Two young scientists – Karin Kipper and Riin Rebane – from UT analytical chemistry research group participated in the recent HPLC2013 conference in Amsterdam. Both of them presented the most recent results of their work.

The presentation of Karin Kipper (left) titled “Simultaneous Analysis of Carbapenems in Human Bodily Liquids Using HFIP as Buffer Additive in LC-ESI-MS/MS” focuses on the use of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as a weak volatile buffer acid for creating LC/ESI/MS mobile phases in the basic range (pH = 8 .. 10). It is not easy to find a good buffering system in this pH region that would at the same time be LC/MS compatible, that is, volatile and not suppressing inonization. HFIP, when mixed with ammonia, offers such possibility. Besides providing suitable buffering capacity at high pH HFIP as mobile phase component also increases the retention of compounds poorly retained on the C18 mobile phase and improves peak shape.

Riin Rebane (right) in her presentation “Method development strategy for derivatization LC/ESI/MS” explores the derivatizing agents for amino acids for LC/ESI/MS analysis. Amino acids generally cannot be analyzed by LC/ESI/MS without derivatization, because they are highly polar (zwitterionic) compounds and (1) are poorly separated on most stationary phases and (2) are (paradoxically!) poorly ionized in the ESI ion source. Riin has explored both classical (Fmoc-Cl, DNS, DEEMM) and novel (TAHS, FOSF) derivatization reagents. She discovered that the novel derivatization reagents proved to be more sensitive and the FOSF reagent (developed ans synthesized in her work) offered better chromatographic separation than TAHS. Moreover, with careful method development towards LC/ESI/MS analysis, classical reagent DEEMM can provide comparable detection to novel reagents with advantages such as good chromatographic separation and wide linear range.



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