Hyperchromicity of DNA

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klou
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Hyperchromicity of DNA

Post by klou » Fri Nov 27, 2009 6:14 pm

In an experiment to determine the Hyperchromicity of DNA, the absorbance value for undenatured DNA was 0.390 and the value for heat- denatured DNA was 0.790. Calculating the percentage increase gave me a 102% increase, where it should have been around 40-50%! What possible reasons could there be for this large increase?
Last edited by klou on Sun Nov 29, 2009 1:03 pm, edited 1 time in total.

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JackBean
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Post by JackBean » Sat Nov 28, 2009 12:12 am

I think, you have swithed the values, didn't you?
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

klou
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Re:

Post by klou » Sat Nov 28, 2009 4:08 pm

JackBean wrote:I think, you have swithed the values, didn't you?


I'm not sure what you mean.
The calculation for the hyperchromicity is (A260 denatured - A260 control) / A260 control x 100
Which gives 102%

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JackBean
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Re: Hyperchromicity of DNA

Post by JackBean » Sun Nov 29, 2009 1:43 am

klou wrote:the absorbance value for undenatured DNA was 0.790 and the value for heat- denatured DNA was 0.390.

I think this. I think, that the denatured DNA has higher absorbance, doesn't it?
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.

klou
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Re: Hyperchromicity of DNA

Post by klou » Sun Nov 29, 2009 1:02 pm

JackBean wrote:
klou wrote:the absorbance value for undenatured DNA was 0.790 and the value for heat- denatured DNA was 0.390.

I think this. I think, that the denatured DNA has higher absorbance, doesn't it?


I got it the wrong way round in my first post. But I did the calculation correctly, so that doesn't change the result.

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