What Is Magnetic Stirrer
A magnetic stirrer is an instrument is used for creating a rotating magnetic field. It is made with a small bar magnet and a stand or plate containing a rotating magnet.
The bar magnet is basically coated with plastic whereas, plate contains a rotating magnet. The rotating magnet is chargeable for making a rotating magnetic field. The rotating magnet creates a rotating field or sets the motionless electromagnets put under the vessel with the fluid. If you have never worked with a magnetic stirrer you simply don’t know where to start. This is why I am writing this blog post on magnetic stirrer buying guide to help you with your search and purchase.
The stirrer is famous in biology and chemistry labs. These are used in hermetically closed systems or containers. Magnetic stirrer can perform all relevant tasks while taking care of important matters and pressings. The stirrer consists of a small bar magnet and stands with the rotating magnet. The magnet bar is covered with plastic, and this special setup is useful to create a magnetic field.
You can use magnetic stirrer in numerous industries for different applications. It is used to mix or stir samples of fluid. The stirrer is really useful in the chemical and food industry. Moreover, it has numerous uses in the biotechnology industry.
How Magnetic Stirrer Works
The bar magnet is placed in a vessel which contains a liquid which is to need to be stirred. At the top of the stand, the vessel is set where the rapidly rotating magnetic field causes the bar magnet to rotate, which results in the stirring of the liquid. The small size of magnetic stirrer is the reason for widespread use in laboratory experiments.
Use Of Magnetic Stirrer
The stirrer aka magnetic plates is useful in different firms. People often conduct biological and chemical experiments with the use of a magnetic stirrer If you want to mix two components together, the magnetic stirrer can be really helpful for you. It is equally good for solids or liquid samples to obtain a consistent liquid mixture. For instance, media for bacterial growth is a special sample for a magnetic stirrer.
Ways To Use Magnetic Stirrer
The special magnetic field of magnetic stirrer can mix the solution in a better way. Just put the sample in the stirrer and start stirrer. As it starts spinning with its small bar magnet, it will create an exterior magnetic field. It is a small device and easy to use in your laboratory. Moreover, you can carry it from one place to another, but make sure to follow all safety precautions before moving this stirrer from one location to another.
Types Of Magnetic Stirrer
(Based on the size, configuration, and applications)
- Magnetic Mini Stirrer
Mini magnetic stirrers is a compact size stirrer that occupies less space and consist of electronic controls that allow the user to regulate the speed with greater precision. It is resistive to harmful chemicals in the lab. The speed regulator in the instrument controls the maximum speed.
- Magnetic Stirrer with Timer
Magnetic stirrer with timer helps to automatically shut off the motor after the selected amount of time. An in-built timer will shut the stirrer off once the pre-selected period of time has passed. The speed is get reduced automatically and even the load is automatically removed.
- Heavy-Duty Magnetic Stirrers
The heavy-duty magnetic stirrer comes with good chemical resistance, highly durable and also have high mixing capacity. They can be the best choice instrument for laboratory use as well as use in production. There is an in-built electronic management device that regulates the speed automatically with respect to load.
- Battery Powered Magnetic Stirrer
They can be used where there are no electric outlets. They are primarily used in incubators and consist of rubber feet, speed control knob, etc. The batteries used for their operation work are either alkaline batteries or rechargeable type batteries.
- Air Operated Turbine Magnetic Stirrer
Air operated turbine magnetic stirrer is an ideal instrument for stirring liquid up to 1 liter. The stirrer uses low-pressure air supply to power this magnetic stirrer. The important aspect of that magnetic stirrer is that it eliminates the sparking hazard from electrical sources.
Benefits Of Magnetic Stirrers
The magnetic stirrers are important to reduce the risk of contagion. Only one magnetic bar will be in the sample, and it is easy to keep your device clean. A magnetic stirrer is entirely different than the manual one. If you want to reproduce a mixture for a long time, you are in need of a magnetic stirrer. For instance, if you want to carry on the procedure of protein dialysis, you have to perform this process on one sample, and this sample will be placed on the magnetic stirrer for a longer period. Various laboratories choose an overnight mixing process to utilize their valuable time in a better way. It is possible only with the help of a magnetic stirrer instead of a manual stirrer.
What You Need To Look Before You Make Purchase Of Magnetic Stirrer
Magnetic stirrers are one of those handy dandy instruments that we use every day in our lab. You can certainly survive without them (as most of you already have) but having (at least) one of them makes your life in the lab much easier.
If you start searching for magnetic stirrers, the diversity of models and prices are so vast that you’ll be overwhelmed in the first 10 minutes. Prices vary between model to model and with specifications if you have never worked with a magnetic stirrer you simply don’t know where to start. This is why I am writing this blog post to help you with your search and purchase.
Function and Features
First and foremost, you must know what is required of the unit. Before beginning your search for an adequate unit, make a list of the most common jobs the magnetic stirrer will be doing. What volume samples will you be stirring? Is it necessary to also heat the sample as it is being stirred? Then need to buy stirrer with a hot plate. What size vessels will you be using the most? Write it all down in a summary that you’ll use while shopping. A list may look something like this:
Sample range(rpm): 800(rpm)
Temperature range: RT-250°C
Max stirring capacity: 2ltr
Heating Capacity: 350 wattage
You need to consider the scale of your work. Traditional magnetic stirrers heat and stir a single sample at a time. However, there are units available today that can handle multiple vessels at once. If you are mixing in large volume, it might very well be worth it to consider acquiring a multi-position unit. Otherwise, single-position hotplate stirrer is good for you like our stirrer.
At this point, you might also decide whether or not certain features will increase efficiency and if the additional cost is worth it. Will a digital readout make more sense than an analog control? Is a temperature sensor necessary to monitor consistent temperatures? Will you be logging data via a laptop or computer? All of these options are available from most manufacturers as an add-on or are integrated into the magnetic hotplate stirrer.
Maintenance And Warranty
Before making a purchase of magnetic stirrer you need to think about Maintenance and warranty of your product. If you plan on holding onto the same unit for a long period of time, you might want to search for one that has a strong warranty and a low cost-of-use. Warranties are pretty standard across the board but it is the cost of service and maintenance that is something you’ll want to consider once the warranty has run out.
The Budget For Choosing Magnetic Stirrer
Budget Cost is always a guiding factor when purchasing lab equipment. Typically speaking, the budget is one of the first considerations before making a buying decision. However, I would caution against that line of thinking. If you have already ready to purchase a magnetic stirrer, it should be more important that you get a unit that will do everything you need it to do regardless of price. Purchasing anything only based on price rarely yields the satisfaction and efficiency that you would hope for.
There are simple magnetic stirrers without any hot plate and magnetic stirrers with a hot plate. The price of a magnetic stirrer with a hot plate is much higher than the price of a magnetic stirrer.
Max. Permissible Temperature And Humidity
If you work in a humid lab and your lab is located in tropical regions, or you intend to blend hot material, have a look at the max. allowed working temperature and humidity of the instrument before you purchase yours.
Mounting Surface Dimensions
The surface dimension obviously defines the size of the beakers you can use with each magnetic stirrer. Your beaker could have a max. diameter as the plate. In some technical data, even the max. allowed dimensions of the stirring rod are mentioned.
Obviously, a magnetic stirrer needs a magnet to operate. Magnets are available in all possible sizes and forms, from simple rods to starts, ellipsoids, discs etc. I would recommend that you start with a simple rod at the beginning. You can do nothing wrong with a rod. The size of the stirring rod should be suitable for your beaker.
When purchasing a magnetic stirrer with a hot plate, you obviously need to consider:
- The heat output (power/Watt of the hot plate)
- Heating range (you shall rather have a look at the minimum heating temperature because the max. temperature is much higher than what you’ll need)
- Min. and max. adjustable temperature
What Can Magnetic Stirrer do and can’t do
Before you become euphoric and promise to have a one-for-all-purpose tool in your lab let us make clear what a magnetic stirrer can do or can not do. A magnetic stirrer is, well a stirrer so you can’t expect it to be a homogenizer. It works excellent for blending low to medium viscosity liquids and gels but it does not replace a homogenizer.
Although you can disperse low concentrations of gum with a magnetic stirrer, it is not the best choice for gum dispersion and we never use ours for this purpose. They are excellent for blending surfactants, blending oil and water phases and for all procedures when you need a long and uniform blending without much agitation.
Making an oil blend
Making a surfactant blend
Blending the oil and water phases of an emulsion
Slowly adding one phase to the other (such as making a W/O emulsion with Symbiomuls WO) Slowly adding the surfactant phase to the water phase under gentle stirring to avoid foam Blending the EO-solubilizer phase and the water phase separately (when making a tonic or body splash) and then blending the two phases
I think I have covered all the important features you need to know before purchasing a magnetic stirrer. It is really worth considering how often you’ll need a magnetic stirrer hot plate before you indulge yourself with an instrument. This is something only you can decide, knowing your requirements, your daily procedure and the necessities in your lab.
If you seldom both heat and stir, then you shall probably consider having a simple magnetic stirrer and a separate hot plate. If you have very little space and use both procedures simultaneously, then you shall think about investing more in a combination instrument. At AntsLab we offer Hotplate Magnetic Stirrer, Hydrothermal Bomb, and many more laboratory products you can go to our AntsLab website to know more about our products.