Hi everyone,

I have a question about isolated DNA QPCR issue. I am isolating DNA three stage of our downstream process and after that when i am doing QPCR analysis with these isolated DNAs, every time my spike values are too much low. İ am trying some way like with my stock sample dilute 10 times and spiked with diluted sample. theoretically my spike concenration value should be 100 and my %recovery limit is %50 to %200 but after the analysis the spike recovery is 36,8 or 19,5 and so on. and trying not diluted sample and same thing..what can i do?  maybe the dilution factor is too much, if i am diluting the sample 5 times or 3 times than it is working. i dont know, and not have explain this stiuation. Maybe isolation kit chemicals masked the DNA spike concentration. The isolation step's last stage is to carry DNA in elution buffer, and i am thinked " maybe elution buffer interference is blocking the DNA concentration" but when i am trying to spike the elution buffer and interestingly the spike concentration is 100 pg.