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Jeffrey L Collett - One of the best experts on this subject based on the ideXlab platform.
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application of high performance anion exchange Chromatography pulsed amperometric detection for measuring carbohydrates in routine daily filter samples collected by a national network 1 determination of the impact of biomass burning in the upper midw
Journal of Geophysical Research, 2011Co-Authors: Amy P Sullivan, N H Frank, Gretchen D Onstad, Christopher D Simpson, Jeffrey L CollettAbstract:[1] Biomass burning is one of the major sources of organic carbon aerosols. However, there is limited information on the temporal and spatial variability for the impact of biomass burning in most regions of the United States, including the upper Midwest. In an attempt to obtain information on these variabilities, High-Performance Anion-Exchange Chromatography with pulsed amperometric detection (HPAEC-PAD) was employed to measure the smoke marker levoglucosan (and various other carbohydrates) on archived daily Federal Reference Monitor (FRM) Teflon filter samples from the PM2.5 NAAQS compliance monitoring network. Levoglucosan data, along with measurements of water-soluble organic carbon (WSOC) and potassium, from the analysis of FRM samples collected at 10 sites in the upper Midwest from March 2004 through February 2005 are presented. Results suggest that WSOC contains a substantial regional component, summer levoglucosan is dependent on both horizontal and vertical transport of fire emissions, and potassium revealed no clear pattern associated with biomass burning impacts. The contribution of organic carbon due to primary biomass burning particle emissions ranged on average from about 5 to 35%, suggesting that for this study in the upper Midwest, >50% of the WSOC is from secondary organic aerosol rather than biomass burning. In a second paper the results from the measurements of the other carbohydrates that HPAEC-PAD analysis can determine are discussed to investigate their sources and trends.
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application of high performance anion exchange Chromatography pulsed amperometric detection for measuring carbohydrates in routine daily filter samples collected by a national network 2 examination of sugar alcohols polyols sugars and anhydrosugars i
Journal of Geophysical Research, 2011Co-Authors: Amy P Sullivan, N H Frank, D M Kenski, Jeffrey L CollettAbstract:[1] Carbohydrate measurements of ambient samples can provide insights into the biogenic fraction of the organic carbon (OC) aerosol. However, lack of measurement on a routine basis limits data analysis. In a companion paper, 1 year of archived 1-in-6 day FRM (Federal Reference Monitor) filter samples from the PM2.5 NAAQS compliance monitoring network collected at 10 sites in the upper Midwest were analyzed using High-Performance Anion-Exchange Chromatography with pulsed amperometric detection to determine the regional impact of biomass burning. Along with levoglucosan, 13 other carbohydrates were simultaneously measured, including two more anhydrosugars (mannosan and galactosan), five sugars (arabinose, galactose, glucose, mannose, xylose), and six sugar alcohols/polyols (glycerol, methyltetrols, threitol/erythritol, xylitol, sorbitol, mannitol). This paper focuses on the results from these carbohydrates in order to investigate their sources and trends both spatially and temporally. Mannosan, galactosan, arabinose, xylose, and threitol/erythritol all correlated with levoglucosan (R2 from 0.43 to 0.97), suggesting biomass burning as their main source. Glucose and mannitol exhibited higher concentrations in summer and at more southern sites, likely due to vegetation differences at the sites. Using mannitol, the contribution of spores to OC was found to be <1%. Methyltetrols were highly correlated with water-soluble OC (R2 from 0.63 to 0.95) and in higher concentrations at more eastern sites. This spatial pattern is possibly due to these sites being downwind of the high isoprene emission zones that occur in the western part of the Midwest from oak forests in the Ozarks and spruce forests in the northern lake states.
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determination of levoglucosan in biomass combustion aerosol by high performance anion exchange Chromatography with pulsed amperometric detection
Atmospheric Environment, 2006Co-Authors: Guenter Engling, Jeffrey L Collett, Christian M Carrico, Sonia M Kreidenweis, William C Malm, Emily Lincoln, Yoshiteru Iinuma, Hartmut HerrmannAbstract:Abstract Atmospheric particulate matter can be strongly affected by smoke from biomass combustion, including wildfires, prescribed burns, and residential wood burning. Molecular source tracer techniques help determine contributions of biomass smoke to particle concentrations if representative source profiles are available. Various wood smoke source profiles have been generated for residential wood burning; however, few emission data are available for the combustion of biomass under open-burning conditions. Anhydrosugars, produced as thermal degradation products of cellulose and hemicellulose, are typically analyzed by gas Chromatography-mass spectrometry (GC-MS) after chemical derivatization. A simpler alternative analytical method, based on High-Performance Anion-Exchange Chromatography with pulsed amperometric detection (HPAEC-PAD), was developed here and utilized to measure several isomeric anhydrosugars (levoglucosan, mannosan, and galactosan) in primary smoke aerosol from various types of biomass and from different combustion conditions representative of prescribed and wildfires. Highly varying patterns were observed in the emission profiles of various molecular markers as a function of fuel type and combustion conditions. Emission factors of levoglucosan were a strong function of fuel type, combustion phase, and uphill versus downhill burn direction, varying from 36 to 1368 μg mg−1 organic carbon. Fuel type was the most important determinant, causing variations in emission factors of levoglucosan over an order of magnitude, while combustion phase and burn direction generally affected emission factors by a factor of 2–3. Mannosan and galactosan showed emission trends similar to levoglucosan. Levoglucosan emission factors from selected samples were compared to data obtained by two independent analytical methods, High-Performance liquid Chromatography (HPLC-MS) and GC-MS, showing rather good agreement. The HPAEC-PAD analytical method offers a simple alternative to GC-MS for future studies of aerosol concentrations of anhydrosugars, enabling more accurate estimates of contributions from biomass combustion to ambient particle concentrations.
Seonpyo Hong - One of the best experts on this subject based on the ideXlab platform.
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a pulsed amperometric detection method of galactose 1 phosphate for galactosemia diagnosis
Analytical Biochemistry, 2008Co-Authors: Jiseon Jeong, Hajeong Kwon, Yongmoon Lee, Hyeran Yoon, Taeyoun Choi, Seonpyo HongAbstract:Abstract Galactose 1-phosphate uridyltransferase deficiency causes the accumulation of galactose and galactose 1-phosphate (Gal 1-P) in the blood. We describe a new pulsed amperometric detection method for determining Gal 1-P levels as a pathognomic marker for the diagnosis of galactosemia. The method uses High-Performance Anion-Exchange Chromatography with pulsed amperometric detection. In an Anion-Exchange column, the analytes were separated in 5 min by the eluent mixture of 40 mM NaOH and 40 mM Na2CO3. The detection limit (signal to noise ratio of 3) to Gal 1-P was 30 μg/dL. The linear dynamic range was 3.0–50 mg/dL (r2 = 0.9999). The mean recoveries of Gal 1-P for intra- and interday assays were 97.55–103.78%. This method clearly separated the type I galactosemia patients from the normal group and is a practical procedure for the rapid diagnosis of galactosemia.
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determination of sugar phosphates by high performance anion exchange Chromatography coupled with pulsed amperometric detection
Journal of Chromatography A, 2007Co-Authors: Jiseon Jeong, Hajeong Kwon, Yongmoon Lee, Hyeran Yoon, Seonpyo HongAbstract:We have developed an improved analytical method for the determination of sugar phosphates using sodium carbonate (Na(2)CO(3)) for High-Performance Anion-Exchange Chromatography-pulsed amperometric detection. The target analytes were separated completely within 10 min using eluent containing 20 mM NaOH and 35 mM Na(2)CO(3). The limit of detection (S/N=3) and quantitation (S/N=10) for analytes were 10-30 ng/mL and 35-100 ng/mL, respectively. Linear dynamic range was 1-30 microg/mL (r(2)> or =0.9998). The RSDs for intra- and inter-day assays were found to be of satisfactory results (0.23-3.09%), and the recoveries from blood spots were 97.62-99.69%.
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development of a new diagnostic method for galactosemia by high performance anion exchange Chromatography with pulsed amperometric detection
Journal of Chromatography A, 2007Co-Authors: Jiseon Jeong, Hyeran Yoon, Seonpyo HongAbstract:Abstract We developed a new non-derivatization analytical method for the determination of galactose in the diagnosis of galactosemia by High-Performance Anion-Exchange Chromatography (HPAEC)-pulsed amperometric detection (PAD). With an Anion-Exchange column, the analytes were separated efficiently using 3 mM NaOH containing 1 mM NaOAc, and 200 mM NaOH was added for post-column reagent. The limit of detection (S/N = 3) and limit of quantification (S/N = 10) for galactose were 25 ng/mL and 83 ng/mL, respectively. Linear dynamic range was from 4.67 mg/dL to 53.46 mg/dL (r2 = 0.9999). The mean recovery of galactose for intra-, inter-day assays were found to be of satisfactory results (98.14–101.42%).
Manfred Wuhrer - One of the best experts on this subject based on the ideXlab platform.
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Analysis of urinary oligosaccharides in lysosomal storage disorders by capillary High-Performance Anion-Exchange Chromatography–mass spectrometry
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Cees Bruggink, Andre M Deelder, Ben J H M Poorthuis, Manfred WuhrerAbstract:Many lysosomal storage diseases are characterized by an increased urinary excretion of glycoconjugates and oligosaccharides that are characteristic for the underlying enzymatic defect. Here, we have used capillary High-Performance Anion-Exchange Chromatography (HPAEC) hyphenated to mass spectrometry to analyze free oligosaccharides from urine samples of patients suffering from the lysosomal storage disorders fucosidosis, α-mannosidosis, G_M1-gangliosidosis, G_M2-gangliosidosis, and sialidosis. Glycan fingerprints were registered, and the patterns of accumulated oligosaccharides were found to reflect the specific blockages of the catabolic pathway. Our analytical approach allowed structural analysis of the excreted oligosaccharides and revealed several previously unpublished oligosaccharides. In conclusion, using online coupling of HPAEC with mass spectrometric detection, our study provides characteristic urinary oligosaccharide fingerprints with diagnostic potential for lysosomal storage disorders.
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glycan profiling of urine amniotic fluid and ascitic fluid from galactosialidosis patients reveals novel oligosaccharides with reducing end hexose and aldohexonic acid residues
FEBS Journal, 2010Co-Authors: Cees Bruggink, Monique Piraud, Roseline Froissart, Andre M Deelder, Ben J H M Poorthuis, Manfred WuhrerAbstract:Urine, amniotic fluid and ascitic fluid samples of galactosialidosis patients were analyzed and structurally characterized for free oligosaccharides using capillary High-Performance Anion-Exchange Chromatography with pulsed amperometric detection and online mass spectrometry. In addition to the expected endo-β-N-acetylglucosaminidase-cleaved products of complex-type sialylated N-glycans, O-sulfated oligosaccharide moieties were detected. Moreover, novel carbohydrate moieties with reducing-end hexose residues were detected. On the basis of structural features such as a hexose–N-acetylhexosamine–hexose–hexose consensus sequence and di-sialic acid units, these oligosaccharides are thought to represent, at least in part, glycan moieties of glycosphingolipids. In addition, C1-oxidized, aldohexonic acid-containing versions of most of these oligosaccharides were observed. These observations suggest an alternative catabolism of glycosphingolipids in galactosialidosis patients: oligosaccharide moieties from glycosphingolipids would be released by a hitherto unknown ceramide glycanase activity. The results show the potential and versatility of the analytical approach for structural characterization of oligosaccharides in various body fluids.
Christina M Szabo - One of the best experts on this subject based on the ideXlab platform.
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complete monosaccharide analysis by high performance anion exchange Chromatography with pulsed amperometric detection
Analytical Chemistry, 2012Co-Authors: Zhenqing Zhang, Nazeer M Khan, Karen M Nunez, Edward K Chess, Christina M SzaboAbstract:Monosaccharide analysis is a critical way to profile the composition of complex carbohydrates. Methods to analyze neutral and amino sugars have been established for a long time, but methods for acidic sugars are rare. The acidic sugars, including uronic acids and sialic acids, are also important components in some complex carbohydrates. In this report, a High-Performance Anion-Exchange Chromatography method with pulsed amperometric detection was initially developed to analyze acidic sugars including different uronic acids and sialic acids. Subsequently, a method to profile complete monosaccharides, including most neutral, amino, and acidic sugars, was developed. This method has a limit of quantitation of ∼12.5 × 10–3 nmol for each sugar as well as good linearity over a wide range. This is a convenient procedure because it avoids additional derivatization of monosaccharides and has a broad application to a wide range of complex carbohydrates. The monosaccharide compositions of a variety of complex carbohyd...
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complete monosaccharide analysis by high performance anion exchange Chromatography with pulsed amperometric detection
Analytical Chemistry, 2012Co-Authors: Zhenqing Zhang, Nazeer M Khan, Karen M Nunez, Edward K Chess, Christina M SzaboAbstract:Monosaccharide analysis is a critical way to profile the composition of complex carbohydrates. Methods to analyze neutral and amino sugars have been established for a long time, but methods for aci...
Kyoko Koizumi - One of the best experts on this subject based on the ideXlab platform.
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isolation and characterization of cyclic α 1 4 glucans having degrees of polymerization 9 31 and their quantitative analysis by high performance anion exchange Chromatography with pulsed amperometric detection
Journal of Chromatography A, 1999Co-Authors: Kyoko Koizumi, Yoko Kubota, Haruyo Sanbe, Yoshinobu Terada, Takeshi TakahaAbstract:Abstract Cyclic α-(1→4)-glucans with degrees of polymerization (DPs) 9–31 were isolated from a mixture of cyclization products formed in the early stage of the action of cyclodextrin glucanotransferase (CGTase) on synthetic amylose, and characterized by matrix-assisted laser desorption ionization time-of-flight MS, 13C-NMR and HPLC of their partial acid hydrolyzates. High-Performance Anion-Exchange Chromatography (HPAEC) with pulsed amperometric detection for an accurate estimation of cyclic α-(1→4)-glucans was developed using those isolate glucans as quantification standards, and by HPAEC, the time course of the cyclization reaction of CGTase from an alkalophilic Bacillus sp. A2-5a on synthetic amylose was determined.
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estimation of the distributions of chain length of amylopectins by high performance liquid Chromatography with pulsed amperometric detection
Journal of Chromatography A, 1991Co-Authors: Kyoko Koizumi, Masako Fukuda, Susumu HizukuriAbstract:Abstract High-Performance Anion-Exchange Chromatography for a detailed estimation of the distribution of chain length of amylopectins was developed using a pulsed amperometric detector under alkaline conditions. As maltosaccharides having different degrees of polymerization, which were produced by debranching of amylopectin with isoamylase, exhibit different pulsed amperometric detector responses, the individual maltosaccharides (degree of polymerization 6–17) were isolated by High-Performance liquid Chromatography on an amino column and an octadecylsilane column to use as quantification standards. By the use of this High-Performance Anion-Exchange Chromatography the chain length distributions of some typical amylopectins were characterized in detail.
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high performance anion exchange Chromatography of homogeneous d gluco oligosaccharides and polysaccharides polymerization degree 50 with pulsed amperometric detection
Journal of Chromatography A, 1991Co-Authors: Kyoko Koizumi, Yoko Kubota, Toshiko Tanimoto, Yasuyo OkadaAbstract:Abstract High-Performance Anion-Exchange Chromatography under alkaline conditions with pulsed amperometric detection was applied to the analyses of (1 → 2)-, (1 → 3)-, (1 → 4)- and (1 → 6)-linked homogeneous α- or β- d -gluco-oligosaccharides and -polysaccharides up to a degree of polymerization (DP) of ⩾ 50. Each series of homogeneous d -gluco-oligomers and -polymers showed a linear relationship between log k′ and DP in isocratic elution using 150 mM sodium hydroxide solution containing 100 mM sodium acetate as the eluent. An effective separation of individual members of an homologous series of linear glucans was achieved using gradient elution, accomplished by maintaining the sodium hydroxide concentration at 150 mM and increasing the sodium acetate concentration during the analysis. The detector response per HCOH group in d -gluco-oligomers (DP 2–7) was almost the same.