Laboratory incubators are scientific equipment found in most research, analytical, or diagnostic laboratories. Lab incubators store collected samples or specimens in specified conditions so that the biological or chemical processes in the samples can take place in the desired conditions and with the least disturbance from uncontrollable influences.
Components in Laboratory Incubators
Lab incubators allow users to define and monitor the physical conditions inside the cabinet to suit the intended applications. They are used in several applications, for example, cell and tissue culture, protein crystallization, and chemical and biological assay testing.
On the most basic level, lab incubators consist of 
- An exterior made up of metals and insulation materials that houses a controller unit and an internal chamber;
- A controller unit between the exterior and interior chamber sealed in a box with a user’s interface that allows users to define and monitor the physical environment inside the internal chamber;
- An internal chamber where biological samples are kept, and the physical conditions of its interior are controlled and monitored. The chamber has metal shelves or holders where users can place and fix their samples.
Temperature Control in Lab Incubators
Temperature control is one of the important factors in biological and chemical reactions. Therefore, the way lab incubators achieve the desired temperature, speed and maintain it is essential in choosing the right lab incubators.
Lab incubators use electrical energy and convert it to thermal energy to achieve the predefined temperature and maintain it. They can reach the defined temperature by directly heating the surface of the chamber or to the air circulating the chamber.
In the second approach, thermal energy is generated in the space between the exterior and internal chamber before the heat is radiated to the air chamber. The space in-between can be filled with water or air, thus called water- or air-jacketed, respectively.
Low-temperature conditions are created using a vapor-compression system or a Peltier device
Refrigerated lab incubators use a vapor-compression system or a Peltier device to create and maintain the desired temperature lower than the lab incubator surroundings.
Lab incubators with a vapor-compression system compress and condense refrigerants into cool vapors that absorb the heat, lowering the chamber’s air temperature to as low as 4°C.
A Peltier device creates a cooling or heating effect at a junction where electrical energy is applied to two different materials, resulting in a range of temperatures that is to a certain degree lower or higher than the ambient temperature.
Types of Lab Incubators
Lab incubators are a class of climatic cabinets designed to accommodate and maintain a specific temperature range near the ambient temperature. Most standard incubators function optimally near 37°C, where most cells and animals thrive, and a few degrees above or below it.
Apart from temperature control, lab incubators often possess additional features that users can customize to create the most suitable physical conditions inside the chamber.
Some of the types are:
- A drying oven incubator is designed to accommodate extremely high temperatures and ambient temperatures. As a result, this incubator creates ambient conditions and functions as a drying oven.
- A CO2 incubator is a lab incubator with oxygen and carbon dioxide (CO2) monitoring and control features. These features allow users to control and monitor the humidity, oxygen level, and CO2 in the internal chamber.
- A shaker incubator is a lab incubator whose chamber surface is connected to motors. The motorized surface has sample holders where flasks with liquid samples can be swirled to distribute oxygen and nutrients evenly.
- An illuminated incubator is a type of lab incubator that supplies light to samples during incubation. It is often used with autotrophs such as cyanobacteria, green algae, and plant cells.
Choosing the Right Lab Incubator
Oftentimes, the right lab incubator is not the one with the most features or advanced technology. Instead, it’s the one that can simulate the desired conditions and maintain them with slight fluctuation so that no (or minor) artifacts are introduced to your work.
Here are the factors that you should consider before deciding on a lab incubator:
1. Lab Capacity and the Surrounding
The number of works and projects running in parallel is the first consideration in deciding on lab incubators’ capacities, features, and technologies. The following are what you should deliberate on:
● Size of lab incubators?
Large lab incubators consume more energy, increasing operation and maintenance costs. However, large incubators allow users to adjust the number of shelves and holders in the chamber, making the space fit users’ needs.
● Direct heat or indirect heat supply?
The internal chamber reaches the desired temperature faster when heat is directly applied to the surface. The direct heat approach requires a constant supply of power, which can be problematic in areas vulnerable to power shortages.
Thus, lab incubators with indirect heat supply are more suitable in such areas because they can preserve the temperature without power for a considerable period.[2,3]
● Water vs. air-jacketed lab incubators?
Air-jacketed lab incubators are typically cheaper and easier to set up and maintain, but unlike them, water-jacketed lab incubators sustain temperature longer and are more suitable for multi-user laboratories.
In addition, they take advantage of water’s high heat capacity, which can reduce the energy required to regain the desired temperature.
2. Intended or Most Frequent Applications
Having information on the desired applications can tell you the necessary and optional features in a lab incubator. Here are a few things to help guide you:
● Type of Lab Incubators?
Each type of lab incubator is designed to accommodate different applications. The suitable lab incubators are the ones that can create conditions most adapted to the applications.
On the contrary, standard incubators or shaker incubators are sufficient for most microbiological applications, although autotrophic bacteria will require some forms of illumination during the incubation period.[1,3,4]
● With or without humidity control?
Typically, ambient temperatures range from 60 to 90% in the incubator. If your work must be performed at a specified humidity level, choose lab incubators with a humidity control option. Otherwise, standard incubators with a transparent access door that seals the internal chamber are generally sufficient.
Most lab incubators can generate humidity by trapping water vapors inside the internal chamber, which can be achieved by placing a water-filled container.
However, lab incubators with a humidity control function typically have a water reservoir at the bottom chamber surface where water is heated or a vapor stream outlet that supplies a water spray to the chamber.
● Will microbial contamination be an issue?
Ambient to high humidity often leads to moisture condensation, which could be a source of microbial contamination. This is especially challenging for samples that need to be stored inside lab incubators for more than a few days.
If you are working with unique and limited samples sensitive to contamination, consider a lab incubator with an access door with a heating function or one made from electrically conductive materials to eliminate cold spots where water droplets form.
Alternatively, if your samples are replaceable, consider lab incubators with high-efficiency particulate air (HEPA) filters in the chamber or an option to connect an autoclave to their water stream generator. Similarly, you can also sterilize the water before filling the reservoir or placing it in the chamber to lower the chances of contamination.
● With or Without Fans?
Fans or blowers inside lab incubator chambers accelerate heat transfer. For example, our digital incubator can create temperature uniformity and reduce the number of cold spots in the chamber.
However, chambers with forced convection are drier, and the air inside the chamber is not stationary, which could disturb delicate processes such as egg hatchings and insect breeding.[1-2]
● Compressors or Peltier?
Peltier technology is regarded as the more environmental-friendly approach to refrigerated lab incubators, although it cannot achieve as low a temperature as the vapor-compression system. Suppose the intended applications require slightly lower temperatures than the ambient temperature, then lab incubators with Peltier technology are better than those with a vapor-compressor system.[2,3]
Lab incubators are used to collect samples and specimens in a user-defined condition. Specialized lab incubators allow users to control and monitor additional factors or create the most suitable conditions for their work.
Choosing the ideal lab incubator requires a comprehensive understanding of the lab setting and intended applications. Therefore, it is essential to factor in these elements in determining the necessary features and appropriate technologies in a lab incubator.
Check out our digital incubator if your lab requires a digital incubator for research, medical, and industrial applications.
- Hugh, Mark and Borton, Peter. Controlled Atmosphere Incubator. WO1997029616A1, World Intellectual Property Organization, 14 August 1997.
- Swain, Jason E. Decisions for the IVF Laboratory: Comparative Analysis of Embryo Culture Incubators. Reproductive BioMedicine Online, vol. 28, no. 5, May 2014, pp. 535–47, doi:10.1016/j.rbmo.2014.01.004.
- Butts, Charles G., and Runion, Timothy R. Ambient Temperature Stabilization Control System for Laboratory Incubator. US6177271B1, United States Patent and Trademarks Office, 23 January 2001.
- Pieczarek, Waldemar and Stahl, Hermann. Laboratory Incubator with Improved Interior Moistening. EP3578315B1, European Patent Office, 17 January 2015.