iGEMs InterLab study aims to establish a standard for developing a robust measurement protocol for GFP. GFP is chosen because it is one of the most used biological markers in synthetic biology laboratories.

Fluorescence data has been a poorly comparable measure since data is reported in various units or different groups process this data in different ways. That is one of the main reasons that fluorescence data is hard to share and compare between labs, which makes it harder to collaborate and troubleshoot.

Over the years, iGEM community has advanced in establishing a baseline for this protocol.
For the Fifth InterLab study, it is aimed to eliminate one more variable measure which is OD because OD measures yield high variability between labs and it is unclear how good an OD can approximate the number of cells.

Therefore, the Fifth InterLab study is asking if the lab to lab variability in fluorescence measurements can be reduced by normalizing to absolute cell count or CFUs instead of OD?