?what is better for protein precipitation ammonium acetate or sodium chloride in - (Jul/09/2019 )

As I recall, sodium chloride itself can co-precipitate with the DNA in the last ethanol –ppt  step, leaving you with “salty” DNA pellets. So my mentor of long ago recommended either sodium or ammonium acetate, which are less likely to co-precipitate. However I must admit to using commercial kits for most of the last years of my career.  What kind of DNA are you extracting (plasmid, genomic?) and from what organism? ( Gram neg. or gram pos. bacteria, mammalian cells, tissues, plants?)  What’s the lysis protocol?  At what step are you adding the salt?  All these thing might matter to the answer.

That won't work- because if you are adding equal amounts of four 100mM solutions together, you are increasing the total volume by a factor of 4 and therefore diluting each dNTP 1/4.

What I do is add 10ul of each dNTP then make up to 100ul with nuclease free water for a 1/10 dilution. Thanks

@iosman987 - I think you answered the wrong question...