Keeping it warm with CO2 Incubators

Temperature Monitoring is not always about keeping materials cool, it can also be about keeping materials warm.

Experiments that replicate the process of living organisms are called in vitro.  Cells and tissue cultures are grown in a laboratory over time in an environment that is as natural as possible.  Cultivation takes place in a CO2 incubator where the temperature, humidity, and carbon dioxide content must be controlled.  The oxygen and nitrogen content can also be adjusted in some appliances.

The CO2 incubator usually has a chamber volume of between 13.2 and 80 gallons and a temperature range from 40°F and 46°F above room temperature to 140°F.  The interiors of CO2 incubators are normally made of corrosion-free stainless steel.  They are additionally smoothed with electrolytic polishing by some manufacturers to prevent germs from settling and to make cleaning easier.  To observe the chamber load without affecting the atmosphere inside the chamber, CO2 incubators are usually equipped with an inner glass door or additional gas baffle.

When regulating air humidity the normal temperatures in a CO2 incubator lie at or around the same temperature as the human body (98.6 °F).  The essential matter in this is0 maintaining humidity in a controlled manner, while at the same time avoiding condensation in the interior.  This is done in practice either through humidification via water trays in the interior of the CO2 incubator or via direct contact of water with the floor or through an activity controllable system for humidification and dehumidification in which the water supply lies outside the working chamber.  The water from the external water tank is heated up in a vaporator and fed into the chamber as steam this being the only sterile water (pyrolytic germ barrier) humidifies the chamber and the samples and the humidity can be applied in specific doses.

When heating the chamber, it must be precisely maintaining.   The atmosphere is essential in a CO2 incubator to protect the samples.  Therefore, there is a whole range of different heating systems in practice that is supported in part by motorized fans, and in part by air circulation systems free of turbulence.

CO2 incubators are supported by a heated air jacket, and in some cases by a water jacket, ensuring even temperature distribution.  With a water jacket for temperature stability a rapid recovery times after the door has been opened and maintenance of the temperature after a power failure is essential.  At the same time, the air jacket prevents condensation from forming.  Some manufacturers, who do without a jacket of air or water, instead of heating the chamber directly from all six sides, surrounding it in additional insulating coat.  In this form of direct heating, a high degree of flexibility and a high density in the arrangement of heating elements form the basis of temperature homogeneity.

Sterilization and decontamination are important for success and prior to each new load, a CO2 incubator must be cleaned to avoid cross-contamination of the chamber load. In addition to cleaning with disinfection agents, appliance manufacturers have developed various technologies, some of which can be combined.  Some appliances allow sterilization of the interior with UV light, others provide permanent air filtering.  Air filters such as HEPA filters require additional resources of time and money since they need to be replaced.

Some manufacturers provide a decontamination routine using damp heat at 194 to 202 °F, and which takes many hours, others decontaminate for several hours at 248°F.  Hot-air sterilization between 320°F and 356°F is quite common and recognized as a safe procedure.  The German pharmacopeia 10 (DAB 10), a collection of recognized pharmaceutical rules concerning quality, testing, storage, dispensing and labeling of drugs and the substances of legally binding character that are used in their production, stipulates the following reference values for the duration of sterilization, Hot air at 356 °C for at least 30 minutes, Hot air at 338 °F for at least 1-hour, Hot air at 320 °C for at least 2 hours.  A further quality criterion for modern CO2 incubators is the option of decontaminating or sterilizing the interior, including fittings and sensors.

Temperature monitering is essential to succesful operation of running Experiments in CO2 incubators and need comprehsive temperature monitering by a trusted Temperature Monitering Company.