Qualitative analysis of enzymatic and chemical depolymerized low molecular weight heparins by UHPLC coupled with electrospray ionization quadrupole time‐of‐flight‐mass spectrometry

Abstract

Complete heparin digestion with heparin lyase I and II results in a mixture of hexasaccharides and tetrasaccharides with 3‐O‐sulfo group‐containing glucosamine residues at their reducing ends. Because these tetrasaccharides are derived from antithrombin III‐binding sites of heparin, we examined whether this method could be applied to estimate the anticoagulant activity of heparin. Therefore, this paper presents a new low molecular weight heparin sample preparation method–chemical depolymerization. Qualitative analysis of the studied compounds and a comparison of their composition are an important contribution to the structural analysis of low molecular weight heparins, which has not been fully conducted so far. Qualitative on‐line liquid chromatography–mass spectrometric analysis of these resistant oligosaccharides is also described in this paper.

Diagnostic ion filtering targeted screening and isolation of anti‐inflammatory iridoid glycosides from Hedyotis diffusa

“…HPLC–QTOF‐MS/MS has been widely used for identification of bioactive compounds with high separation resolution, unambiguous precursor, and product ions information [1,4]. Nevertheless, produced massive MS data make manual annotation a rather tedious and difficult work [4].…”

“…HPLC–QTOF‐MS/MS has been widely used for identification of bioactive compounds with high separation resolution, unambiguous precursor, and product ions information [1,4]. Nevertheless, produced massive MS data make manual annotation a rather tedious and difficult work [4]. Recently, several MS/MS processing strategies have been developed to screen structural analogues, such as diagnostic product ion [4], neutral loss [5], mass defect filtering [6], and chemometrics [7] strategies.…”

“…Nevertheless, produced massive MS data make manual annotation a rather tedious and difficult work [4]. Recently, several MS/MS processing strategies have been developed to screen structural analogues, such as diagnostic product ion [4], neutral loss [5], mass defect filtering [6], and chemometrics [7] strategies. And different compounds, such as flavonoids, alkaloids, phenolic acids, and terpenoids, have been systematically analyzed by MS/MS processing methods [8,9].…”