Thermal cyclers, also known as a PCR machines or DNA amplifiers, play an important role in many laboratories. The primary function of the machine is to carry out the polymerase chain reaction (PCR) process, which amplifies DNA. Researchers use the amplified DNA to carry out a variety of activities including gene mapping, DNA fingerprinting, diagnosis of genetic disorders and identification of bacteria and viruses.

Thermal cyclers are expensive pieces of equipment. Therefore, prior to purchase, it's best to complete a thorough review of available thermal cyclers. List the thermal cycler qualities that are important to you. Then identify a few machines that may work. Here are some things to consider when comparing thermal cyclers:

1. Newer thermal cyclers come with a heated lid that staves off the build-up of condensation from reaction tubes.

2. You must apply wax or oil to older thermal cyclers that aren't equipped with the heated lid.

3. Certain thermal cyclers contain multiple blocks, allowing the researcher to complete several unique PCR reactions at the same time.

4. Advanced thermal cyclers employ the Peltier effect, which allows for heating and cooling within the block.

5. Gradient thermal cyclers allow for a temperature differential across the block.

Action Steps
The best contacts and resources to help you get it done

Find simple, cost effective thermal cyclers

If the nature of your research doesn't require anything fancy, then you can save money by buying a simple thermal cycler. Standard thermal cyclers are also beneficial if workspace is limited.

I recommend: Techne offers the TC3000, which is advertised as a low-cost personal cycler. This particular thermal cycler has interchangeable blocks and uses the Peltier technology for heating and cooling within the block. It also has one of the smallest footprints in the marketplace. LABREPCO offers the Biometra TPersonal thermal cycler, which is the smallest of Biometra’s thermal cycler products. It is a good product for researchers with a small budget and limited bench space.

Find multiple block thermal cyclers

Larger laboratories frequently require multiple block thermal cyclers that permit multiple users to operate simultaneously and independently.

I recommend: Thermo Fisher Scientific offers the Px2 Thermal Cycler. This machine comes with six blocks. It's also unique in that it offers five control modes for precise temperature control. If you have a busy lab, with many researchers consider the MJ Research 'Tetrad' DNA Engine, offered by GMI. This thermal cycler has eight separate blocks, capable of running simultaneous or independent reactions.

Locate gradient thermal cyclers

If you're looking for a thermal cycler that allows you to vary the temperature from one side of the block to the other, then you'll want a gradient thermal cycler.

I recommend: Progen Scientific offers the LabNet Multigene 96-well Gradient thermal cycler. This thermal cycler offers Peltier technology and a heated lid. It has a 12 row gradient function horizontally across the block. Quanta Biotech has the QB96 Server Gradient Thermal Cycler. This thermal cycler also comes with Peltier technology and linear gradients up to 30 degrees Celsius.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Find a thermal cyclers provider that sells used equipment. Keep in mind that there's a trade-off with used equipment. You may save money, but you'll likely miss some of the modern features, such as the heated lid.
• •  When reviewing thermal cyclers information, consider the quality of the keypad. While it's not vital to successful PCR, user-friendly keypads help.
• •  As you look through a thermal cyclers directory, consider the footprint of the thermal cycler. If you don't have a lot of space, you'll want to find a thermal cycler with a small footprint.