Real-time chemiluminescence- why?
mbuchho at med.uni-goettingen.de
Mon Feb 15 11:30:25 EST 1999
David L. Haviland, Ph.D. wrote:
> While conducting the search for an imaging system for our institute, I had
> numerous sales reps tell me the "wonders" of their particular machines and
> always made the point about being able to perform "real time
> chemiluminescence" imaging. Basically, performing the actual development
> of the blot while at the same time obtaining the image. I was "slathered"
> with all the gory details about the chips used in the CCD camera and why
> company X's was better than company Y's in performing long duration imaging.
> More importantly, when I asked those in our institute about "real time
> measurement" that perform chemiluminescent assays, I was greeting with
> bizzare looks, and the ever present question of "Why would I want to do it
> that way?"... They prefered just to use film and get a computer image of
> that instead. To some extent this is all moot, since with the system we
> did buy, we can now use a chemiluminescent imaging screen.
> But I'm still curious, why do real time imgaging? From what I've been
> told, it takes an enormous time (tens of minutes or more) to perform, ties
> up the machine, and makes little sense at the moment.
> Anyone care to enlighten me?
if you`re just looking for a documentation system for your western
blots, then x-ray film is indeed the more comfortable solution. "Real
time chemiluminescence" imaging does make sense though when you want to
perform quantitative analysis of your bands, because a CCD camera is
able to linearly record signal strength over several orders of
magnitude. For X-ray film on the other hand, the range of signal
intensities for which the spot intensities on the film rise linearly to
the signal strength is very limited. That means that weak signals as
well as very strong signals can not accurately be quantified.
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