An experiment with labeled AA, added to the dough, ruled out the possibility that AA released by alkali extraction was bound to or entrapped in the matrix.
Tags were purified from a polyacrylamide gel by phenol-chloroform extraction and bound to Streptavindin beads.
Of importance, the addition of an internal standard dissolved in an organic solvent to the plasma sample obviously is not fully adequate for the extraction of lipoprotein bound lipids.
The choice of anticoagulant is important because EDTA, as a strong metal-chelating agent, may be difficult to obtain without some background contamination and may give misleadingly high plasma-Pb results because of selective extraction of Pb bound to erythrocytes.
To extract all noncovalently bound polyamines from pellicles, we used an aggressive extraction procedure using trichloroacetic acid (CCl3COOH).
However, little attention has been given to the nature of the inorganic fraction brought in solution by the alkaline extraction and so strongly bound to the humic material to require a drastic treatment to be released.
Accordingly, a further purification step was performed, namely, ethyl acetate extraction, to abrogate noncovalently bound ICG-sOSu.
Briefly after cell lysis and organic extraction, total RNA was bound to a glass fiber filter, washed and eluted with a proprietary elution buffer.
Double purification was performed first by SE-HPLC to remove the HMW aggregates and LMW impurities, and second by ethyl acetate extraction to abrogate noncovalently bound ICG-sOSu.
First, the solid-phase extraction column (trimethylaminopropyl group bound to silica) concentrates not only the desired XA, but also leave behind urinary substances such as the tryptophan metabolites, kynurenin, and hydroxylkynurenine.
