Omega Engineering 48, 20, 30, 25 manual Notes on transferring protocols from other thermal cyclers

9. Notes on transferring protocols from other thermal cyclers

The CYCLER TCY heats at over 3.6°C/s and provides the highest levels of temperature uniformity. Many slower machines have historically begun the countdown on hold times before the set temperature is reached in order to avoid any overshooting in sample temperature. The slower the heating rate the more significant the loss in hold time, i.e. if a 30 second hold time is set at 55°C then perhaps 5 to 10s will be lost in between the start of the time countdown and actually reaching the set temperature. The overall effect of this method of control is that your sample, if cooling from a higher temperature, is subjected to an environment with an elevated temperature compared to the target temperature for a significant part of the hold time.

The CYCLER TCY provides the user with ‘what-you-program-is what-you-get’. Due to the rapid and responsive nature of the Peltier heating system, the time between the timer countdown initiating and actually reaching the set temperature has been reduced to as little as 1s. This ensures that the sample is only subjected to the exact temperature required.

Taking the above into consideration it must therefore be noted that care must be taken when re- optimizing protocols from a slower machine.

Trouble Shooting

1.The optimum annealing temperature may in fact be higher than the set temperature used in the slower machine. Try increasing it by 1 or 2°C.

2.The hold time can be reduced once the optimum temperature has been found. Try reducing it by 5 to 10s.

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