Polymerase chain reaction (abbreviated PCR) is a laboratory technique for rapidly producing (amplifying) millions to billions of copies of a specific segment of DNA, which can then be studied in greater detail. PCR involves using short synthetic DNA fragments called primers to select a segment of the genome to be amplified, and then multiple rounds of DNA synthesis to amplify that segment.

Polymerase chain reaction (PCR) machines are cost-effective and highly efficient tools used to amplify small segments of DNA or RNA that are selected from the genome using a primer. 

Also known as PCR systems, thermal cyclers, or thermocyclers, these devices combine the principles of nucleic acid replication with complementary nucleic acid hybridization to exponentially produce specific target DNA/RNA sequences by a factor of 10 7 within a matter of hours.

The PCR technique, invented by Kary Mullis, works by binding primers to the target sequence and extending this using a Taq polymerase (thermus aquaticus). The basic steps of conventional PCR are broken up into three stages, however, a huge variety of modifications exist. 

Because of their ubiquity and power, PCR systems are sought-after by countless scientists, researchers, and technicians, across a wide range of studies, including viral infection testing such as the SARS-CoV-2 virus of the COVID-19 pandemic.

A PCR machine, which is more commonly referred to as a PCR system, is used to make millions of copies of an initially small segment of DNA. 

This process is also sometimes referred to as “molecular photocopying”. It allows scientists to amplify DNA enough to study in detail, making it an incredibly valuable piece of equipment in both clinical and research settings.