Thermal cyclers are a pretty standard addition to any molecular biology lab. There are many companies out there offering several different models with various capacities and features. We do a lot of PCR in the lab so high throughput was one of our main requirements, as well as the ability to optimize protocols with great reliability. The new 96-well Veriti thermal cycler from Applied Biosystems promised these features.
A main selling point of the machine is the VeriFlex Blocks that make up the 96-well interface. There are six independent peltier blocks that can be set to individual annealing temperatures for PCR optimization. This is nice because it does not assign the temperatures within a certain range as the other machines do, but allows you to pick exact numbers, although the temperatures still must be within 5°C in adjacent zones. A drawback of the instrument is the fact that only one PCR cycle can be run at a time, as opposed to the Bio-Rad iCycler which has the ability to run two 48 cycle blocks separately. However, it is actually possible to run 6 cycles at a time as long as the only thing that differs is the annealing temperature. Another great feature is the touch screen. It is easy to use and fairly intuitive. The instrument can also run fast PCR protocols (requiring the use of special fast PCR reagents) and also has faster run times of standard PCR reactions, with a function that will convert old protocols. It is easy to set up protocols and folders can be created to organize and group reactions. The run time is also decreased, as the blocks ramp quickly; my PCRs are completed probably at least a half hour faster on average. Another feature promised is the networking and computer program control but I haven’t found that useful or necessary.
A drawback of the machine is the noise – it can be pretty loud at times, especially when booting up or cooling. It takes a while to warm up when first turned on and has a pretty slow processing time when responding to requests to stop a cycle or change a feature, etc. Another annoying function is the pause feature – it won’t pause until after the cycle has finished, which doesn’t allow one to start a run and then pause when the block has reached the 95°C starting temperature to place the PCR tubes. The folders can be a little tricky to maneuver through as well, and I haven’t figured out how to make mine the default or to delete the unnecessary preprogrammed protocols.
In conclusion, while there are a few drawbacks to the Veriti, it has lived up to its promise of reliability and ease of use with some fun new features that can save time and increase reliability and throughput.