PCR inhibitors - occurrence, properties and removal

J Appl Microbiol. 2012 Nov;113(5):1014-26. doi: 10.1111/j.1365-2672.2012.05384.x. Epub 2012 Jul 24.


The polymerase chain reaction (PCR) is increasingly used as the standard method for detection and characterization of microorganisms and genetic markers in a variety of sample types. However, the method is prone to inhibiting substances, which may be present in the analysed sample and which may affect the sensitivity of the assay or even lead to false-negative results. The PCR inhibitors represent a diverse group of substances with different properties and mechanisms of action. Some of them are predominantly found in specific types of samples thus necessitating matrix-specific protocols for preparation of nucleic acids before PCR. A variety of protocols have been developed to remove the PCR inhibitors. This review focuses on the general properties of PCR inhibitors and their occurrence in specific matrices. Strategies for their removal from the sample and for quality control by assessing their influence on the individual PCR test are presented and discussed.

Publication types

  • Review

MeSH terms

  • False Negative Reactions
  • Nucleic Acid Synthesis Inhibitors
  • Polymerase Chain Reaction / methods*
  • Polymerase Chain Reaction / standards
  • Quality Control
  • Specimen Handling / methods*
  • Specimen Handling / standards


  • Nucleic Acid Synthesis Inhibitors