How can I determine the weight of DNA in my sample for genomic extraction?

[hivesaeed4]

This is my first time isolating the whole genomic DNA from cells. I have two cell line HeLa and Human fibroblasts (almost fully confluent T-25 flasks). The problem is that the protocol which is to be followed for genomic dna extraction is only suitable for DNA solutions less than or equal to 1mg/ml (according to the instructions). How do I determine the weight of DNA that I have beforehand? I'm confused on that point. (Note I can't count cells either).

 

[gravenewworld]

Assaying for DNA is very routine, not very expensive, and not hard. Buy a kit:

http://www.lifetechnologies.com/order/catalog/en/US/adirect/lt?cmd=catDisplayStyle&catKey=14001&filterDispName=DNA%2526frasl%253BRNA%2BQuantitation%2BAssay%2BKits&_bcs_=H4sIAAAAAAAAAI1P0QrCMAz8mr44HN0KutfpUEQQQfS9dNEVWitt5tjfe0MEn0QId01y9C7zQsjq%0AGEPbG06ZKBfZieLTGko%2F5h3zQ6halBvUMAy5s1diMt09uHCzlHITPFZ9AtAd0AVPoBBbinnH3uEX%0AUaqpZMWxp6mXSwkqZAFlVcpihm5v3%2Fbaw3GV1Snp8f8Iqq7kxxZsNGtsP6HOJ4BubSTDeDkWamN8%0AK1Szu2wPEDc2PZwe15rpFuKIGBjuaYRiyvd9w1W7NB3xAijCMNBQAQAA
http://www.sigmaaldrich.com/catalog/product/sigma/dnaqf?lang=en&region=US

If you are out of the linear range of the assay, keep diluting your sample until you're in it and keep track of the number of dilutions to figure out how much is in your main sample.