Laboratory shakers: what they are, types and how to choose
— Equipo JP Selecta
Most protocols require a sample to be mixed at some point, but doing it by hand introduces variations that are difficult to measure: the time, intensity, aeration and even the pattern of movement change.
Choosing a laboratory shaker makes it possible to turn that task into a controlled, repeatable and documentable process. The right choice is driven not by maximum speed but by what the sample physically needs.
Suitable equipment prevents concentration gradients, unwanted sedimentation or excessive foaming. It also helps to reproduce the result across operators, shifts or batches. That is why, before comparing models, it is worth defining the container, the volume, the viscosity, the sensitivity of the sample and whether the protocol includes temperature control.
What is a laboratory shaker and what is it used for?
A laboratory shaker is a device that applies a defined movement to a sample in order to mix, dissolve, suspend, homogenise or promote mass transfer.
A laboratory shaker is used to keep a solution uniform, improve contact between reagents, supply oxygen to certain suspension cultures or speed up a reaction step without depending on the operator's manual effort.
The key is control. Insufficient agitation leaves areas with different concentrations or without the necessary oxygenation; excessive agitation can generate foam, splashes or shear that is harmful to cells and macromolecules. Speed, orbit, drive type and time must be adjusted to the method, not chosen in isolation.
The 6 main types of laboratory stirrers and shakers
The types of laboratory shaker are distinguished by the movement they transmit to the sample. That movement determines the mixing intensity, the exchange with the air, the behaviour of particles and the mechanical stress applied.
Choosing the wrong one can prevent the homogenisation sought or alter a delicate sample.
Heated magnetic stirrer
The magnetic stirrer generates a rotating field that spins a magnetic stir bar inside the container, with no mechanical shaft in contact with the liquid. It is an efficient option for solutions, reactions and the preparation of low- or medium-viscosity media. When heating is required while mixing, the hotplate makes it possible to control both variables at a single workstation.
In the Agimatic range, the stirrers can handle up to 10 L and the heated models reach 350 °C. The ceramic surface of versions such as the Agimatic-ED-C is particularly useful when chemical resistance and uniform heat distribution are required; to control the actual temperature of the fluid, a compatible probe should be used rather than inferring it from the plate temperature.
→ You may be interested in our catalogue of hotplates.
Orbital shaker
The orbital shaker moves the platform along a horizontal circular path. This movement is appropriate for flasks, bottles, plates and cultures when uniform mixing and moderate aeration are needed. In cell or microbial cultures, agitation that is too intense can increase shear; agitation that is too gentle can limit oxygen exchange.
Speed (rpm) alone does not define the result: the combination of speed and orbit diameter determines the acceleration the liquid receives. A larger orbit can help move larger volumes at moderate speeds, while a smaller orbit at higher speed is better suited to plates or small tubes. For this reason, both parameters and the container clamping system should always be compared.
Reciprocating shaker (linear)
The reciprocating shaker moves the platform from side to side. Its mixing is gentler than that of a vortex mixer and can be suitable for containers, racks, separating funnels or samples that need continuous movement without intense turbulence. Multi-purpose systems make it possible to select orbital or linear movement depending on the assay.
The platform and adapters are part of the choice: a clamp that does not hold a flask or rack correctly alters the mixing and compromises safety. The Rotabit and Rotaterm shakers offer both movements with adjustable speed; the Rotabit accepts interchangeable platforms to adapt to the working format and the Rotaterm incorporates a hotplate.
You can see our orbital and reciprocating shakers in our catalogue.
Vortex mixer
The vortex mixer transmits vibration to the container through a rubber head and creates an intense swirl in seconds. It is designed to resuspend a pellet, mix an individual tube or rapidly disperse a reagent, not to keep flasks agitated for hours. The choice between touch activation and continuous operation depends on whether the work is occasional or done in batches.
Models with speed control make it possible to move from gentle to intense mixing without changing instrument. The Vortex-Vib works at a constant 2,800 rpm, in touch or continuous mode, and its interchangeable platforms adapt it to the size and number of samples processed.
Orbital shaker with incubation or refrigeration
An orbital shaker with incubation combines platform movement with a controlled thermal environment. It is suitable for bacterial, yeast or cell cultures when the protocol requires a defined temperature to be maintained for several hours. Refrigerated models make it possible to work below room temperature or to offset the heat produced by the motor and the activity of the sample.
An orbital incubator usually integrates digital control of speed, temperature and time, together with alarms and a door-open safety cut-out. For prolonged use, priority should be given to a brushless or induction motor, and the thermal uniformity, the platform capacity and the compatibility with the protocol's flasks or microplates should be verified. In our catalogue, the TRM-4 thermoshaker heats and shakes up to 4 96-well microplates, and the Boxcult incubation chamber can house orbital or reciprocating shakers inside.
Rotary agitator
Rotary agitators mix samples by rotating the container or a holder that contains it. The rotational movement promotes homogenisation and is useful in applications where samples need to be kept moving continuously and in a controlled manner. Their specific application depends on the design of the device, the rotation speed and the type of container used.
Depending on the model, they can be used to mix tubes, bottles or other containers, especially when gentle, constant agitation is required.
Among our rotary agitators, the Orbit-II offers adjustable speed to adapt to the requirements of your samples.
Choose the laboratory shaker you need
| Type | Movement | Typical use | Key criterion |
|---|---|---|---|
| Magnetic | Rotation of a magnetic stir bar | Solutions and reactions | Volume, viscosity and need for heat |
| Orbital | Horizontal circular orbit | Flasks, plates and cultures | Orbit, rpm and aeration |
| Reciprocating | Linear movement | Racks and gentle mixing | Container and clamping system |
| Vortex | Localised vibration | Individual tubes | Intensity and occasional or continuous work |
| Incubated orbital | Orbit with thermal control | Prolonged cultures | Temperature, platform and continuity |
| Rotary | Rotation of the container or its holder | Continuous mixing of tubes or containers, depending on the model | Speed, orientation and capacity |
How do you choose the right shaker for your laboratory?
To choose the right shaker, it is worth answering three questions before comparing instruments.
This sequence avoids investing in a model that works correctly but does not suit the container, the method or the actual duration of the work.
What type of container do you use and what volume do you handle?
The container format is the first filter: a tube, an Erlenmeyer flask, a microplate or a separating funnel are not held or moved in the same way.
The working volume and the total platform load also matter. A universal platform with interchangeable clamps provides versatility on an orbital shaker; a reciprocating solution may be more appropriate if the protocol calls for gentle linear movement.
Does your protocol require controlled temperature?
The equipment depends on the protocol:
- A bacterial or yeast culture usually requires an incubated shaker.
- Heat-sensitive proteins may need refrigeration equipment in addition to a shaker.
- A chemical synthesis or a dissolution step may require a heated magnetic stirrer.
The set-point temperature is not necessarily the same as the sample temperature: where this is critical, it must be verified with a probe and an appropriate control procedure.
Will the motor run continuously?
For cultures of 12 to 48 hours or repetitive tasks, the robustness of the drive and overload protection are operational criteria.
Brushless or induction motors reduce maintenance requirements and are suitable for continuous operation.
In addition, the timer, alarms and restart after an interruption can be decisive in processes that are not constantly supervised.
At J.P. Selecta we bring together magnetic stirrers and orbital, reciprocating, vortex and rotary shakers to cover everything from occasional mixing in a tube to prolonged agitation of flasks or microplates with thermal control. Selecting the right family based on the movement, the container and the conditions of the method makes it possible to obtain reproducible mixing and safer operation, with the technical support needed to configure the equipment and its accessories.