PCR inhibitors are organic and inorganic contaminants included in the DNA sample that interfere by attenuating or completely inhibiting the PCR amplification reaction. Fortunately, there is a wide range of methods and commercial kits that allow you to get rid of various PCR inhibitors.
This review focuses on the general properties of PCR inhibitors and their occurrence in specific matrices.
Wiley Online Library
This post focuses on the signs that inhibitors are causing problems with quantitative PCR.
Promega Connections
Describes different types of PCR inhibitors and answers questions about the effect of some PCR inhibitors on PCR amplification and how to reduce inhibitors from PCR reaction.
Genetic Education