscopy Sciences 24 Color Code Spin Bar Assortment Box
24 color coded octagon magnetic stirring bars: PTFE with pivot ring, consists of 1 each: Yellow, Red And Blue: 1/2"x1/8", 5/8"x 5/16", 7/8"x 5/16", 1/2"x 5/16", 1"x 5/16", 1.5"x 5/16", 2"x 5/16", 3"x1/2".