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thermal cyclers - (Dec/01/2004 )

Working on different thermal cyclers (MJ research, perkin-elmer, eppendorf,...), we have observed a big difference in sensitivity between all the cyclers. I knew that these diffenrences exist but I do not know exactly why: difference in temperature accuracy, speed of temperature variation,.... others???
Second, if a thermal cycler has not been used for several weeks, it seems that it works not so good. Has someone already observed this?

-gipoc-

I have noticed, as have many other peoplethat there is quite a large variation between thermalcycler makes, this is probably due to circuit differences in the peltier block or controls. Usually it is best if you can stick to one machine type for your reactions, at least you know you will get a result with it. My former supervisor used to insist that we list the thermalcycler make in any report/paper we were writing. I guess she had difficulties with the variation between types before.

Some cyclers such as the Eppendorf Mastercycler have an option for altering the ramping speed in degrees per second, which can be useful for large templates and delicate reactions.

QUOTE
Second, if a thermal cycler has not been used for several weeks, it seems that it works not so good. Has someone already observed this?


I havn't noticed this at all, but then the machines I have been using are all used at least once a week.

-bob1-

yeah, this is the bad part of the thermocyclers.
even i have observed the same, i followed the thermal programme of perkin elmer (which has been published) i didn't get the amplification in eppendorf. finally i have standardize the thermal program (annealing temp.)got the the amplification. which i have checked by restriction analysis for the conformation.

Chukles...

ravi
INDIA

-ravibiot-