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Felix Hernandez - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of acidic neutral and basic pharmaceuticals in urban wastewater by ultra high pressure Liquid Chromatography tandem mass spectrometry
Journal of Chromatography A, 2010Co-Authors: Emma Gracialor, Juan V Sancho, Felix HernandezAbstract:In this work, an ultra High-Pressure Liquid Chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the simultaneous quantification and confirmation of the 20 most consumed pharmaceuticals in Spain in urban wastewater and surface water samples. The scope of the method included acidic, neutral and basic compounds belonging to different therapeutic classes and allows their simultaneous determination in just a single injection, giving realistic information of the most widely consumed pharmaceuticals in only one analysis. An enrichment step based on solid-phase extraction using Oasis HLB cartridges was carried out, followed by UHPLC-MS/MS measurement with a fast-acquisition triple quadrupole mass analyzer. It allowed working with short dwell times and made possible to acquire three simultaneous SRM transitions per compound to assure a reliable identification. Several isotope-labelled internal standards were used as surrogates to correct SPE losses, as well as matrix effects that notably affect quantification of analytes. The method was validated in surface water and effluent and influent urban wastewater at different concentrations from 0.005microg/L (surface water) to 1.25microg/L (influent wastewater). The optimized method was applied to the analysis of 84 urban wastewater samples (influent and effluent), with the result that 17 out of 20 compounds monitored were detected in the samples. Analgesics and anti-inflamatories, cholesterol lowering statin drugs and lipid regulators were the major groups found, with diclofenac, ketoprofen, naproxen, 4-aminoantipyrine, bezafibrate, gemfibrozil and venlafaxine being the most frequently detected. The highest concentration level reached was 277microg/L for salicylic acid in influent wastewater.
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determination of mycotoxins in different food commodities by ultra high pressure Liquid Chromatography coupled to triple quadrupole mass spectrometry
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Eduardo Beltran, Juan V Sancho, Maria Ibanez, Felix HernandezAbstract:A rapid multianalyte-multiclass method with little sample manipulation has been developed for the simultaneous determination of eleven mycotoxins in different food commodities by using ultra-High-Pressure Liquid Chromatography coupled to triple quadrupole mass spectrometry (UHPLC/MS/MS). Toxins were extracted from the samples with acetonitrile/water (80:20, v/v) 0.1% HCOOH and, after a two-fold dilution with water, directly injected into the system. Thanks to the fast high-resolution separation of UHPLC, the eleven mycotoxins were separated by gradient elution in only 4 min. The method has been validated in three food matrices (maize kernels, dry pasta (wheat), and eight-multicereal babyfood (wheat, maize, rice, oat, barley, rye, sorghum, millet)) at four different concentration levels. Satisfactory recoveries were obtained (70–110%) and precision (expressed as relative standard deviation) was typically below 15% with very few exceptions. Quantification of samples was carried out with matrix-matched standards calibration. The lowest concentration successfully validated in sample was as low as 0.5 µg/kg for aflatoxins and ochratoxin A in babyfood, and 20 µg/kg for the rest of the selected mycotoxins in all matrices tested. Deoxynivalenol could be only validated at 200 µg/kg, due the poor sensitivity for this mycotoxin analysis. With only two exceptions (HT-2 and deoxynivalenol), the limits of detection (LODs), estimated for a signal-to-noise ratio of 3 from the chromatograms of samples spiked at the lowest level validated, varied between 0.1 and 1 µg/kg in the three food matrices tested. The method was applied to the analysis of different kinds of samples. Positive findings were confirmed by acquiring two transitions (Q quantification, q confirmation) and evaluating the Q/q ratio. Copyright © 2009 John Wiley & Sons, Ltd.
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determination of mycotoxins in different food commodities by ultra high pressure Liquid Chromatography coupled to triple quadrupole mass spectrometry
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Eduardo Beltran, Juan V Sancho, Maria Ibanez, Felix HernandezAbstract:A rapid multianalyte-multiclass method with little sample manipulation has been developed for the simultaneous determination of eleven mycotoxins in different food commodities by using ultra-High-Pressure Liquid Chromatography coupled to triple quadrupole mass spectrometry (UHPLC/MS/MS). Toxins were extracted from the samples with acetonitrile/water (80:20, v/v) 0.1% HCOOH and, after a two-fold dilution with water, directly injected into the system. Thanks to the fast high-resolution separation of UHPLC, the eleven mycotoxins were separated by gradient elution in only 4 min. The method has been validated in three food matrices (maize kernels, dry pasta (wheat), and eight-multicereal babyfood (wheat, maize, rice, oat, barley, rye, sorghum, millet)) at four different concentration levels. Satisfactory recoveries were obtained (70-110%) and precision (expressed as relative standard deviation) was typically below 15% with very few exceptions. Quantification of samples was carried out with matrix-matched standards calibration. The lowest concentration successfully validated in sample was as low as 0.5 microg/kg for aflatoxins and ochratoxin A in babyfood, and 20 microg/kg for the rest of the selected mycotoxins in all matrices tested. Deoxynivalenol could be only validated at 200 microg/kg, due the poor sensitivity for this mycotoxin analysis. With only two exceptions (HT-2 and deoxynivalenol), the limits of detection (LODs), estimated for a signal-to-noise ratio of 3 from the chromatograms of samples spiked at the lowest level validated, varied between 0.1 and 1 microg/kg in the three food matrices tested. The method was applied to the analysis of different kinds of samples. Positive findings were confirmed by acquiring two transitions (Q quantification, q confirmation) and evaluating the Q/q ratio.
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simultaneous ultra high pressure Liquid Chromatography tandem mass spectrometry determination of amphetamine and amphetamine like stimulants cocaine and its metabolites and a cannabis metabolite in surface water and urban wastewater
Journal of Chromatography A, 2009Co-Authors: Lubertus Bijlsma, Juan V Sancho, E Pitarch, Maria Ibanez, Felix HernandezAbstract:Abstract An ultra-High-Pressure Liquid Chromatography–tandem mass spectrometry (UHPLC–MS/MS) method has been developed for the simultaneous quantification and confirmation of 11 basic/acidic illicit drugs and relevant metabolites in surface and urban wastewater at ng/L levels. The sample pre-treatment consisted of a solid-phase extraction using Oasis MCX cartridges. Analyte deuterated compounds were used as surrogate internal standards (except for norbenzoylecgonine and norcocaine) to compensate for possible errors resulting from matrix effects and those associated to the sample preparation procedure. After SPE enrichment, the selected drugs were separated within 6 min under UHPLC optimized conditions. To efficiently combine UHPLC with MS/MS, a fast-acquisition triple quadrupole mass analyzer (TQD from Waters) in positive-ion mode (ESI+) was used. The excellent selectivity and sensitivity of the TQD analyzer in selected reaction monitoring mode allowed quantification and reliable identification at the LOQ levels. Satisfactory recoveries (70–120%) and precision (RSD 99%) for low levels of illicit drugs in water, but some difficulties were observed when high drug levels were present in wastewaters.
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screening of antibiotics in surface and wastewater samples by ultra high pressure Liquid Chromatography coupled to hybrid quadrupole time of flight mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Maria Ibanez, Juan V Sancho, Carlos Guerrero, Felix HernandezAbstract:Abstract The potential of ultra-High-Pressure Liquid Chromatography (UHPLC) coupled to hybrid quadrupole time-of-flight mass spectrometry (QTOF–MS) for the screening and confirmation of antibiotics in water samples is illustrated in this paper. UHPLC presents several advantages over conventional Liquid Chromatography as it generates narrow peaks (increasing peak height and improving sensitivity) and reduces chromatographic runs. Regarding QTOF–MS, its increased mass resolution, high sensitivity in full-spectrum acquisition mode and mass accuracy, in both MS and MS/MS modes, make this technique ideal for the detection and reliable confirmation of organic contaminants in environmental samples. After a solid-phase extraction using Oasis HLB cartridges, UHPLC–QTOF–MS has been applied in this work to several types of water samples (surface water and influent and effluent wastewaters). Several antibiotics were found in the samples, such as ofloxacin, ciprofloxacin, clarythromycin or erythromycin, among others. Moreover, the full spectrum data provided by TOF–MS acquisition has enabled searching for many other pharmaceuticals that could be present in the samples in a “post-target” way. This approach has allowed the detection and confirmation of paracetamol, omeprazole and codeine, among others. UPLC–QTOF–MS has been shown as an attractive and efficient hyphenated technique for the rapid detection and confirmation of pharmaceuticals in water with very little sample handling.
Serge Rudaz - One of the best experts on this subject based on the ideXlab platform.
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ultra high pressure Liquid Chromatography for crude plant extract profiling
Journal of AOAC International, 2011Co-Authors: Philippe J Eugster, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Jean-luc WolfenderAbstract:Ultra high pressure Liquid Chromatography (UHPLC) systems operating at very high pressures and using sub-2 μm packing columns have allowed a remarkable decrease in analysis time and increase in peak capacity, sensitivity, and reproducibility compared to conventional HPLC. This technology has rapidly been widely accepted by the analytical community and is being gradually applied to various fields of plant analysis such as QC, profiling and fingerprinting, dereplication, and metabolomics. For many applications, an important improvement of the overall performances has been reported. In this review, the basic principles of UHPLC are summarized, and practical information on the type of columns used and phase chemistry available is provided. An overview of the latest applications to natural product analysis in complex mixtures is given, and the potential and limitations as well as some new trends in the development of UHPLC are discussed.
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fast analysis of doping agents in urine by ultra high pressure Liquid Chromatography quadrupole time of flight mass spectrometry ii confirmatory analysis
Journal of Chromatography A, 2010Co-Authors: Flavia Badoud, Serge Rudaz, Martial Saugy, Elia Grata, L PerrenoudAbstract:The general strategy to perform anti-doping analyses of urine samples starts with the screening for a wide range of compounds. This step should be fast, generic and able to detect any sample that may contain a prohibited substance while avoiding false negatives and reducing false positive results. The experiments presented in this work were based on ultra-High-Pressure Liquid Chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry. Thanks to the high sensitivity of the method, urine samples could be diluted 2-fold prior to injection. One hundred and three forbidden substances from various classes (such as stimulants, diuretics, narcotics, anti-estrogens) were analysed on a C(18) reversed-phase column in two gradients of 9min (including two 3min equilibration periods) for positive and negative electrospray ionisation and detected in the MS full scan mode. The automatic identification of analytes was based on retention time and mass accuracy, with an automated tool for peak picking. The method was validated according to the International Standard for Laboratories described in the World Anti-Doping Code and was selective enough to comply with the World Anti-Doping Agency recommendations. In addition, the matrix effect on MS response was measured on all investigated analytes spiked in urine samples. The limits of detection ranged from 1 to 500ng/mL, allowing the identification of all tested compounds in urine. When a sample was reported positive during the screening, a fast additional pre-confirmatory step was performed to reduce the number of confirmatory analyses.
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coupling ultra high pressure Liquid Chromatography with mass spectrometry
Trends in Analytical Chemistry, 2010Co-Authors: Davy Guillarme, Julie Schappler, Serge Rudaz, Jeanluc VeutheyAbstract:Abstract In recent years, different approaches have been taken to improve chromatographic performance in terms of analysis time and/or resolution. The use of columns packed with sub-2μm particles in ultra-High-Pressure Liquid Chromatography (UHPLC) has become a technique of choice in many laboratories. Furthermore, for the analysis of complex matrices (e.g., biological fluids, plant extracts, and food and environmental samples), coupling UHPLC with mass spectrometry (MS) or tandem MS (MS 2 ) provides a powerful analytical tool. This review describes major advances in the field of UHPLC-MS and UHPLC-MS 2 . We strongly emphasize the possibility of speeding up bioanalysis, drug metabolism, and multi-residue screening assays, while maintaining qualitative and quantitative performance equivalent to HPLC-MS and HPLC-MS 2 . We also report the possibility of gaining additional information in metabolomics, using high-resolution UHPLC with a time-of-flight analyzer. The studies summarized are discussed in this review in terms of throughput increases and resolution enhancements afforded by UHPLC. In addition, we highlight the impact of UHPLC conditions on MS detection capabilities (e.g., acquisition rate, limits of detection and matrix effects).
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Fast log P determination by ultra-High-Pressure Liquid Chromatography coupled with UV and mass spectrometry detections
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Yveline Henchoz, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Sophie Martel, Pierrealain CarruptAbstract:Ultra-High-Pressure Liquid Chromatography (UHPLC) systems able to work with columns packed with sub-2 μm particles offer very fast methods to determine the lipophilicity of new chemical entities. The careful development of the most suitable experimental conditions presented here will help medicinal chemists for high-throughput screening (HTS) log P _oct measurements. The approach was optimized using a well-balanced set of 38 model compounds and a series of 28 basic compounds such as β-blockers, local anesthetics, piperazines, clonidine, and derivatives. Different organic modifiers and hybrid stationary phases packed with 1.7-μm particles were evaluated in isocratic as well as gradient modes, and the advantages and limitations of tested conditions pointed out. The UHPLC approach offered a significant enhancement over the classical HPLC methods, by a factor 50 in the lipophilicity determination throughput. The hyphenation of UHPLC with MS detection allowed a further increase in the throughput. Data and results reported herein prove that the UHPLC-MS method can represent a progress in the HTS-measurement of lipophilicity due to its speed (at least a factor of 500 with respect to HPLC approaches) and to an extended field of application. Figure The UHPLC approach described here greatly enhanced the time required for log P determination (5' min by compound using UV detection) and, at least, 8 compounds measured in a 5' run when Mass Spectrometry detection in used. These developments offer to medicinal chemists a high-throughput method to estimate the lipophilicity of NCEs
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metabolite profiling of plant extracts by ultra high pressure Liquid Chromatography at elevated temperature coupled to time of flight mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Elia Grata, Gaétan Glauser, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Julien Boccard, Jean-luc WolfenderAbstract:Detailed metabolite profiling of crude plant extracts, mandatory for both quality control and metabolomics purposes, requires high-resolution separation and sensitive detection with a reasonable sample throughput. In this respect, the use of ultra-High-Pressure Liquid Chromatography (UHPLC) working at high temperature (HT) and coupled to time-of-flight mass spectrometry (TOF-MS) was evaluated in the present study in terms of achievable peak capacities for given analysis times. Prior to the analysis of complex mixtures, the effects of TOF-MS detection on peak capacity were evaluated, and a loss of 15-30% compared to UV was observed due to the additional band broadening generated by this detector. Extracts from a model plant Arabidopsis thaliana and from a widely used phytochemical preparation Ginkgo biloba, as well as a standard mixture of representative natural products (NPs), have been analyzed. As expected from the theory, the increase in mobile phase temperature of up to 90 degrees C for the profiling of extracts containing metabolites spread over a large polarity range (e.g., Arabidopsis thaliana) generated similar peak capacities to those obtained at room temperature, but with a 2- to 3-fold reduction in analysis time, demonstrating the power of this approach for such applications. On the other hand, for the analysis of more polar extracts (e.g., Ginkgo biloba), the use of higher temperature was not beneficial, as it induced a significant decrease in retention, and thus resolving power, because of the increase in elution strength. The use of HT-UHPLC-TOF-MS raised the question of NP stability under high temperature conditions. This work demonstrated that no apparent degradation was evidenced at high temperature for a representative mixture of NPs and also for the different metabolites detected in the selected plant extracts.
Elia Grata - One of the best experts on this subject based on the ideXlab platform.
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fast analysis of doping agents in urine by ultra high pressure Liquid Chromatography quadrupole time of flight mass spectrometry ii confirmatory analysis
Journal of Chromatography A, 2010Co-Authors: Flavia Badoud, Serge Rudaz, Martial Saugy, Elia Grata, L PerrenoudAbstract:The general strategy to perform anti-doping analyses of urine samples starts with the screening for a wide range of compounds. This step should be fast, generic and able to detect any sample that may contain a prohibited substance while avoiding false negatives and reducing false positive results. The experiments presented in this work were based on ultra-High-Pressure Liquid Chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry. Thanks to the high sensitivity of the method, urine samples could be diluted 2-fold prior to injection. One hundred and three forbidden substances from various classes (such as stimulants, diuretics, narcotics, anti-estrogens) were analysed on a C(18) reversed-phase column in two gradients of 9min (including two 3min equilibration periods) for positive and negative electrospray ionisation and detected in the MS full scan mode. The automatic identification of analytes was based on retention time and mass accuracy, with an automated tool for peak picking. The method was validated according to the International Standard for Laboratories described in the World Anti-Doping Code and was selective enough to comply with the World Anti-Doping Agency recommendations. In addition, the matrix effect on MS response was measured on all investigated analytes spiked in urine samples. The limits of detection ranged from 1 to 500ng/mL, allowing the identification of all tested compounds in urine. When a sample was reported positive during the screening, a fast additional pre-confirmatory step was performed to reduce the number of confirmatory analyses.
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metabolite profiling of plant extracts by ultra high pressure Liquid Chromatography at elevated temperature coupled to time of flight mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Elia Grata, Gaétan Glauser, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Julien Boccard, Jean-luc WolfenderAbstract:Detailed metabolite profiling of crude plant extracts, mandatory for both quality control and metabolomics purposes, requires high-resolution separation and sensitive detection with a reasonable sample throughput. In this respect, the use of ultra-High-Pressure Liquid Chromatography (UHPLC) working at high temperature (HT) and coupled to time-of-flight mass spectrometry (TOF-MS) was evaluated in the present study in terms of achievable peak capacities for given analysis times. Prior to the analysis of complex mixtures, the effects of TOF-MS detection on peak capacity were evaluated, and a loss of 15-30% compared to UV was observed due to the additional band broadening generated by this detector. Extracts from a model plant Arabidopsis thaliana and from a widely used phytochemical preparation Ginkgo biloba, as well as a standard mixture of representative natural products (NPs), have been analyzed. As expected from the theory, the increase in mobile phase temperature of up to 90 degrees C for the profiling of extracts containing metabolites spread over a large polarity range (e.g., Arabidopsis thaliana) generated similar peak capacities to those obtained at room temperature, but with a 2- to 3-fold reduction in analysis time, demonstrating the power of this approach for such applications. On the other hand, for the analysis of more polar extracts (e.g., Ginkgo biloba), the use of higher temperature was not beneficial, as it induced a significant decrease in retention, and thus resolving power, because of the increase in elution strength. The use of HT-UHPLC-TOF-MS raised the question of NP stability under high temperature conditions. This work demonstrated that no apparent degradation was evidenced at high temperature for a representative mixture of NPs and also for the different metabolites detected in the selected plant extracts.
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metabolite profiling of plant extracts by ultra high pressure Liquid Chromatography at elevated temperature coupled to time of flight mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Elia Grata, Gaétan Glauser, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Julien Boccard, Jean-luc WolfenderAbstract:Abstract Detailed metabolite profiling of crude plant extracts, mandatory for both quality control and metabolomics purposes, requires high-resolution separation and sensitive detection with a reasonable sample throughput. In this respect, the use of ultra-High-Pressure Liquid Chromatography (UHPLC) working at high temperature (HT) and coupled to time-of-flight mass spectrometry (TOF-MS) was evaluated in the present study in terms of achievable peak capacities for given analysis times. Prior to the analysis of complex mixtures, the effects of TOF-MS detection on peak capacity were evaluated, and a loss of 15–30% compared to UV was observed due to the additional band broadening generated by this detector. Extracts from a model plant Arabidopsis thaliana and from a widely used phytochemical preparation Ginkgo biloba, as well as a standard mixture of representative natural products (NPs), have been analyzed. As expected from the theory, the increase in mobile phase temperature of up to 90 °C for the profiling of extracts containing metabolites spread over a large polarity range (e.g., Arabidopsis thaliana) generated similar peak capacities to those obtained at room temperature, but with a 2- to 3-fold reduction in analysis time, demonstrating the power of this approach for such applications. On the other hand, for the analysis of more polar extracts (e.g., Ginkgo biloba), the use of higher temperature was not beneficial, as it induced a significant decrease in retention, and thus resolving power, because of the increase in elution strength. The use of HT-UHPLC–TOF-MS raised the question of NP stability under high temperature conditions. This work demonstrated that no apparent degradation was evidenced at high temperature for a representative mixture of NPs and also for the different metabolites detected in the selected plant extracts.
Ira S Lurie - One of the best experts on this subject based on the ideXlab platform.
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use of multiple reaction monitoring ratios for identifying incompletely resolved fentanyl homologs and analogs via ultra high pressure Liquid Chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Ira S LurieAbstract:Abstract Fentanyl and 16 of its corresponding homologs and analogs were distinguished using ultra-High-Pressure Liquid Chromatography–tandem mass spectrometry (UHPLC–MS/MS). A 1.7 μm Acquity BEH C18 column (150 mm × 2.1 mm) was used with a 1% formic acid (pH 2.2), methanol gradient. Multiple-reaction monitoring (MRM) was employed for MS/MS detection. All selected fentanyl-related compounds, including incompletely resolved compounds, were uniquely identified using retention times and dual MRMs.
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use of multiple reaction monitoring ratios for identifying incompletely resolved fentanyl homologs and analogs via ultra high pressure Liquid Chromatography tandem mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Ira S LurieAbstract:Abstract Fentanyl and 16 of its corresponding homologs and analogs were distinguished using ultra-High-Pressure Liquid Chromatography–tandem mass spectrometry (UHPLC–MS/MS). A 1.7 μm Acquity BEH C18 column (150 mm × 2.1 mm) was used with a 1% formic acid (pH 2.2), methanol gradient. Multiple-reaction monitoring (MRM) was employed for MS/MS detection. All selected fentanyl-related compounds, including incompletely resolved compounds, were uniquely identified using retention times and dual MRMs.
Davy Guillarme - One of the best experts on this subject based on the ideXlab platform.
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coupling ultra high pressure Liquid Chromatography with mass spectrometry constraints and possible applications
Journal of Chromatography A, 2013Co-Authors: Marta Rodriguezaller, Jeanluc Veuthey, Robert Gurny, Davy GuillarmeAbstract:The introduction of columns packed with porous sub-2μm particles and the extension of the upper pressure limit of HPLC instrumentation to 1300bar (ultra-high pressure Liquid Chromatography, UHPLC) has opened new frontiers in resolution and speed of analysis. However, certain constraints appear when coupling UHPLC technology with mass spectrometry (MS). First, the most significant limitation is related to the narrow peaks that are produced by UHPLC that require a fast duty cycle, which is only available on the latest generations of MS devices. Thus, certain analyzers are more readily compatible with UHPLC (e.g., QqQ or TOF/MS) than others (e.g., ion trap or FT-MS). Second, due to the reduction of the column volume, extra-column band broadening can become significant, leading to a reduction in the kinetic performance of the UHPLC-MS configuration. Third, as the mobile phase linear velocity is higher in UHPLC, the electrospray ionization source must also be able to provide high sensitivity at flow rates of up to 1mL/min. Despite these limitations, the UHPLC-MS/MS platform has successfully been employed over the last decade for various types of applications, including those related to bioanalysis, drug metabolism, multi-residue screening, metabolomics, biopharmaceuticals and polar compounds.
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ultra high pressure Liquid Chromatography for crude plant extract profiling
Journal of AOAC International, 2011Co-Authors: Philippe J Eugster, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Jean-luc WolfenderAbstract:Ultra high pressure Liquid Chromatography (UHPLC) systems operating at very high pressures and using sub-2 μm packing columns have allowed a remarkable decrease in analysis time and increase in peak capacity, sensitivity, and reproducibility compared to conventional HPLC. This technology has rapidly been widely accepted by the analytical community and is being gradually applied to various fields of plant analysis such as QC, profiling and fingerprinting, dereplication, and metabolomics. For many applications, an important improvement of the overall performances has been reported. In this review, the basic principles of UHPLC are summarized, and practical information on the type of columns used and phase chemistry available is provided. An overview of the latest applications to natural product analysis in complex mixtures is given, and the potential and limitations as well as some new trends in the development of UHPLC are discussed.
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coupling ultra high pressure Liquid Chromatography with mass spectrometry
Trends in Analytical Chemistry, 2010Co-Authors: Davy Guillarme, Julie Schappler, Serge Rudaz, Jeanluc VeutheyAbstract:Abstract In recent years, different approaches have been taken to improve chromatographic performance in terms of analysis time and/or resolution. The use of columns packed with sub-2μm particles in ultra-High-Pressure Liquid Chromatography (UHPLC) has become a technique of choice in many laboratories. Furthermore, for the analysis of complex matrices (e.g., biological fluids, plant extracts, and food and environmental samples), coupling UHPLC with mass spectrometry (MS) or tandem MS (MS 2 ) provides a powerful analytical tool. This review describes major advances in the field of UHPLC-MS and UHPLC-MS 2 . We strongly emphasize the possibility of speeding up bioanalysis, drug metabolism, and multi-residue screening assays, while maintaining qualitative and quantitative performance equivalent to HPLC-MS and HPLC-MS 2 . We also report the possibility of gaining additional information in metabolomics, using high-resolution UHPLC with a time-of-flight analyzer. The studies summarized are discussed in this review in terms of throughput increases and resolution enhancements afforded by UHPLC. In addition, we highlight the impact of UHPLC conditions on MS detection capabilities (e.g., acquisition rate, limits of detection and matrix effects).
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Fast log P determination by ultra-High-Pressure Liquid Chromatography coupled with UV and mass spectrometry detections
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Yveline Henchoz, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Sophie Martel, Pierrealain CarruptAbstract:Ultra-High-Pressure Liquid Chromatography (UHPLC) systems able to work with columns packed with sub-2 μm particles offer very fast methods to determine the lipophilicity of new chemical entities. The careful development of the most suitable experimental conditions presented here will help medicinal chemists for high-throughput screening (HTS) log P _oct measurements. The approach was optimized using a well-balanced set of 38 model compounds and a series of 28 basic compounds such as β-blockers, local anesthetics, piperazines, clonidine, and derivatives. Different organic modifiers and hybrid stationary phases packed with 1.7-μm particles were evaluated in isocratic as well as gradient modes, and the advantages and limitations of tested conditions pointed out. The UHPLC approach offered a significant enhancement over the classical HPLC methods, by a factor 50 in the lipophilicity determination throughput. The hyphenation of UHPLC with MS detection allowed a further increase in the throughput. Data and results reported herein prove that the UHPLC-MS method can represent a progress in the HTS-measurement of lipophilicity due to its speed (at least a factor of 500 with respect to HPLC approaches) and to an extended field of application. Figure The UHPLC approach described here greatly enhanced the time required for log P determination (5' min by compound using UV detection) and, at least, 8 compounds measured in a 5' run when Mass Spectrometry detection in used. These developments offer to medicinal chemists a high-throughput method to estimate the lipophilicity of NCEs
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metabolite profiling of plant extracts by ultra high pressure Liquid Chromatography at elevated temperature coupled to time of flight mass spectrometry
Journal of Chromatography A, 2009Co-Authors: Elia Grata, Gaétan Glauser, Serge Rudaz, Jeanluc Veuthey, Davy Guillarme, Pierrealain Carrupt, Julien Boccard, Jean-luc WolfenderAbstract:Detailed metabolite profiling of crude plant extracts, mandatory for both quality control and metabolomics purposes, requires high-resolution separation and sensitive detection with a reasonable sample throughput. In this respect, the use of ultra-High-Pressure Liquid Chromatography (UHPLC) working at high temperature (HT) and coupled to time-of-flight mass spectrometry (TOF-MS) was evaluated in the present study in terms of achievable peak capacities for given analysis times. Prior to the analysis of complex mixtures, the effects of TOF-MS detection on peak capacity were evaluated, and a loss of 15-30% compared to UV was observed due to the additional band broadening generated by this detector. Extracts from a model plant Arabidopsis thaliana and from a widely used phytochemical preparation Ginkgo biloba, as well as a standard mixture of representative natural products (NPs), have been analyzed. As expected from the theory, the increase in mobile phase temperature of up to 90 degrees C for the profiling of extracts containing metabolites spread over a large polarity range (e.g., Arabidopsis thaliana) generated similar peak capacities to those obtained at room temperature, but with a 2- to 3-fold reduction in analysis time, demonstrating the power of this approach for such applications. On the other hand, for the analysis of more polar extracts (e.g., Ginkgo biloba), the use of higher temperature was not beneficial, as it induced a significant decrease in retention, and thus resolving power, because of the increase in elution strength. The use of HT-UHPLC-TOF-MS raised the question of NP stability under high temperature conditions. This work demonstrated that no apparent degradation was evidenced at high temperature for a representative mixture of NPs and also for the different metabolites detected in the selected plant extracts.