2. Culture media

Over the past 50 years, the composition of culture media has evolved considerably. Whereas the very first media used only biological fluids, it very quickly became necessary to offer better-controlled formulations based on compounds essential for cell growth. There are two main categories of culture media, depending on whether or not they contain animal serums. The use of serum-free media is becoming the norm for most processes under development or recently introduced. On the other hand, some processes still use serum because of their long-standing validation, the use of more demanding cells, or the diagnostic use of the products generated.