Sauer:Nucleic acid quantitation

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Ambion has a good site that gives a variety of parameters for nucleotides and nucleic acids [http://www.ambion.com/techlib/append/na_mw_tables.html].
Ambion has a good site that gives a variety of parameters for nucleotides and nucleic acids [http://www.ambion.com/techlib/append/na_mw_tables.html].
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===Intro===
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Lot's of ways.  I like the spec.
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===Measuring nucleic acid concentration in a spectrophotometer===
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Pipette your nucleic acid sample into a cuvette and record an absorbance scan from 240-340 nm.
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Most calculations are done from the Abs at 260 nm.
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====DNA====
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Divide the absorbance at 260 nm by 0.02 for dsDNA or 0.027 for ssDNA.  This is the "concentration" in μg/mL.  Actually, to get concentration, you have to know the length of your molecule and use the mass/volume to calculate a concentration.
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===RNA===
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ss RNA, Divide by 0.025.  There is no good way of calculating a value for folded RNA so see the next entry.
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===Making your own Extinction coefficients===

Revision as of 18:53, 25 January 2007

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The originator actually mean "quantification" sorry.

Ambion has a good site that gives a variety of parameters for nucleotides and nucleic acids [1].

Contents

Intro

Lot's of ways. I like the spec.


Measuring nucleic acid concentration in a spectrophotometer

Pipette your nucleic acid sample into a cuvette and record an absorbance scan from 240-340 nm.

Most calculations are done from the Abs at 260 nm.

DNA

Divide the absorbance at 260 nm by 0.02 for dsDNA or 0.027 for ssDNA. This is the "concentration" in μg/mL. Actually, to get concentration, you have to know the length of your molecule and use the mass/volume to calculate a concentration.

RNA

ss RNA, Divide by 0.025. There is no good way of calculating a value for folded RNA so see the next entry.

Making your own Extinction coefficients

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