>I assume this comes from salts and stuff that are not properly cleaned up
>after the thermocycling. I notice this with samples that are EtOH ppt but
>don't remember if this also occurs with centri-sep purified samples.
>>Is my hypothesis correct? Must I tell my users to buy those expensive but
>useful centri-sep columns? What is that new EtOH protocol that is floting
>around (I tried to access it from an archived message, but the address
>didn't work properly). Other comments?
Your assumption seems to be correct, but there is no ultimate need for
centri-sep or other spin columns. Just wash your samples once or twice
70% EtOH, it helps.