hi there,

i am noew constantly getting a late peak (30+ cycles) in the negative controls for my real-time pcr (SYBR Green, iCycler). i have even bought in new nuclease free water to run as my negative contro, and still get these peaks... does this mean my primers are contaminated????

Your working primer stock could well be contaminated, when you say it's great than cycle 30, how much greater? if it's high 30's ie greater than 35 then I would not worry too much about it.

One other thing is to check the reaction by running it on a gel, if a distinct band comes up in your negative control(and it looks like the test lanes) well that would answer your question.

Good luck!

Nick