Hi Labrats, this might sound basic to some but can someone explain IC50 and what the general trends if in vitro drug exposure time is prolonged.

Experimental set-up:

1. Treatment Concentrations: 200uM, 175uM, 150uM, 125uM, 100uM, 75uM, 50uM, 25uM; Untreated; DMSO; Media only (no cells);
2. Treatment time: 30 mins; 2HRS; 3HRS;

What can I expect on the IC50-30 mins vs IC50-2HRS vs IC50-3HRs? Does it generally increase as you expose the cells longer to a drug?

Useful info: Drug is alpha-amanitin; cells are HCT116;

Thanks and I really appreciate it!

​

Edit: Our question relates to Transcription.. How well the drug can arrest transcription genome-wide while not inducing cell death.