Jonathan Redfern 100537.271 at CompuServe.COM
Mon Aug 28 11:13:22 EST 1995

Regarding the Robocycler:

I write from Techne(UK) to pass on the experience we have with 
testing the Robolcycler.

We find the idea of moving the sample tubes from block to block 
does not infact remove the ramping time as the time is required 
for the thermal transfer of energy through to the sample.

At Techne we find the fastest crossover of heat to sample is 
approx 3°C/sec,(thin wall tube 0.2ml and 0.5ml), this does 
increase of course as the tube temperature increases and becomes 
slightly more conductive.

A number of the faster Thermal cyclers on the market now ramp at 
speeds of 3°C/sec, including the Techne GeneE and the new, 
(available September), XXX cycler. Because the ramping speeds are 
equial to the thermal transfer rate the Robocycler offers no 
advantage on this point.

Another finding was that the sample actually experienced a drop 
in sample temperature whilst being transfered between blocks, 
thus increasing the possibility of non-specific reactions 

More information about the Methods mailing list