When culturing various organisms it is vital that they do not become cross-contaminated compromising their viability.

Contamination is a major concern for any microbiologist. When culturing various organisms (bacteria, yeast, or fungi) for use in a multitude of downstream applications, it is vital that potentially contaminating microorganisms are removed from the incubation environment. If cultures do become infected with microorganisms, or cross contaminated with foreign cells, the viability of the culture is significantly compromised. In order to prevent this from having a negative impact on subsequent experimental steps and resulting data, contaminated cultures are commonly destroyed. As such, time and money are wasted as the entire preparation and culture must begin again, using fresh organisms and reagents. However, since sources of contamination are ubiquitous and difficult to identify, they are often especially hard to completely eliminate. As cell culture research is taking an increasingly prominent position in the development of therapeutics and vaccines, for example, it is vital that laboratories across the pharmaceutical, medical, food, research, and clinical sectors are employing incubation techniques with proven, trustworthy decontamination methodologies.

THE MICROBIOLOGICAL INCUBATOR
Designed for laboratory use, microbiological incubators maintain optimal conditions for the effective culture of prokaryotic and/or eukaryotic cells. They provide advanced control over temperature to ensure that organisms proliferate and grow in a fast and efficient manner. As incubators are commonly shared between multiple users, it is often the case that if the internal chamber is not properly cleaned, one user’s culture can have a negative effect on the next user’s culture, through the cross contamination of cell types. Furthermore, micro - organisms can be introduced through regular door openings, contact with skin/hair/ clothes, or poor cleaning routines. Bacteria and fungi (including yeast and molds) are the easiest contaminants to detect. They are also ubiquitous to the environment and can colonize extremely fast. Other contaminating microorganisms, such as mycoplasma and viruses, are more challenging to identify, yet can cause significant damage to the culture and, on occasion, the user. Therefore, the ideal microbiological incubator would incorporate an effective decontamination method, to ensure that even trace amounts of potentially detrimental contaminants are removed from the incubation environment. This ensures that precious cultures are protected and integrity is maintained.

Here, we discuss a third party test (performed by IBFE Institut fϋr Biotechnische Forschung und Entwicklung, Germany),¹ in which the 140ºC dry heat decontamination cycle of an incubator is tested for its effectiveness in eliminating a spectrum of contaminating microorganisms.