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Enantiomeric separation by HPLC of 1,4-dihydropyridines with vancomycin as chiral sector
No full textRisoluzione di miscele racemiche di farmaci calcioantagonisti a struttura 1,4-diidropiridinica mediante cromatografia HPLC
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Identification of ten amphetamines with Capillary Electrophoresis coupled to Electrospray Ionization Mass Spectrometry (CE-ESI-MS)
No full textEnantiomeric separation by HPLC of 1,4-dihydropyridines with vancomycin as chiral selector
No full textThe macrocyclic antibiotics represent a relatively new class of chiral selectors in CE, HPLC, and TLC. We have examined the use of the macrocyclic antibiotic vancomycin as a chiral selector in HPLC for the separation of 1,4-dihydropyridines (DHPs) calcium antagonists (CAs). Chromatographic data of six 1,4-dihydropyridine calcium channel blockers obtained on the vancomycin chiral stationary phase (Chirobiotic V) were compared with those obtained on an alpha(1)-acid glycoprotein (AGP) HPLC stationary phase. Optimization of pH and organic modifier was carried out in order to modulate the retention properties of each system. All chiral neutral DHPs were resolved on the AGP column, whereas on Chirobiotic V only basic DHPs showed a split peak. The analytical chromatographic procedure on Chirobiotic V proved suitable for semipreparative separation, since the separation factor on the analytical column was high enough to obtain pure enantiomers with high yields
Supercritical fluid extraction and GC detection of p,p1-DDE and PCB congeners in some samples of dying species from Sardinia
No full textIn an environmental pollution research some wild
animals, deceased due to accidental causes, were collected
from all over Sardinia. In order to detect the possible
residues of unknown pollutants the isolated livers of
these animals, previously lyophilized, were analyzed.
First, by a GC-MS method, we identified the p,p'-DDE
and some PCBs belonging to 5, 6, 7, 8 series PCBs.
Later we set up a method for quantification of these
compounds, using chicken liver as a model, by GC-ECD.
The spiked chicken liver, free from p,p'-DDE and PCBs,
was lyophilized and extracted by supercritical fluid extraction
(SFE), subsequently the solutions obtained were
subjected to cleanup by solid phase extraction (SPE). Finally,
this method was employed to quantify p,p'-DDE
and PCBs in the samples of the specimens collected
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