It depends on what experiment you are doing. Often the longest part is getting ready for the experiment which can take several days.
The reaction I use that copies DNA takes about 4 hours. It takes me 30mins to get everything together, 4 hours to copy the DNA and then a couple of hours to examine some of the genes in the DNA by a technique called PCR.
But before I do that I have to grow my cells, break them open and get the DNA out.
Hopefully if I manage to complete my device this will shorten the process and at the very least I won’t have to do all of it, I’ll just give the device my cells and press go then come back later to collect the DNA.
Now, if I could only make a device to analyse all my results, work out what they mean and what to test next then I wouldn’t need to be here at all….wait :s
My experiments can take between 30 minutes for the shortest type, which unfortunately, are the rareest type.
However, my main experiments, which is growing bacteria and competing them against each other to see who grows the fastest, can take up to a week, and then it will take several hours of calculations to figure out who actually won!
This is why you need a lot of patience as a scientist!