Using regular flasks, cells should be subcultured as soon as possible when they reach a confluent monolayer state or saturate the carriers.
With Petaka, grown cell cultures can be maintained alive at room temperature, without dehydration risk, for long time periods.This facilitates cell culture management and maintenance routines; and provides additional advantages for cell biology and toxicology research (see "Petaka Quick Protocols" for conditions and methods, such as protocols 4 and 8 - "Keeping Cells in In-Vitro Dormancy").
Cell conservation in dormant state is favored by transferring cultures from 37° C to 22° C when cells are in a slow progressing cell cycle. This is achieved in an 80% confluent state.
Under low temperature and low pH, cells reduce DNA replication practically to zero, and remain in a suspended animation-like state (a certain accumulation of cells in G2 phase could be expected).The duration of the dormancy period is dependent on the cell type. At a minimum, 7 days survival is common for most cells, while others could live for more than 200 days.