Encapsulated Magnetic Stir Bars and Discs

Encapsulated PTFE Magnetic Stir Bars

Neodymium Iron Boron (NdFeB) is the strongest (52 MGO) of the permanent magnetic materials. Previously, Neodymium Iron Boron has not been available as a completely encapsulated Magnetic Stir Element. V&P is the only source of encapsulated NdFeB. We offer a high (52 MGO) and a low (42 MGO) strength magnet. The low strength (42 MGO) magnets are more temperature resistant (150°C) and can be autoclaved for sterility purposes while the high strength (52 MGO) magnets are inactivated at 80°C. So you need to select your magnets with your application requirments in mind. We also offer Samarium Cobalt (SmCo – 29MGO) rare earth magnets which are available for even higher-temperature (300°C) applications. By way of comparison, Alnico magnets the most commonly used in magnetic stir bars, are much weaker at only 7 MGO. So if you need to stir viscous material, yeast starter cultures, slurries, soil samples, wood chips or particulates at high speeds, this is the system for you.

The disc design of the VP 772D series makes them significantly more efficient at moving liquid and thereby mixing solution in the tumble mode. Selecting a disc that is slightly smaller than the inside diameter of the vessel to be stirred results in the most efficient stirring. To stir viscous material requires greater energy so we constructed these discs from Neodymium Iron Boron and encapsulated them with PTFE to make them inert.

The VP 772DP-N42-5-2 and VP 772DK-N42-5-2 (5 mm diameter x 1.7 mm thick) PTFE and PEEK encapsulated disc was designed to fit into 96 well microplates, deep well 96 well microplates and glass micro-tubes.

The VP 772DP-N42-8-2 (8 mm diameter x 1.8 mm thick) PTFE encapsulated disc was designed to fit into many vials. If your application requires a different diameter, let us know.

If your application entails grinding to make nano particles you may also want to use our abrasive resistant PEEK encapsulated NdFeB or SmCo.

The VP 772BP series are encapsulated PTFE Magnetic Stir Bars.  These stir bars either contain NdFeB (42 MGO), NdFeB (52 MGO), or SmCo (MGO) Magnets and come in a wide variety of lengths.

• NdFeB (42 MGO) magnets have a max 150°C operating temperature.

• NdFeB (52 MGO) magnets have a max 80°C operating temperature.

• SmCo (29 MGO) magnets have a max 300°C operating temperature.

These stir bars provide strong mixing when combined with our VP 706B-3 Mini Stirrus or our heated Mini-Strrus VP 706B-4H.

NdFeB (42 MGO) Magnet- Temperature resistant to 150°C

NdFeB (52 MGO) Magnet - Temperature resistant to 80 C

SmCo (29 MGO) Magnet - Tempature resistant to 300 C

Download Video of Encapsulated Magnetic Stir Bars  
(mpeg movie- 10MB)

Press the play button to view the video in a flash format, flash must be installed, or click the download link to download a mpeg version.