分光光度分析核酸浓度

互联网2013-09-05

1062

This program helps you to calculate the concentration of nucleic acids according to their optical density. (DNA, RNA, oligonucleotides). It is better to use {OD₂₆₀ -OD₃₂₀ } instead of OD₂₆₀ . For a series of measurements (batch mode) you should insert in the "Absorbance OD₂₆₀ " field the optical densities separated by the space.

Sample: dsDNA ssDNA RNA olig

- 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:        µg/µl    ng/µl    pg/µl

Results for the "batch mode":
</td> </tr> </tbody> </table> <p><font face="Arial" size="2"/> </p> <p><font face="Arial" size="2">Help for "spectrophotometric measurement"</font> </p> <p class="tx"><font face="Arial" size="2">Let's suppose, that 1.5µl of RNA was diluted in 2ml of water and the optical densities: OD<sub>260</sub> =0.253, OD<sub>320</sub> =0.005 (so, OD<sub>260</sub> -OD<sub>320</sub> =0.248).</font> </p> <p class="tx"><font face="Arial" size="2">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".</font> </p> <p class="tx"><font face="Arial" size="2">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).</font> </p> <p><br/> </p> <table cellspacing="0" cellpadding="5" width="580" border="0"><tbody><tr><td valign="top" align="middle" width="200" bgcolor="#dddddd"><font face="Arial" size="2">Sample: </font> <select onchange="rclc1()" name="NA"><option> dsDNA </option> <option> ssDNA </option> <option selected="selected"> RNA </option> <option> olig </option> </select> <br/> <font face="Arial" size="2"> <br/> <br/> <input type="checkbox" name="batch" _cke_saved_name="batch"/> </font> <font face="Arial" size="2">- choose for the "batch mode".<br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> </font> <input type="reset" value="Reset"/> <font face="Arial" size="2"> </font> </td> <td valign="top" align="right" width="380" bgcolor="#eeeeee"><input onchange="spctr()" size="3" value="40" name="K" _cke_saved_name="K"/> <font face="Arial" size="2"> [µg/ml] </font> <font face="Arial" size="2">- extinction coefficient <br/> it would be better to use special for oligonucleotide <br/> <br/> Dilution volume: </font> <input size="5" value="2000" name="V" _cke_saved_name="V"/> <font face="Arial" size="2"> µl<br/> Sample volume: </font> <input size="5" value="1.5" name="v" _cke_saved_name="v"/> <font face="Arial" size="2"> µl<br/> Absorbance OD<sub>260</sub> : </font> <input onchange="spctr()" size="25" value="0.248" name="A" _cke_saved_name="A"/> <font face="Arial" size="2"> <br/> </font> <input onclick="spctr()" type="button" value="Calculate"/> <font face="Arial" size="2"> <br/> Concentration: </font> <input onfocus="this.blur()" size="8" name="C" _cke_saved_name="C"/> <font face="Arial" size="2"> </font> <select onchange="rclc()" name="D"><option selected="selected"> µg/µl </option> <option> ng/µl </option> <option> pg/µl </option> </select> <font face="Arial" size="2"> <br/> </font> <hr/> <font face="Arial" size="2"> Results for the "batch mode": <br/> </font> <textarea onfocus="this.blur()" name="btx" rows="5" cols="40"/> </td> </tr> </tbody> </table> <br/> <br/> </span> </p><p class="tx"><font face="Arial" size="2">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 OD<sub>260</sub> " the string: <font color="red">0.248 3.46 0.487 0.007 0.122</font> . Result of calculations should be:</font> </p>