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<p class="MsoNormal">Hello all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Our lab wants to explore the use of paraformaldehyde as a whole-specimen fixative, to be carried as a dry powder to locations where formalin cannot be obtained. Simmons’
<i>Herpetological Collecting and Collections Management</i> describes two major disadvantages of solid paraformaldehyde: 1) it is extremely alkaline in solution, to the point that it may cause specimens to clear, and 2) it does not dissolve readily and requires
some effort and boiling water to form a solution of appropriate concentration for fixing specimens. The same work also details a 1989 protocol by Ehmann to mitigate these issues through addition of anhydrous sodium bicarbonate, a wetting agent, and citric
acid powder.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Can anybody vouch for Ehmann’s method or offer other tips or tricks for buffering and dissolving paraformaldehyde to ensure quality (fish) specimens? I doubt there is enough demand for any supplier to offer premixed, neutrally-buffered
powders—but if you know of one, please let me know.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance,<o:p></o:p></p>
<p class="MsoNormal">Dave<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;mso-ligatures:none">David A. Boyd, MSc<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;mso-ligatures:none">Collections Manager, Ichthyology and Herpetology<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;mso-ligatures:none">Louisiana State University Museum of Natural Science<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;mso-ligatures:none">119 Foster Hall, Baton Rouge, LA 70803<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;mso-ligatures:none">(225) 681-0456</span><span style="mso-ligatures:none"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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