Complaint
An incubator is a device used to grow and maintain microbiological cultures or cell cultures. The incubator maintains optimal temperature, humidity and other conditions such as the CO2 and oxygen content of the atmosphere inside. Incubators are essential for much experimental work in cell biology, microbiology and molecular biology and are used to culture both bacterial and eukaryotic cells.
An incubator is made up of a chamber with a regulated temperature. Some incubators also regulate humidity, gas composition, or ventilation within that chamber.
The simplest incubators are insulated boxes with an adjustable heater, typically going up to 60 to 65 °C (140 to 150 °F), though some can go slightly higher (generally to no more than 100 °C). The most commonly used temperature both for bacteria such as the frequently used E. coli as well as for mammalian cells is approximately 37 °C (99 °F), as these organisms grow well under such conditions. For other organisms used in biological experiments, such as the budding yeast Saccharomyces cerevisiae, a growth temperature of 30 °C (86 °F) is optimal.
More elaborate incubators can also include the ability to lower the temperature (via refrigeration), or the ability to control humidity or CO2 levels. This is important in the cultivation of mammalian cells, where the relative humidity is typically >80% to prevent evaporation and a slightly acidic pH is achieved by maintaining a CO2 level of 5%.
| Model | APL-BJPX-80 | APL-BJPX-100 | APL-BJPX-150 | APL-BJPX-200 | APL-BJPX-250 | APL-BJPX-300 | APL-BJPX-400 |
| Capacity(L) | 80 | 100 | 150 | 200 | 250 | 300 | 400 |
| Temperature Control Range | 0~60ºC | ||||||
| Temperature Fluctuation | Heating: ±0.5ºC;Cooling: ±1ºC | ||||||
| Temperature Non uniformity Value | ±2ºC | ||||||
| Timing Range | 0~9999min/h | ||||||
| Rated Power(W) | 1000 | 1200 | 1400 | ||||
| Refrigerant | R134a | R404a | |||||
| Power Supply | Standard: 220V, 50/60Hz; Optional: 110V, 60Hz | ||||||
| Working Time | Continuous | ||||||
| Outer Size(mm) | 540*580*1100 | 540*580*1220 | 590*630*1380 | 590*660*1530 | 620*700*1600 | 660*700*1700 | 720*760*1800 |
| Chamber Size(mm) | 400*370*560 | 400*370*680 | 450*420*850 | 450*450*1000 | 480*490*1070 | 520*500*1170 | 580*540*1270 |
| Packing Size(mm) | 670*710*1270 | 670*710*1390 | 720*760*1550 | 720*790*1700 | 750*830*1770 | 790*830*1870 | 850*880*1970 |
| Gross Weight(kg) | 90 | 100 | 120 | 140 | 150 | 160 | 180 |
| Standard Accessories | Socket, Light | ||||||
| Optional Accessories | USB, Print | ||||||
| Remarks | * The performance parameter test is under no-load conditions, the ambient temperature is 20ºC; the ambient humidity is 50%RH * Cannot be used for long-term refrigeration storage | ||||||
A microbial incubator is made up of various units, some of which are:
Cabinet
The cabinet is the main body of the incubator consisting of a double-walled cuboidal enclosure with a capacity ranging from 20 to 800L.
The outer wall is made up of stainless steel sheets while the inner wall is made up of aluminum.
The space between the two walls is filled with glass wool to provide insulation to the incubator.
The insulation prevents heat loss and reduces electric consumption, thereby ensuring the smooth working of the device.
The inner wall of the incubator is provided with inward projections that support the shelves present inside the incubator.
Door
A door is present in all incubators to close the insulated cabinet.
The door also has insulation of its own. It is also provided with a glass that enables the visualization of the interior of the incubator during incubation without disturbing the interior environment.
A handle is present on the outside of the door to help with the maneuvering of the door.
Control Panel
On the outer wall of the incubator is a control panel with all the switches and indicators that allows the parameters of the incubator to be controlled.
The control panel also has a witch to control the thermostat of the device.
Thermostat
A thermostat is used to set the desired temperature of the incubator.
After the desired temperature is reached, the thermostat automatically maintains the incubator at that temperature until the temperature is changed again.
Perforated shelves
Bound to the inner wall are some perforated shelves onto which the plates with the culture media are placed.
The perforations on the shelves allow the movement of hot air throughout the inside of the incubator.
In some incubators, the shelves are removable, which allows the shelves to be cleaned properly.
Asbestos door gasket
The asbestos door gasket provides an almost airtight seal between the door and the cabinet.
This seal prevents the outside air from entering the cabinet and thus, creating an isolated hot environment inside the cabinet without being interrupted by the external environment.
L-shaped thermometer
A thermometer is placed on the top part of the outer wall of the incubator.
One end of the thermometer provided with gradations remains outside of the incubator so that temperature can be read easily.
The next end with the mercury bulb is protruded slightly into the chamber of the incubator.
HEPA filters
Some advanced incubators are also provided with HEPA filters to lower the possible contamination created due to airflow.
AN air-pump with filters creates a closed-loop system so that the air flowing inside the incubator generates less contamination.
Humidity and gas control
The CO2 incubators are provided with a reservoir underneath the chamber that contains water.
The water is vapourised to maintain the relative humidity inside the chamber.
Similarly, these incubators are also provided with gas chambers to give the desired concentration of CO2 inside the incubator.
On the basis of the presence of a particular parameter or the purpose of the incubator, incubators are divided into the following types:
Benchtop incubator
This is the most common type of incubator used in most of the laboratories.
These incubators are the basic types of incubators with temperature control and insulation.
CO2 incubator
CO2 incubators are the special kinds of incubators that are provided with automatic control of CO2 and humidity.
This type of incubator is used for the growth of the cultivation of different bacteria requiring 5-10% of CO2 concentration.
For humidity control, water is kept underneath the cabinet of the incubator.
Cooled incubator
For incubation at temperatures below the ambient, incubators are fitted with modified refrigeration systems with heating and cooling controls.
This type of incubator is called the cooling incubator.
In the cooling incubator, the heating and cooling controls should be appropriately balanced.
Shaker incubator
A thermostatically controlled shaker incubator is another piece of apparatus used to cultivate microorganisms.
Its advantage is that it provides a rapid and uniform transfer of heat to the culture vessel, and its agitation provides increased aeration, resulting in acceleration of growth.
This incubator, however, can only be used for broth or liquid culture media.
Portable incubator
Portable incubators are smaller in size and are used in fieldwork, e.g. environmental microbiology and water examination.
Principle/ Working of Incubator
An incubator is based on the principle that microorganisms require a particular set of parameters for their growth and development.
All incubators are based on the concept that when organisms are provided with the optimal condition of temperature, humidity, oxygen, and carbon dioxide levels, they grow and divide to form more organisms.
In an incubator, the thermostat maintains a constant temperature that can be read from the outside via the thermometer.
The temperature is maintained by utilizing the heating and no-heating cycles.
During the heating cycle, the thermostat heats the incubator, and during the no-heating period, the heating is stopped, and the incubator is cooled by radiating heat to the surrounding.
Insulation from the outside creates an isolated condition inside the cabinet, which allows the microbes to grow effectively.
Similarly, other parameters like humidity and airflow are also maintained through different mechanisms that create an environment similar to the natural environment of the organisms.
Similarly, they are provided with adjustments for maintaining the concentration of CO2 to balance the pH and humidity required for the growth of the organisms.
Variation of the incubator like a shaking incubator is also available, which allows for the continuous movement of the culture required for cell aeration and solubility studies.
Procedure for running an incubator
Once the cultures of organisms are created, the culture plates are to be placed inside an incubator at the desired temperature and required period of time. In most clinical laboratories, the usual temperature to be maintained is 35-37°C for bacteria.
The following are the steps to be followed while running an incubator:
Before using the incubator, it should be made sure that no remaining items are present in the incubator from the previous cycles. However, in some cases, if the same incubator is being used for multiple organisms, and they require the same set of parameters, they can be placed together in the same incubator.
The door of the incubator is then kept closed, and the incubator is switched on. The incubator has to be heated up to the desired temperature of the growth of the particular organism. The thermometer can be used to see if the temperature has reached.
In the meantime, if the organism requires a particular concentration of CO2 or a specific humidity, those parameters should also be set in the incubator.
Once all the parameters are met, the petri dish cultures are placed on the perforated shelves upside down, i.e., media uppermost. This is necessary because if the plates are incubated normally, condensation collects on the surface of the medium and prevents the formation of isolated colonies.
If it is necessary to incubate Petri dish cultures for several days, the plates are sealed with adhesive tapes or are placed in plastic bags or plastic food containers.
Now, the door is locked, and the plates are kept inside for the required time before taking them out.
