Selective extraction of levoglucosan and its isomers from complex matrices using ligand exchange-solid phase extraction for analysis by liquid chromatography-electrospray ionization-tandem mass spectrometry.

The analysis of trace quantities of monosaccharide anhydrides (MAs) in sediments is complicated by the lack of fast and reliable technologies to selectively extract these water-soluble non-ionic compounds from samples of complex composition. Here we describe a solid phase extraction method that takes advantage of the affinity between monosaccharide anhydrides (MAs) and immobilized Na ions related to ligand-exchange processes (LE-SPE). The capacity factor of LE-SPE columns was enhanced by using non-aqueous mobile phases such as DCM/MeOH mixtures.

A new view on abrupt climate changes and the bipolar seesaw based on paleotemperatures from Iberian Margin sediments.

The last glacial cycle provides the opportunity to investigate large changes in the Atlantic Meridional Overturning Circulation (AMOC) beyond the small fluctuations evidenced from direct measurements. Paleotemperature records from Greenland and the North Atlantic show an abrupt variability, called Dansgaard-Oeschger (DO) events, which is associated with abrupt changes of the AMOC. These DO events also have Southern Hemisphere counterparts via the thermal bipolar seesaw, a concept describing the meridional heat transport leading to asynchronous temperature changes between both hemispheres.