The Experts below are selected from a list of 51 Experts worldwide ranked by ideXlab platform
Arianne Soliven - One of the best experts on this subject based on the ideXlab platform.
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a high throughput and high peak capacity narrow bore parallel segmented flow column strategy for the liquid chromatography tandem mass spectrometry analysis of organic contaminants in water
Analytical Methods, 2020Co-Authors: Arianne Soliven, Lucia Pareja, Andrew R Shalliker, Horacio Heinzen, Andres PerezparadaAbstract:This study highlights the development of a high peak capacity, high-throughput (HTP) approach for a target list of 62 organic contaminants in an environmental river water matrix on a HPLC conventional 400 bar system. Key Separation metrics were evaluated: (a) peak capacity, (b) total analysis time and (c) mobile phase consumption. An average peak width of 0.10 min with a total analysis time (inclusive of the column wash and re-equilibration) of 10 minutes revealed the increased productivity and performance of the parallel segmented flow (PSF) column technology HPLC-MS strategy, comparable to UHPLC peak widths and analysis times, achieved at a significantly lower backpressure (<400 bar). The operation of the PSF in a narrow-bore scale format (internal diameter of 2.1 mm) resulted in a conservative HPLC scale total mobile phase consumption of 15 mL for the column Separation; only 5.5 mL of this volume was exposed to the ion source per injection. Mobile phase consumption was higher compared to that of UHPLC, but on the other hand it achieved higher peak capacity. Three representative compounds (atrazine, diclofenac and fluazuron) with differing retention and ionisation properties were studied in detail in terms of detection sensitivity. The majority of the ion ratios for the standards in the river water matrix were within ±30% of the average ion ratios. The largest ion suppression occurred for atrazine (−25% matrix effect), a pesticide notorious for poor ionization and poor peak shape issues. The lowest response transitions at 1 μg L−1 for the extracted ions in the river water matrix of atrazine, diclofenac and fluazuron had signal to noise ratios ≥3, with the exception of diclofenac where 5 μg L−1 was the lowest calibration level. The peak area's calibration curve slope and standard deviation in the detector's response determination of limit of quantification (LOQ) were between 5.2 and 30.4 μg L−1.
Perez-parada Andres - One of the best experts on this subject based on the ideXlab platform.
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A high-throughput and high peak capacity narrow-bore parallel segmented flow column strategy for the liquid chromatography-tandem mass spectrometry analysis of organic contaminants in water
U.K. Royal Society of Chemistry, 2020Co-Authors: Solive Arianne, Pareja Lucia, Shalliker, Ross A., Heinze Horacio, Perez-parada AndresAbstract:This study highlights the development of a high peak capacity, high-throughput (HTP) approach for a target list of 62 organic contaminants in an environmental river water matrix on a HPLC conventional 400 bar system. Key Separation metrics were evaluated: (a) peak capacity, (b) total analysis time and (c) mobile phase consumption. An average peak width of 0.10 min with a total analysis time (inclusive of the column wash and re-equilibration) of 10 minutes revealed the increased productivity and performance of the parallel segmented flow (PSF) column technology HPLC-MS strategy, comparable to UHPLC peak widths and analysis times, achieved at a significantly lower backpressure (
Andres Perezparada - One of the best experts on this subject based on the ideXlab platform.
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a high throughput and high peak capacity narrow bore parallel segmented flow column strategy for the liquid chromatography tandem mass spectrometry analysis of organic contaminants in water
Analytical Methods, 2020Co-Authors: Arianne Soliven, Lucia Pareja, Andrew R Shalliker, Horacio Heinzen, Andres PerezparadaAbstract:This study highlights the development of a high peak capacity, high-throughput (HTP) approach for a target list of 62 organic contaminants in an environmental river water matrix on a HPLC conventional 400 bar system. Key Separation metrics were evaluated: (a) peak capacity, (b) total analysis time and (c) mobile phase consumption. An average peak width of 0.10 min with a total analysis time (inclusive of the column wash and re-equilibration) of 10 minutes revealed the increased productivity and performance of the parallel segmented flow (PSF) column technology HPLC-MS strategy, comparable to UHPLC peak widths and analysis times, achieved at a significantly lower backpressure (<400 bar). The operation of the PSF in a narrow-bore scale format (internal diameter of 2.1 mm) resulted in a conservative HPLC scale total mobile phase consumption of 15 mL for the column Separation; only 5.5 mL of this volume was exposed to the ion source per injection. Mobile phase consumption was higher compared to that of UHPLC, but on the other hand it achieved higher peak capacity. Three representative compounds (atrazine, diclofenac and fluazuron) with differing retention and ionisation properties were studied in detail in terms of detection sensitivity. The majority of the ion ratios for the standards in the river water matrix were within ±30% of the average ion ratios. The largest ion suppression occurred for atrazine (−25% matrix effect), a pesticide notorious for poor ionization and poor peak shape issues. The lowest response transitions at 1 μg L−1 for the extracted ions in the river water matrix of atrazine, diclofenac and fluazuron had signal to noise ratios ≥3, with the exception of diclofenac where 5 μg L−1 was the lowest calibration level. The peak area's calibration curve slope and standard deviation in the detector's response determination of limit of quantification (LOQ) were between 5.2 and 30.4 μg L−1.
Solive Arianne - One of the best experts on this subject based on the ideXlab platform.
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A high-throughput and high peak capacity narrow-bore parallel segmented flow column strategy for the liquid chromatography-tandem mass spectrometry analysis of organic contaminants in water
U.K. Royal Society of Chemistry, 2020Co-Authors: Solive Arianne, Pareja Lucia, Shalliker, Ross A., Heinze Horacio, Perez-parada AndresAbstract:This study highlights the development of a high peak capacity, high-throughput (HTP) approach for a target list of 62 organic contaminants in an environmental river water matrix on a HPLC conventional 400 bar system. Key Separation metrics were evaluated: (a) peak capacity, (b) total analysis time and (c) mobile phase consumption. An average peak width of 0.10 min with a total analysis time (inclusive of the column wash and re-equilibration) of 10 minutes revealed the increased productivity and performance of the parallel segmented flow (PSF) column technology HPLC-MS strategy, comparable to UHPLC peak widths and analysis times, achieved at a significantly lower backpressure (
Svein J. Knapskog - One of the best experts on this subject based on the ideXlab platform.
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on the importance of the Key Separation principle for different modes of operation
Information Security Practice and Experience, 2008Co-Authors: Danilo Gligoroski, Suzana Andova, Svein J. KnapskogAbstract:The Key Separation principle for different modes of operation of the block ciphers is a cryptographic folklore wisdom that states: One should always use distinct Keys for distinct algorithms and distinct modes of operation. If this principle is violated, then there are generic attacks that can recover the whole or a part of the encrypted messages. By the advent of software packages and libraries that offer some or all modes of operation of block ciphers, the violation of this principle is really possible in practice. We show that under the same Key, OFB mode of operation is a special case of the CBC mode of operation, and that if CBC and CTR modes of operation are interchangeably used under the same secret Key - then the security of the encryption process is seriously weakened. Moreover in the chosen plaintext attack scenario with interchanged use of CBC and OFB mode under the same Key, we give a concrete list of openssl commands that can extract the complete plaintext without knowing the secret Key.
