</fontfamily><fontfamily><param>New_York</param>I still see "fading at
base 100-200" like questions popping up so I thought I'd summarize how
we (sort of) solved that problem with the help of people from the ABRF
list and the Automated DNA Sequencing
list.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>We started washing with
Multiterge, using a 20% solution to wash with immediately prior to the
plate assembly and that reduced the fade to the point where we could at
least read thru the fade region.
</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>When we still noticed
fade on a new set of plates we suspected a
reagent.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>As suggested by MR from
UU, we looked at our formamide and found the pH to be 5.5. We then pH'd
a fresh bottle from a different supplier which measured at 6.7. We
tried the fresh formamide and the fade was virtually gone.
</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>We still see some fade
occasionally but, knock on wood, its
manageable.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>Based on info. from
PEABD support, we decided to give a set of plates that we had
mothballed due to haze and fade problems to our glass washing shop
where they use 190 F water plus a 10 min DD water rinse in their
machines. They put the plates thru 3 washes without soap and when we
tried those plates the haze and fade was
gone.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>Three fixes for the
price of one. </fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>If anyone can anyone
explain the science please feel
free.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>Thanks again to all who
helped us out.</fontfamily><fontfamily><param>Times</param>
</fontfamily><fontfamily><param>New_York</param>Dick
Cook</fontfamily><fontfamily><param>Times</param>
</fontfamily>