Question: What is the most difficult experiment you have ever had to carry out?

Claire O'Connell answered on 12 Nov 2015:

The most difficult experiment wasn’t so difficult in theory as it was to actually carry out. It was a long experiment that took about 7 hours to do and I had 12 different samples. The challenge was not mixing up the samples along each step or mis-labelling them or adding in the wrong chemical in the wrong order. I was just glad when I made it through it without a mistake!