Hi Ali,

Problem usually in these type of experiment is loading the structure in
a significant way (atleast in my experience).

It takes a long time to load the dye in an already filled structure. It
is therefore easier often to activate the dye after having loaded it.

Did you consider using photoactivated dye, load the entire structure
with it, than selectively activate a small portion, and look at the
diffusion of that signal? You can also do the contrary experiment by
loading a structure with dye, photobleaching a small section, and then
look at the diffusion back into the structure...Photobleaching recovery
is often called "FRAP"

A quick googling of "Photoactivated fluorophores" yields this,
http://adsabs.harvard.edu/abs/1993aiaa.meetQX...L , and you can also
find things like http://www.biophysj.org/cgi/content/full/75/1/557 .

Hope this helps,

M.

-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of Ali Muhammad
Sent: Sunday, November 26, 2006 7:05 AM
To: General MEMS discussion
Cc: biomems@gmail.com
Subject: Re: [mems-talk] Re: Trying to Study Diffusion profile

Hi,
I havent tried any real good at present, I am not able to think of a
good way to do this experiment. I want to have some advice how to do
this experiment, getting a good diffusion profile and to be able to
measure it at the same time.

Has there been any good study in this regard, If there is, can u refer
me some papers or websites. I would love to have some advice as well.