Calculating moles from base pairs ??

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    • #16368
      lulubell
      Participant

      Hi,
      I’m trying to figure out the moles of a piece of DNA- using just the following information …..

      The genomic DNA is 20000ng (mass) and is 15000 base pairs long

      I know to get moles you have to do; Mass/ relative formula mass <— but I don’t know this….

      Is it possible to do; mass/base pairs to get the number of moles?

      In which case it would be 20000/15000 = 1.333 M ??

      I then need to find the mass (in ng) in 1 mole- I know how to do this, but obviously if I get the first part wrong, my answer here will be wrong also

      Any advice?

    • #110670
      JackBean
      Participant

      1500 bp is not molecular weight. For this you need average weight of nucleotide and with the number of nucleotides in molecule you calculate the molecular weight of the whole molecule. hat you use to calculate concentration.

      But the concentration of DNA is usually in mass per volume (e.g. ng/ul).

    • #111068
      taruntbiotech
      Participant

      see this hope it will help u

      Single-stranded: 330 grams per mole per base
      330 (g/mol)/b
      330 g / ( mol • b )

      Double-stranded: 660 grams per mole per base pair
      660 (g/mol)/bp
      660 g / ( mol • bp )

      Example problem:

      Find the number of moles which compose a 1.5kb band whose mass was determined to be 120 ng (by gel comparison to standards).

      (120 n g ) • ( mol • bp ) = 1.2E-4 nmol or 0.12 pmol
      (1500 bp) ( 660 g )

    • #111069
      taruntbiotech
      Participant

      molbiol.edu.ru/eng/scripts/h01_07.html
      also check this

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