PETG medium bottle  is a transparent plastic storage container used to store serum, medium, buffer and other solutions. In order to avoid microbial contamination caused by packaging, all of them are sterilized, and this packaging is mainly sterilized by cobalt 60.

Sterilization means to remove or kill all bacteria, viruses, fungi and other microorganisms on the PETG medium bottle by various physical and chemical means, so that it can reach the asepsis guarantee level of 10-6, that is, to ensure that the survival probability of microorganisms on an article is only one in a million. Only in this way can the microorganisms on the packaging be prevented from causing additional contamination of the internal contents.

Cobalt-60 sterilization is the use of 60Co γ-ray irradiation, acting on microorganisms, directly or indirectly destroy the nucleus of microorganisms, thereby killing microorganisms, play the role of disinfection and sterilization. It is a kind of irradiation sterilization technology. The γ-rays produced by the radioactive isotope cobalt-60 irradiate the packaged food. In the process of energy transmission and transfer, strong physical and biological effects are produced to achieve the purpose of killing insects, sterilizing bacteria and inhibiting physiological processes. 60Co-γ-ray irradiation sterilization is a “cold processing” technology, it is sterilization at room temperature, γ-ray high energy, strong penetration, in the sterilization at the same time, will not cause the increase in the temperature of items, also known as cold sterilization method.