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Fast Screening (fast + screening)
Selected AbstractsSeparation of haemoglobin HbE and HbA2 by the fully automated, high-pressure liquid chromatography Tosoh HLC-723 G7 analyzerINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2008G. LIPPI Summary High-pressure liquid chromatography instruments specifically devised for separating haemoglobin (Hb) fractions have been increasingly employed by the hospital laboratories over the recent years since they allow easy and fast screening for several Hb variants. Although such instruments may be proposed as sensitive, specific and reliable alternatives to the classic electrophoretic techniques, a major drawback of this screening strategy is the almost identical retention time of several Hb variants. In particular, at least 18 Hb variants have been reported in the same retention window as HbA2, including HbE, the second most common ,-chain variant in humans after sickle cell trait. Recently, we evaluated the performance characteristics of an improved buffer formulation originally conceived for Hb variants separation procedures on the fully automated high-pressure liquid chromatography instrument Tosoh G7. At variance with other fully automated high-pressure liquid chromatography analyzers, the elution pattern on the G7 in subjects heterozygous for HbE is characterized by the presence of four suggestive peaks (HbF, HbA, HbA2 and HbE), confirming the effective separation of HbE from HbA2. Because of its potential value in the diagnosis of the thalassaemia syndromes, the effective separation of HbA2 from HbE can provide clinical laboratories with a valuable information for the diagnostic reasoning. [source] Direct exposure electron ionization mass spectrometry and gas chromatography/mass spectrometry techniques to study organic coatings on archaeological amphoraeJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 5 2005Maria Perla Colombini Abstract Two different analytical approaches, direct exposure electron ionization mass spectrometry (DE-MS) and gas chromatography/mass spectrometry (GC/MS), were compared in a study of archaeological resinous materials. DE-MS was found to be an efficient fingerprinting tool for the fast screening of organic archaeological samples and for providing information on the major components. GC/MS appeared to be more efficient in unravelling the sample composition at a molecular level, despite the long analysis time and the need for a wet chemical pretreatment. Both procedures were applied to characterize the organic material present as coatings in Roman and Egyptian amphorae. DE-MS successfully identified abietanic compounds, hence a diterpenic resinous material could be identified and its degree of oxidation assessed. GC/MS enabled us to identify dehydroabietic acid, 7-oxodehydroabietic acid, 15-hydroxy-7-oxodehydroabietic acid, 15-hydroxydehydroabietic acid, retene, tetrahydroretene, norabietatriene, norabietatetraene and methyl dehydroabietate. These oxidized and aromatized abietanes provided evidence that the amphorae examined were waterproofed with a pitch produced from resinous wood of plants from the Pinaceae family. The chemometric evaluation of the GC/MS data highlighted significant chemical differences between the pitches found in the two archaeological sites, basically related to differences in the production techniques of the materials and in their degradation pathways. Copyright © 2005 John Wiley & Sons, Ltd. [source] Shortcut method for kinetically controlled reactive distillation systemsAICHE JOURNAL, Issue 6 2003J. W. Lee A geometric-based shortcut method for reactive distillation is addressed. The rectification body method for nonreactive distillation, the concept of critical Damköhler numbers, and the geometric design method for reactive distillation are combined with a new eigenvector analysis of pinch points. This shortcut method provides a minimum or reasonable Damköhler number for a given heat duty, as well as the design implication of how to effectively distribute reaction zones inside a column. This method can be used for a fast screening of process design alternatives and for an initialization of rigorous optimization. [source] Investigation of relationships between barley stress peptides and beer gushing using SDS-PAGE and MS screeningJOURNAL OF SEPARATION SCIENCE, JSS, Issue 23-24 2009Blanka Hégrová Abstract The relationship between gushing and antifungal peptides in barley and malt kernels was examined for five barley varieties produced in the Czech Republic with four conditions of infection and treatment. Proteome changes during pathogen-seed interaction were observed with SDS-PAGE and MALDI-TOF MS. These methods were applied as a fast screening for observing the relationship between gushing and peptides/proteins. It was found that the presence of basic peptides, presumably hordothionins and non-specific lipid transfer protein type 1, did not correlate with the degree of gushing for malt (,r,,<0.07, 0.34>), (,r,,<0.01, 0.49>), respectively, as detected by both methods. [source] Electrospray-ionization mass spectrometry as a tool for fast screening of protein structural propertiesBIOTECHNOLOGY JOURNAL, Issue 1 2009Rita Grandori Abstract Since the early 1990s, electrospray-ionization mass spectrometry (ESI-MS) has encountered growing interest as a complementary tool to established biochemical and biophysical methods for investigating protein structure and conformation. Nowadays, applications of ESI-MS to protein investigation span from the area of analytical biochemistry to that of structural biology. This review focuses on applications of this technique to the analysis of protein conformational properties and molecular interactions, underscoring their possible relevance for molecular biotechnology, although representing a still very young field. An introductive section presents the major issues related to theoretical and technical aspects of ESI-MS under non-denaturing conditions. Examples from our work and from the literature illustrate which kind of information can be obtained concerning key issues in biotechnology such as stability and aggregation of proteins under both near-native and challenging conditions, and interactions with other proteins, ligands and cofactors. [source] | ||||||||||