PREPARATION OF 2% FORMALDEHYDE STOCK SOLUTION (2 METHODS)
互联网
2293
METHOD 1:
Formaldehyde preservative � 2% formaldehyde solution in protein-free phosphate-buffered saline (PBS).
Prepare as follows:
Add 2 g paraformaldehyde powder (e.g., Sigma, St. Louis, MO) to 100 ml of 1 X PBS. Heat to 70 ° C (do not exceed this temperature) in a fume hood until the paraformaldehyde goes into solution (note that this happens quickly as soon as the suspension reaches 70 ° C). Allow the solution to cool to room temperature. Adjust to pH 7.4 using 0.1 M NaOH or 0.1 M HCl, if needed. Filter and store at 4 ° C protected from light.
METHOD 2:
Formaldehyde preservative � 2% formaldehyde solution in protein-free PBS.
Prepare as follows:
<center>
<table>
<tbody>
<tr>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">10% formaldehydundefined</font> </font> </font></font></p>
</td>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">20 ml</font> </font> </font></font></p>
</td>
</tr>
<tr>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">10 x PBS</font> </font> </font></font></p>
</td>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">10 ml</font> </font> </font></font></p>
</td>
</tr>
<tr>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">Distilled water</font> </font> </font></font></p>
</td>
<td>
<p>
<font><font color="#400040"><font><font color="#400040">70 ml</font> </font> </font></font></p>
</td>
</tr>
</tbody>
</table>
</center>
