Rapid Characterization (rapid + characterization)

Distribution by Scientific Domains

Selected Abstracts

Rapid Characterization of Complex Viscous Liquids at the Molecular Level,

Siang Law
Klebrige Objekte: Ein N2 -Strom liefert in viskosen Flüssigkeiten Bläschen, die durch Mikrostrahlbildung eine Aerosolprobe erzeugen (siehe Bild). Dieses Aerosol wird anschließend durch extrahierende Elektrosprayionisations-Massenspektrometrie (EESI-MS) analysiert. EESI-MS enthüllt die molekulare Zusammensetzung komplexer Flüssigkeiten und die Kinetik von Prozessen in den hoch viskosen Flüssigkeiten ohne jegliche Probenvorbehandlung. [source]

Rapid characterization of fatty alcohol ethoxylates by non-aqueous capillary electrophoresis

Mónica Arias
Abstract Fatty alcohol ethoxylates (FAE) (a mixture of nonionic surfactants) have been characterized using NACE with UV detection. Phenyl polyurethane derivatives of these compounds were previously obtained by reaction with phenyl isocyanate. The derivatization reaction only requires microwave irradiation for 30,s (600,W). Phenyl polyurethanes were separated and characterized using a BGE containing a mixture of ammonium nitrate (15,mM), acetic acid (1.5%) and 9:1 v/v methanol/ACN. After optimization of the instrumental conditions for the separation, phenyl polyurethane compounds (formed from the corresponding FAE) with ethylene oxide numbers (EON) of 6 (certified standard and industrial samples), 7 and 10 (both as industrial samples), and 5.5 (microemulsion phase) were successfully separated and characterized. The properties of these FAE nonionic surfactants are very important in the petroleum industry, which requires characterization of the quality of the purchased materials as well as the final products in the microemulsion-oil-water stream process. This analytical objective has been achieved by the proposed NACE methods, allowing FAE to be distinguished from 5.5 to 10 EON with errors below 4%, and shows advantages against to HPLC methods. [source]

Rapid characterization of edible oils by direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis using triacylglycerols

Jackson O. Lay Jr.
Direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOFMS) analysis of solutions of edible fats/oils yielded spectra useful for their rapid differentiation and classification. Results also reflected the individual fatty acid components and their degree of unsaturation. After dissolution in hexane, MALDI-MS analysis revealed spectra showing characteristic triacylglycerols (TAGs), the main fat/oil components, as sodium adduct ions. The Euclidean distances calculated using the mass and intensity values for 20 TAGs were used to evaluate and compare spectra. With cluster analysis, animal fats grouped together differently than vegetable oils and the individual oils grouped together by type. The ion abundances for the individual TAGs and their presumed compositions were used to approximate the overall fatty acid composition of canola, soybean, corn, olive and peanut oil, as well as lard. Using this approach the calculated fatty acid compositions and degree of unsaturation generally fell within about 4% of literature values. When the degree of saturation was compared with values calculated from the package labeling the differences were about 7%. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Rapid characterization and quality control of complex cell culture media solutions using raman spectroscopy and chemometrics

Boyan Li
Abstract The use of Raman spectroscopy coupled with chemometrics for the rapid identification, characterization, and quality assessment of complex cell culture media components used for industrial mammalian cell culture was investigated. Raman spectroscopy offers significant advantages for the analysis of complex, aqueous-based materials used in biotechnology because there is no need for sample preparation and water is a weak Raman scatterer. We demonstrate the efficacy of the method for the routine analysis of dilute aqueous solution of five different chemically defined (CD) commercial media components used in a Chinese Hamster Ovary (CHO) cell manufacturing process for recombinant proteins. The chemometric processing of the Raman spectral data is the key factor in developing robust methods. Here, we discuss the optimum methods for eliminating baseline drift, background fluctuations, and other instrumentation artifacts to generate reproducible spectral data. Principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA) were then employed in the development of a robust routine for both identification and quality evaluation of the five different media components. These methods have the potential to be extremely useful in an industrial context for "in-house" sample handling, tracking, and quality control. Biotechnol. Bioeng. 2010;107: 290,301. © 2010 Wiley Periodicals, Inc. [source]