... do you have any kind of criteria for deciding when to give up on failed lab ideas? I know there are some things that WILL work given huge amounts of time and energy, and with these you have to decide whether it's worth it, but for me it seems like the last two years have been one long string of obstacles which I've been trying to overcome. I'm so gullible - every time I make a modification to my experiment I think 'that'll do it', but it never does... I wish someone could just tell me 'on the three-hundredth modification your experiment will work', but the way things are there's no end in sight!!!