Hello Kirk, 
I hope you meant NaCl solution and Not NaOH. That would be a big mistake to use it anywhere near any lens since the fumes/not to mention the liquid form is extremely corrosive.

Hank Adams
Integrated Microscopy Core
Molecular and Cellular Biology
Baylor College of Medicine
Houston, Texas
-----Original Message-----
From:   Kirk Czymmek [SMTP:[log in to unmask]]
Sent:   Thursday, January 18, 2001 2:19 PM
To:     [log in to unmask]
Subject:        Re: Light Microscopy Course Reminder

        Has anybody ever experienced etching of the metal or glue holding the
lenses in an objective lens by salt solutions? We have a researcher who has
been using up to 1M NaOH solutions in perfusion experiments for the last
year. Occasional minor leakage occurred early on, which caused some
corrosion at the base of the objective lens. We have stopped the leakage and
have devised a way to prevent any solution getting down the body of the
objective lens or elsewhere on the microscope. Last fall I noticed that the
light throughput just didn't seem to be as high and now it has become
terrible. This, of course, was my most expensive lens, 63X C-Apochromat NA
1.2.. I am suspicious of the salt solutions because we only use distilled
H2O on this objective otherwise. The edge of the front lens element seems a
bit irregular compared to the other lenses. I don't know enough about how
these lenses are put together to determine if this is even possible. I just
don't want to switch to a new objective and have the same thing happen.
Also, I do have a call in to the manufacturer, but was wondering if others
might have had a similar experience. Thanks in advance for any thoughts.

Regards, Kirk


Kirk J. Czymmek, Ph.D.
Associate Professor
Department of Biological Sciences
Delaware Biotechnology Institute Bio-Imaging Center, Director
University of Delaware
Newark, DE 19716
(302) 831-1158