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Microextraction in packed syringe (MEPS) is a new technique for miniaturised solid‐phase extraction that can be connected online to GC or LC. In this work, a liquid polymer was used as coating polymer on a filter in a 10 µL and 250 µL syringe to handle small sample volumes (≤10 µL plasma). Ropivacaine in plasma samples was used as model substance. The validation of the methodology showed that the accuracy values of quality control samples (QC) were in the range of 103%–114% for GC‐MS, and 98–101% for LC‐MS‐MS. The precisions, given as relative standard deviation (R.S.D.) were in the range 1.9 to11% for Inter‐ and intra‐day precisions. The standard curves were obtained within the concentration ranges 5‐2,000 nM in human plasma samples. The regression correlation coefficients (R 2 ) for plasma samples were 0.99 for all runs using GC‐MS and LC‐MS‐MS. [ABSTRACT FROM AUTHOR]

Polymeric tannins, extracted from grape berries (Gamay variety), were fractionated according to their mean degree of polymerisation (mDP) on a styrene-divinylbenzene phase eluted with a gradient of methanol:chloroform. Increasing the percentage of methanol led to the solubilisation of higher molecular weight tannins. The mean mDP of each collected fraction was determined by acid-catalysed degradation in the presence of a nucleophilic reagent. The fractionation method produced a linear gradient of mDP varying between 1.84 and 19.34. The fractions were partially characterised by matrix assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS). The spectra showed a complex mixture of proanthocyanidins and galloylated proanthocyanidins up to 4000 amu. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Electronic noses produce data which are difficult to transfer between identical instruments because of differences in the characteristics of "identical" instruments and because of sensor drift. The transportability of data is, however, essential for the setting up of databanks. Results of the present investigation, using processed cheeses and evaporated milk as reference materials, show that data transfer between two electronic noses based on mass spectrometry is possible and simple. [ABSTRACT FROM AUTHOR]

We have investigated the impacts of 63 different low-molecular-weight compounds, most of them plant derived, on the in vitro expression of two antifungal biosynthetic genes by the plant-protecting rhizobacterium Pseudomonas fluorescens CHA0. The majority of the compounds tested affected the expression of one or both antifungal genes. This suggests that biocontrol activity in plant-beneficial pseudomonads is modulated by plant-bacterium signaling. [ABSTRACT FROM AUTHOR]