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What will be a quickest and easiest way to determine if something is
in solution or in suspension e.g. carbamazepine? Thanks for your help.
Dlewar
********************************************************************************
M. Delwar Hussain, Ph.D.
Assistant Professor of Pharmaceutics
School of Pharmacy
University of Wyoming
Laramie, WY 82071-3375
Tel:(307) 766 6129
Fax: (307) 766 2953
E-mail: delwar.-at-.uwyo.edu
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A spectrophotometer.
Hoyt Hillman
MR&D and Product Definition
HazCom and Medical Monitoring
Safety Administrator Org 3-1381
Phone (316) 523-1447, Fax 526-3640
Messages(316)523-1690, Mail K12-17
hoyt.hillman.at.boeing.com
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It appears from your question that you cannot physically tell the
difference. In such a case you may want to try a simple experiment. Take the
solution(?) of your compound in a beaker and place the beaker in the path of
a beam of light (this beam of light may be critical --as I'll explain later.
For starters try ordinary white light). Observe the beaker at right angles
to the incident beam of light. If you have a solution you will see the
contents of your beaker uniformly illuminated. If you have a suspension the
contents in your beaker will show light scatter (as seen by light flashes
appearing from the beaker). This effect is called Tyndall effect and is well
known in spectroscopy. As you have realized by now, the scattering of the
light is a function of the particle size in your suspension and therfore
this is dependent on the wavelength of the incident light. You may have to
try different wavelengths of incident light to confirm whether you have a
suspension or solution.
An alternate method using the same concept is to place your sample in a
fluorescence cuvette and place it in a variable wavelength
spectrofluorimeter. Keep the emission monochromator locked at a single
wavelength (preferably the maximum emission wavelength for carbamezapine).
Let the excitation monochromator scan through the visible spectrum and
observe and record the `absorption' spectra (remember you cannot measure
this absorption spectra in a UV-Vis Spectrophotometer). As the particles of
your suspension scatter the incident wavelengths of light the emission
photomultiplier will register these as `spikes' which will appear on your
recording.
Good Luck and hope this is helpful
Anup Zutshi
Battelle Pulmonary Therapeutics
Battelle Memorial Institute
Columbus, OH
zutshi.aaa.battelle.org
(614) 424-5997
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Copyright 1995-2010 David W. A. Bourne (david@boomer.org)