Size selective DNA precipitation protocol

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<html><h2>Solutions/reagents:</h2><ul type="circle"><li> <a name="DNA sample">DNA sample <i><br><tab><div style="margin-right: 600px;">(DNA to be separated (e.g. PCR reaction mixture))</div></i></a></li><li> <a name="PEG/MgCl2">PEG/MgCl2 <i><br><tab><div style="margin-right: 600px;">(30% (w/v) PEG 8000/30 mM MgCl2 (concentration of PEG 8000 can be varied to shift the size of the percipitated DNA. The concentration used here will remove DNA fragments with less than 300bp))</div></i></a></li><li> <a name="TE buffer">TE buffer <i><br><tab><div style="margin-right: 600px;">(10 mM TRIS-HCl, 1 mM EDTA, pH 8.0)</div></i></a></li><li>buffer of choice</li></ul><h2>Equipment:</h2><ul type="circle"><li>Centrifuge</li><li>Eppendorf tubes</li></ul><h2>Steps:</h2><ol><p><li>Measure out <b><font color=#357EC7>50 µl</font></b> of <a href="#DNA sample" ><font color=#357EC7>DNA sample</font></a> into Eppendorf tube (1).<br>Measure out <b><font color=#357EC7>150 µl</font></b> of <a href="#TE buffer" ><font color=#357EC7>TE buffer</font></a> into DNA sample.<br>Gently tap the mixture for a few secs.<br></li></p><p><li>Measure out <b><font color=#357EC7>10 µl</font></b> of <a href="#PEG/MgCl2" ><font color=#357EC7>PEG/MgCl2</font></a> into Eppendorf tube (1).<br></li></p><p><li>Vortex the mixture for a few secs.<br></li></p><p><li>Centrifuge at a speed of <font color=#357EC7>10000 Xg</font> for <b><font color=#357EC7>15 mins</font></b> at <b><font color=#357EC7>room temperature</font></b>, gently aspirate out the supernatant and discard it.<br></li></p><p><li><font color = "#800517"><i>Carefully remove supernatant not to disturb the pellet, which will be invisible.</i></font><br></li></p><p><li>Add <font color=#357EC7>buffer of choice</font> to pellet.<br><font color = "#800517"><i>Add appropriate volume of buffer.</i></font><br>Dissolve the pellet in the solution.<br></li></p></ol><p><b>TOTAL TIME REQUIRED FOR THE COMPLETION OF THE PROTOCOL :<font color=#357EC7>~ 15 mins</font></b></p></html>