"passage number" is correct and usable in written English.
For example, you might say, "Please refer to passage number nine for more information."
The OECs were used at a passage number of 5 or less for the subsequent experiments.
Cells were not allowed to reach a passage number higher than 15.
The iNGN cell line5 at passage number 44 was a gift from George Church.
It is essential that the cells be well-maintained and of relatively low passage number.
In vitro migration assays indicated that MSCs at passage number 3 have the highest migrating ability.
Independent variables were the passage number of the cells and the plasmid loading.
Fibroblasts were used till passage number 20 and UT-SCC cell lines till passage number 55.
NPCs at passage number ≤15 were used in all experiments.
At the time of DNA extraction, HS293 was at passage number 47, and HS401 was at passage number 25.
At the time of DNA extraction, CH-ES1 was at passage number 19.
The passage number of any cell type never exceeds eight passages.
