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Help for "spectrophotometric measurement"

Let's suppose, that 1.5µl of RNA was diluted in 2ml of water and the optical densities: OD260=0.253, OD320=0.005 (so, OD260-OD320=0.248).

Fill these data to the form as it is shown below and push "Calculate". You will obtain: "13.23µg/µl". If you want the answer in "ng/µl", just select this unit and you will have: "13230ng/µl".

Now, change optical density to 0.015 and just click somewhere outside the field (or, again, push "Calculate"): program will give "800ng/µl". In the same way the program will recalculate answer after changing other parameters (volume, nicl. acid type).


Sample:  
 
 
 - choose for the "batch mode".
 
 
 
 
 
 
 
 [µg/ml] - extinction coefficient       
it would be better to use special for oligonucleotide       


Dilution volume:   µl
Sample volume:   µl
Absorbance OD260:    
  
Concentration:       

Results for the "batch mode":       


Finally, let's suppose, that in the same conditions you have obtained for a seria of samples the following densities: (i) 0.248; (ii) 3.46; (iii) 0.487; (iv) 0.007 and (v) 0.122. Choose the "batch mode" and insert in the field "Absorbance OD260" the string: 0.248 3.46 0.487 0.007 0.122. Result of calculations should be:

1 -- 0.248 -- 13.23µg/µl
2 -- 3.46 -- 184.53µg/µl
3 -- 0.487 -- 25.97µg/µl
4 -- 0.007 -- 373.33ng/µl
5 -- 0.122 -- 6.51µg/µl


"Practical Molecular Biology" http://molbiol.edu.ru;
e-mail: pmb@molbiol.edu.ru


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