Pharmacia GeneQuant DNA calculator opinions wanted
denomme at FHS.CSU.MCMASTER.CA
Mon Oct 17 00:40:44 EST 1994
On Fri, 14 Oct 1994, Robert Woodward wrote:
> In article <13OCT199411083880 at zeus.tamu.edu> pkr1674 at zeus.tamu.edu (PENNY RIGGS) writes:
> >We're considering purchase of Pharmacia's GeneQuant photometer.
> >Any opinions pro or con would be appreciated.
> We tested one last year - it was difficult to use so we didn't buy it. You
> have to make sure you put the cuvette in an exact position and at the right
> time or the machine will give an erroneous reading. If this is a
> sample you will usually be able to tell that the reading is quite a bit off.
> When this happens for the reference, however, it can mess up a bunch of
> readings. It has been a while so I don't remember anything beyond what I've
> Robert Woodward, c557652 at mizzou1.missouri.edu
> Department of Physiology, University of Missouri
> (314) 882-5374, FAX:(314) 884-4276
You're right. The cuvette must be placed in the machine immediately after
a message 'beep' or you have to start again. Also the cuvette must be
removed after a 'beep'. Bit of a pain, but standing at a spectrophotometer
to do DNA quantitation is just as tedious to me. However, I have found
that people generally have a great deal of difficulty using the
ultra-microcuvette (5 uL sample vol). It is very difficult to tell if
there is an air bubble in the cuvette. For a properly filled cuvette the
light path looks about the size of a pinhead. When there is an air bubble
the size is more like the end of a pin. Some people have trouble seeing
the difference. Air bubbles in the cuvette was probably the
source of your trouble not placing the cuvette in the chamber.
All in all, some people have tried the machine and walked away
frustrated - a few of us use it without difficulty. For large numbers of DNA
samples, the GeneQuant is a time saver and carry-over between samples is
negligible. I'd check out the one with printer capabilities though.
denomme at fhs.csu.mcmaster.ca
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