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Removal of PCR inhibitor - (Mar/29/2006 )

Does anybody know a good technique for the removal of humic acids from extracted DNA. I have collected some environmental samples, and performed DNA extraction using a general Phenol Chloroform Isoamyl alcohol method, and I know I have humic acids inhibiting my PCR (16S rRNA primers for general bacteria). My samples are eluted to a volume of 100ul and have a faint yellow colour about them indicative of humic acids. mad.gif


you can try increasing the mg content of your pcr reaction to compensate for the chelation caused by the humic acids.

maybe etoh precipitation will leave them behind?

more info on humic acids:


We are working with a lot of environmental samples in our lab, and have some problems with inhibitor. Until now the best we had were with kits from Mo-Bio .
Their last Power soil kit was definitely a plus with some really annoying sample.


Thanks for your time guys.