Sassaki G.L.,Federal University of Parana |
Riter D.S.,Federal University of Parana |
Santana Filho A.P.,Federal University of Parana |
Guerrini M.,Istituto di Richerche Chimiche e Biochimiche G. Ronzoni |
And 11 more authors.
Analyst | Year: 2011
Recently, oversulfated chondroitin sulfate (OSCS) was identified in contaminated heparin preparations, which were linked to several adverse clinical events and deaths. Orthogonal analytical techniques, namely nuclear magnetic resonance (NMR) and capillary electrophoresis (CE), have since been applied by several authors for the evaluation of heparin purity and safety. NMR identification and quantification of residual solvents and non-volatile low molecular contaminants with USP acceptance levels of toxicity was achieved 40-fold faster than the traditional GC-headspace technique, which takes ∼120 min against ∼3 min to obtain a 1H NMR spectrum with a signal/noise ratio of at least 1000/1. The procedure allowed detection of Class 1 residual solvents at 2 ppm and quantification was possible above 10 ppm. 2D NMR techniques (edited-HSQC 1H/ 13C) permitted visualization of otherwise masked EDTA signals at 3.68/59.7 ppm and 3.34/53.5 ppm, which may be overlapping mononuclear heparin signals, or those of ethanol and methanol. Detailed NMR and ESI-MS/MS studies revealed a hitherto unknown contaminant, tris(2-n-butoxyethyl) phosphate (TBEP), which has potential health risks. © 2011 The Royal Society of Chemistry. Source