I am very new in the behaviour field. I have been trying to perform attraction/avoidance assays and got stuck at the point when worms were happily crossing Cu barrier. we have been using 5-250mM Cu acetate barrier (drawn a day before doing the assay), but this does not stop worms from crossing it. Only success so far was with freshly drawn barrier; when just dried - it stopped worms, but also not for very long time. I would appreciate any comments on Cu concentrations and conditions to stop the worms from crossing the barrier.
I am also very new to the field, but from what I’ve read, the condition of the plates (how dry or wet) is very important for behavior assays. I would suggest testing your negative and positive control strains with plates that are poured on different days. Once you have found a set of plates that work with your control strains, note the weight of the plate (this should give you an idea as to how much moisture is in the plate, assuming all plates contain the same volume of media). Then you can use this same “weight” plate for your experiments and hopefully get consistent behavior. Hope this makes sense. Good luck!
If you want to control the volume of each plates, you can also use falcon tubes when pouring plates - first pour agar from bottle to a 50mL falcon tube (of course it should be sterile), then pour again from the tube into plates. If the tube gets messy you just replace a new one.
Hope this works!
Thank you for your replies, I will try to play around with plate conditions