There are many different kinds of stirrers available to be used in the laboratory. Each stirrer comes with a unique quality that makes it suitable for a specific application. Here are the different kinds of stirrers available and what they are used for.
Magnetic Stirrers
Magnetic stirrers employ a rotating magnetic field that causes a stirrer bar of a flea, which is submerged within a liquid, for spinning, and hence, stirring. Generally, magnetic stirrers are suitable for stirring small volumes of liquids with low viscosities. There are models, however, that have been designed to handle high viscosity and volume.
Magnetic stirrers usually have ceramic or stainless steel plates.
Stirrer Hotplates
Stirrer hotplates combine a stirrer and a hot plate. Both functions can be used independently or together.
There are many types of stirrer hotplates, but the main difference is the material used for the top plates:
Ceramic
The chemical resistance of ceramic top plates makes them ideal for use with corrosive chemicals that might splash onto the plate surface. Their higher temperatures can reach around 450°C and they are easy to clean.
Aluminum
In comparison with ceramic plates, aluminum top plates are more robust and are more resistant to accidental knocks.
Overhead Stirrers
An overhead stirrer comprises the stirrer, rods, paddles, and stands, and is generally more durable than a magnetic stirrer.
They are most commonly used for large volumes or viscous solutions.
A variety of paddles can create different stirring motions that are suitable for different applications:
- Paddle
- Centrifugal
- Turbine
- Dissolver
- Propeller
- Anchor
Specialty Stirrers
Submersible Stirrers
Submersible stirrers are sealed stirrers that are used for being submerged in water or oil, as well as being used at a wide range of temperatures. They are ideal for being used in water baths, ovens, incubators, etc.
Biological Stirrers
Biological stirrers are designed specifically to stir biological samples, like cell cultures. They offer gentle and heat-free stirring and are free from dust and germs.