This procedure is for cells in 96 well plates, if larger plates are used then adjust volumes accordingly.

1 Make a solution of 5mg/ml MTT dissolved in PBS and filter sterilise.

2. 5 hours before the end of the incubation add 20ml of MTT solution from step one to each well containing cells.

3. Incubate the plate at 37篊 for 5 hours.

4. Remove media with needle and syringe.

5. Add 200m l of DMSO to each well and pipette up and down to dissolve crystals.

6. Put plate into the 37篊 incubator for 5 minutes to dissolve air bubbles.

Transfer to plate reader and measure absorbance at 550nm.

Research @ Birmingham

Gene Therapy