Which PCR inhibitors can be present in a non-ultrapure dNTP preparation?
A dNTP preparation containing PCR inhibitors resulting from an inadequate manufacturing process can dramatically affect your experiment. Several parameters must be taken into account when purity is defined. Each dNTP should preferably be free of NTPs, other dNTPs, modified nucleotides (methylated, deaminated, etc.), deoxynucleoside diphosphates (dNDPs) and monophosphates (dNMPs), heavy/transition metals, inorganic pyrophosphates (PPi) and tetraphosphates. HPLC is a suitable method of testing dNTP purity, but some contaminants (i.e. PPi) cannot be detected using this technique.
