"Marvin Margoshes" <[Only registered users see links. ]> wrote in message news:<[Only registered users see links. ]>...
FROM THE OFFICES OF TONY BLARE:
You're in luck...FAME...that's right, FAME.
Fatty Acid Methyl Esters...you derivitize the
s**t and then use a gas chromatograph to do
the analysis. We've done it in this country:
George Bush the First is derivitized to
George Bush the second. BTW, gas chromatography
is based upon a "hot gas" approach to determining
what is going on in the real world.
But, before you get your hands dirty doing
real chemistry, check with the CRC (in the
USA, that means the Chemical Rugby Company
Handbook of Chemistry and Phlacids). IIRC,
there is a specilised volume published by
the CRC dealing with analyses of human
stuff, feces included. Then there's the
American Water Works Association's Handbook
of Water and Wastewater Chemistry. Heck,
sewage and sewage sludge compositions must
have been analyzed to death. Worst-case
scenerios...(1) go to paper editions of
Chemical Abstracts; (2) look for books that
were published, say, before 1930 (since then
nothing much has happened :-)
Lipid analysis is usually carried out with TLC method using silica gel (type G with CaSO4 binders) with thickness of 0.25 mm, coated on 20x20 cm glass plate which the adsorbent layer is before clean with soap, removed by washing with tap water, and immersed in 10% solution of alkali for several hours. The plates are then washed with distilled water and dried in a drying oven. It is advisable to activate the prepared TLC plates by heating at 110 °C for 30-60min. After activation the plates are cooled in a desiccating cabinet before applying the sample. The activation step is very important, particularly under humid weather conditions. Total serum lipids are extracted mixing 0.5 ml serum with 4.5 ml of mixture of chloroform/methanol/0.1 M KCl (2:1:1 - v/v). Reaction mixtures are centrifuged at 1500 g for 5 min., the lower phase collected and the upper phase extracted a second time with 600 µl chloroform. Total lipid from the combined chloroform phases is separated by two-step TLC. Samples were first run halfway on a pre-coated SIL G-25 TLC plate home-made or obtained from commercial sources (Macherey-Nagel, Germany) in chloroform/methanol/acetic acid/water (90:15:10:3 - v/v), followed by a second separation using hexane/diethyl ether/acetic acid (70:30:1 - v/v). Different lipid fractions were identified by running appropriate standards alongside and staining with iodine vapour or other stain methods.
For to complete my precedent post, in lipids analysis with TLC method, the first solvent system, consisting of chloroform/methanol/acetic acid/water (90:15:10:3 - v/v), is allowed to run approximately 9 cm from the origin. This solvent system separated the more polar neutral lipids (i.e., fatty acids, fatty alcohols, diglycerides, and monoglycerides), but carry the less polar neutral lipid (i.e., wax ester, triglyceride, and ubiquinone) at the solvent front. These less polar neutral lipids are separated by a second solvent system consisting of hexane/diethyl ether/acetic acid (70:30:1 - v/v) run in the same direction to within 1 cm of the top of the plate (18 cm long).