rblue1

Hello. I am conducting an experiment looking at secondary metabolite production though out the growth phase of a culture. I will need to take out fairly large volumes of culture over a period of 2-3 weeks to determine both microbial dry weights and metabolite concentration. In the past I have used a repeated measures design, i.e. repeated sampling from 4 large replicate flasks, never taking more than 10% of the original volume. However this most recent experiment using dry weights will require me to sample larger volumes and there is no way I can realistically use larger flasks. Instead I was planning on using many small flasks, and at each time point sacrificially sampling three flasks and taking the mean. Does this seem reasonable? If anyone can advice me on whether this is experimentally acceptable or knows of any literature that discusses such topics (it's a nightmare trying to search for this kind of stuff on web of knowledge!) I would be very grateful to hear from you. Thanks