Hi Connie,

According to Polysc's web site, their MMA is like Fishers and Bakers,
each with 25 +/- ppm of HQ.  When I changed jobs a few years ago, I
was looking for sources of equivalent HQ content (as R & H)  -
without luck -- So, I tried the Fisher monomer, and did not find
measurable differences in infiltration, embedding, polymerization,
staining or section adherence.  I found it interesting.  (I do not
remove the HQ, nor do I use PMMA beads.)

Thanks for confirming what I 'heard' years ago too.

Mary

>>> connie mcmanus <conmac@cc.usu.edu> - 10/1/98 3:20 PM >>>
Mary,

Your comments on greening an acid indication... it all comes back to
me now
(it's been over 15 years ago)... these are the things my mentor,
Rosmarie,
told me when I was being trained in this.  She also pointed out that
R&H's
MMA had the highest ppm of HQ of any other MMA available.  I was
hoping all
MMA was up to this standard by now, but I guess not.

Polysciences people... what ppm of HQ is in your MMA?

Connie McManus
Veternary Diagnostics Lab
Utah State University
Logan, Utah





>
>Sometimes I feel like working with MMA/bone is like encountering
>aliens - not that I've had that "experience" - but can only imagine!
>
>Regarding the 'green tinge' thing, I 'heard' it was because it was
>starting to go acidic - aka breaking down, impurities may be a
better
>explanation since it's still within the shelf life provided.  What I
>don't know is why different companies which sell MMA have such
varied
>shelf life dates for their products.  I'm sure the HQ concentration
>effects it, but Fisher and Baker have ~ the same, as does the
>Polysciences.  I recall Rohm & Haas used 60ppm HQ, and we used to
>always order it with "date stamped less than 1 year from
>manufacture."   I just double checked our Fisher and Baker bottles
--
>neither has an expiration date on them!!  After all this is said, I
>think I will try the Polysciences product next!
>
>Ah.... the wonders of MMA -