The Experts below are selected from a list of 741 Experts worldwide ranked by ideXlab platform
John G Gambertoglio - One of the best experts on this subject based on the ideXlab platform.
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paired ion reversed phase hplc assay for the determination of iothalamic Acid and para Aminohippuric Acid in urine
Journal of Pharmaceutical and Biomedical Analysis, 1994Co-Authors: Ananda K Seneviratne, Anura L Jayewardene, John G GambertoglioAbstract:Abstract A paired ion reversed-phase high performance liquid chromatographic method for simultaneous determination of iothalamic Acid (Io) and para Aminohippuric Acid (PAH) in urine is described. The method uses a single internal standard for both drugs. The only sample preparation required is dilution of urine (1:100 or 1:500) with deionized water. The internal standard is added to a small aliquot of the diluted specimen and injected. For HPLC, a C 8 column and a mobile phase consisting of potassium phosphate buffer with dodecyl triethylammonium phosphate IP reagent, 25% organic modifier with UV detection at 254 nm was used. Within day and between day variation for the assay were in the range of 1.48–9.46% for iothalamic Acid and 1.84–10.36% for para Aminohippuric Acid for four levels of concentration. Limits of quantitation were 50.0 μg ml −1 for iothalamic Acid and 75.0 μg ml −1 for para Aminohippuric Acid. Mean recovery was 98.55% for Io and 97.79% for PAH. This isocratic HPLC assay is simple, rapid and relatively inexpensive.
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paired ion reversed phase hplc assay for the simultaneous determination of iothalamic Acid and para Aminohippuric Acid in plasma
Journal of Liquid Chromatography & Related Technologies, 1994Co-Authors: Anura L Jayewardene, Ananda K Seneviratne, John G GambertoglioAbstract:Abstract An ion paired reversed—phase high performance liquid chromatographic assay for iothalamic Acid and para Aminohippuric Acid in the same sample of plasma is described. The analysis uses one internal standard for both drugs. Sample preparation consists of precipitating plasma proteins with methanol and centrifuging to settle the proteins. The supernatant is evaporated and the residue reconstituted with mobile phase for injection. For HPLC a C8 column and a mobile phase consisting of potassium phosphate buffer with dodecyl triethyl ammonium phosphate IP reagent, 22.5% methanol and 2.5% acetonitrile with UV detection at 254 nm was used. Coefficients of variation for the assay were in the range of 1.6–12.1% for iothalamic Acid and 4.3–17.7% for para Aminohippuric Acid for four levels of concentration. Limits of quantitation were 3.0 μg/mL for iothalamic Acid and 5.0 μg/mL for para Aminohippuric Acid. This isocratic HPLC assay is simple, rapid and relatively inexpensive.
Liheng Pao - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a liquid chromatography tandem mass spectrometry method for simultaneous quantification of p Aminohippuric Acid and inulin in rat plasma for renal function study
Analytical and Bioanalytical Chemistry, 2010Co-Authors: Changching Lin, Chienwen Kuo, Liheng PaoAbstract:The first liquid chromatography–tandem mass spectrometry method was developed and validated for the simultaneous quantification of p-Aminohippuric Acid and inulin, both typical biomarkers of kidney function. 5-(Hydroxymethyl)furfural, generated from inulin by Acid and heat preparation, was used as an inulin substitute for the quantification. Acetaminophen was used as the internal standard. Solid-phase extraction was carried out with 5% methanol as the washing solution to optimize the retention of the analytes and to avoid obstruction of the orifice plate of the mass spectrometer caused by any unreacted inulin residue remaining from the sample preparation process. Chromatography separation was performed on a Symmetry C18 column and a mobile phase composed of 2 mM ammonium formate and 0.1% formic Acid in water (solvent A) and 2 mM ammonium formate and 0.1% formic Acid in acetonitrile (solvent B) (30:70, v/v). Detection was performed with a triple-quadrupole tandem mass spectrometer using positive ion mode electrospray ionization in the multiple reaction monitoring mode. The selected transitions were m/z 195.2 → 120.2, 127.1 → 109.1, and 152.1 → 110.0 for p-Aminohippuric Acid, inulin [measured as 5-(hydroxymethyl)furfural], and acetaminophen, respectively. The linearity ranged from 10 to 140 μg/mL and from 100 to 1,400 μg/mL for p-aminohippurric Acid and inulin (r > 0.99), respectively. The precisions and accuracies were all within 12 and 11% for the lower limit of quantification and quality control samples, respectively. This application was proven to be reliable and accurate and was successfully applied to a renal function study.
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determination of p Aminohippuric Acid in rat plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2010Co-Authors: Hsienyuan Fan, Changching Lin, Liheng PaoAbstract:A rapid, simple and sensitive method was developed for the determination of para-Aminohippuric Acid (PAH) in rat plasma using liquid chromatography tandem mass spectrometry (LC-MS-MS). Acetaminophen was used as the internal standard. Chromatographic separation was performed using a Symmetry C18 column and the mobile phase was composed of A: 2 mM ammonium formate and 0.1% formic Acid in water and B: 2 mM ammonium formate and 0.1% formic Acid in acetonitrile (ACN) (A:B, 30:70, v/v). Detection was performed on a triple-quadrupole tandem mass spectrometer using positive ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The MS/MS ion transitions monitored were m/z 195.2-->120.2 and 152.1-->110.1 for PAH and acetaminophen, respectively. Good linearity is observed over the concentration range of 0.1-500 microg/ml. The method was proved to be accurate and reliable and was applied to a pharmacokinetic study in rat.
Shan-jing Yao - One of the best experts on this subject based on the ideXlab platform.
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coadsorption of human immunoglobulin g and bovine serum albumin on a p Aminohippuric Acid based mixed mode resin
Journal of Chemical & Engineering Data, 2016Co-Authors: Jun Yan, Qi-lei Zhang, Dong-qiang Lin, Shan-jing YaoAbstract:Mixed-mode chromatography (MMC) has been developed as a cost-effective new technique for antibody purification. Nuvia cPrime (NP) is a novel MMC resin with p-Aminohippuric Acid as the functional ligand. The adsorption of human immunoglobulin G (IgG) and bovine serum albumin (BSA) on NP was measured, including single component adsorption at different pH and binary coadsorption at various pH values and IgG/BSA mass ratios. Typical pH-dependent adsorption behavior was found in the single component adsorption which can be described by a two-parameter equation that offered a convenient way to analyze pH effects. Moreover, a competitive and preferential adsorption of IgG to BSA was investigated in binary coadsorption. Extended Langmuir (EL) and Extended Langmuir−Freundlich (ELF) models with parameters obtained from single-component isotherms were used to describe the coadsorption behaviors of IgG and BSA at various mass ratios. The results indicated the ELF model was more suitable for IgG adsorption, while the ...
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Coadsorption of Human Immunoglobulin G and Bovine Serum Albumin on a p‑Aminohippuric Acid Based Mixed-Mode Resin
2016Co-Authors: Jun Yan, Qi-lei Zhang, Dong-qiang Lin, Shan-jing YaoAbstract:Mixed-mode chromatography (MMC) has been developed as a cost-effective new technique for antibody purification. Nuvia cPrime (NP) is a novel MMC resin with p-Aminohippuric Acid as the functional ligand. The adsorption of human immunoglobulin G (IgG) and bovine serum albumin (BSA) on NP was measured, including single component adsorption at different pH and binary coadsorption at various pH values and IgG/BSA mass ratios. Typical pH-dependent adsorption behavior was found in the single component adsorption which can be described by a two-parameter equation that offered a convenient way to analyze pH effects. Moreover, a competitive and preferential adsorption of IgG to BSA was investigated in binary coadsorption. Extended Langmuir (EL) and Extended Langmuir−Freundlich (ELF) models with parameters obtained from single-component isotherms were used to describe the coadsorption behaviors of IgG and BSA at various mass ratios. The results indicated the ELF model was more suitable for IgG adsorption, while the EL model was better for describing the weak binding of BSA at pH 7.0 and 8.0
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Protein adsorption behavior and immunoglobulin separation with a mixed-mode resin based on p-Aminohippuric Acid.
Journal of Separation Science, 2014Co-Authors: Jun Yan, Qi-lei Zhang, Dong-qiang Lin, Shan-jing YaoAbstract:p-Aminohippuric Acid is a newly developed ligand for mixed-mode chromatography with a commercial resin name of Nuvia cPrime. In this study, bovine immunoglobulin G and bovine serum albumin were used as two model proteins, and the adsorption isotherms with Nuvia cPrime were investigated under different pH and salt concentrations. The results showed that pH had a strong but different influence on the adsorption of these two proteins. The adsorption capacity for bovine immunoglobulin G and BSA was 170.4 and 28.1 mg/g at pH 6.0, respectively. Different salts also showed varying effects on the protein adsorption. Moreover, the adsorption and elution behaviors of the two proteins in a column were determined under varying pH and salt concentrations. An optimized process showed that feedstock loaded under pH 6.0 with 0.8 M (NH4)2SO4 and eluted under pH 8.0 with 1.0 M NaCl could effectively purify bovine immunoglobulin G from feedstock containing BSA. The purity of bovine immunoglobulin G could reach 99.8% and the recovery was 92.7%. The results demonstrated that the control of pH and salt addition during the loading and elution processes were two key factors in improving separation efficiency with Nuvia cPrime resin.
Ananda K Seneviratne - One of the best experts on this subject based on the ideXlab platform.
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paired ion reversed phase hplc assay for the determination of iothalamic Acid and para Aminohippuric Acid in urine
Journal of Pharmaceutical and Biomedical Analysis, 1994Co-Authors: Ananda K Seneviratne, Anura L Jayewardene, John G GambertoglioAbstract:Abstract A paired ion reversed-phase high performance liquid chromatographic method for simultaneous determination of iothalamic Acid (Io) and para Aminohippuric Acid (PAH) in urine is described. The method uses a single internal standard for both drugs. The only sample preparation required is dilution of urine (1:100 or 1:500) with deionized water. The internal standard is added to a small aliquot of the diluted specimen and injected. For HPLC, a C 8 column and a mobile phase consisting of potassium phosphate buffer with dodecyl triethylammonium phosphate IP reagent, 25% organic modifier with UV detection at 254 nm was used. Within day and between day variation for the assay were in the range of 1.48–9.46% for iothalamic Acid and 1.84–10.36% for para Aminohippuric Acid for four levels of concentration. Limits of quantitation were 50.0 μg ml −1 for iothalamic Acid and 75.0 μg ml −1 for para Aminohippuric Acid. Mean recovery was 98.55% for Io and 97.79% for PAH. This isocratic HPLC assay is simple, rapid and relatively inexpensive.
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paired ion reversed phase hplc assay for the simultaneous determination of iothalamic Acid and para Aminohippuric Acid in plasma
Journal of Liquid Chromatography & Related Technologies, 1994Co-Authors: Anura L Jayewardene, Ananda K Seneviratne, John G GambertoglioAbstract:Abstract An ion paired reversed—phase high performance liquid chromatographic assay for iothalamic Acid and para Aminohippuric Acid in the same sample of plasma is described. The analysis uses one internal standard for both drugs. Sample preparation consists of precipitating plasma proteins with methanol and centrifuging to settle the proteins. The supernatant is evaporated and the residue reconstituted with mobile phase for injection. For HPLC a C8 column and a mobile phase consisting of potassium phosphate buffer with dodecyl triethyl ammonium phosphate IP reagent, 22.5% methanol and 2.5% acetonitrile with UV detection at 254 nm was used. Coefficients of variation for the assay were in the range of 1.6–12.1% for iothalamic Acid and 4.3–17.7% for para Aminohippuric Acid for four levels of concentration. Limits of quantitation were 3.0 μg/mL for iothalamic Acid and 5.0 μg/mL for para Aminohippuric Acid. This isocratic HPLC assay is simple, rapid and relatively inexpensive.
Changching Lin - One of the best experts on this subject based on the ideXlab platform.
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development and validation of a liquid chromatography tandem mass spectrometry method for simultaneous quantification of p Aminohippuric Acid and inulin in rat plasma for renal function study
Analytical and Bioanalytical Chemistry, 2010Co-Authors: Changching Lin, Chienwen Kuo, Liheng PaoAbstract:The first liquid chromatography–tandem mass spectrometry method was developed and validated for the simultaneous quantification of p-Aminohippuric Acid and inulin, both typical biomarkers of kidney function. 5-(Hydroxymethyl)furfural, generated from inulin by Acid and heat preparation, was used as an inulin substitute for the quantification. Acetaminophen was used as the internal standard. Solid-phase extraction was carried out with 5% methanol as the washing solution to optimize the retention of the analytes and to avoid obstruction of the orifice plate of the mass spectrometer caused by any unreacted inulin residue remaining from the sample preparation process. Chromatography separation was performed on a Symmetry C18 column and a mobile phase composed of 2 mM ammonium formate and 0.1% formic Acid in water (solvent A) and 2 mM ammonium formate and 0.1% formic Acid in acetonitrile (solvent B) (30:70, v/v). Detection was performed with a triple-quadrupole tandem mass spectrometer using positive ion mode electrospray ionization in the multiple reaction monitoring mode. The selected transitions were m/z 195.2 → 120.2, 127.1 → 109.1, and 152.1 → 110.0 for p-Aminohippuric Acid, inulin [measured as 5-(hydroxymethyl)furfural], and acetaminophen, respectively. The linearity ranged from 10 to 140 μg/mL and from 100 to 1,400 μg/mL for p-aminohippurric Acid and inulin (r > 0.99), respectively. The precisions and accuracies were all within 12 and 11% for the lower limit of quantification and quality control samples, respectively. This application was proven to be reliable and accurate and was successfully applied to a renal function study.
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determination of p Aminohippuric Acid in rat plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography B, 2010Co-Authors: Hsienyuan Fan, Changching Lin, Liheng PaoAbstract:A rapid, simple and sensitive method was developed for the determination of para-Aminohippuric Acid (PAH) in rat plasma using liquid chromatography tandem mass spectrometry (LC-MS-MS). Acetaminophen was used as the internal standard. Chromatographic separation was performed using a Symmetry C18 column and the mobile phase was composed of A: 2 mM ammonium formate and 0.1% formic Acid in water and B: 2 mM ammonium formate and 0.1% formic Acid in acetonitrile (ACN) (A:B, 30:70, v/v). Detection was performed on a triple-quadrupole tandem mass spectrometer using positive ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The MS/MS ion transitions monitored were m/z 195.2-->120.2 and 152.1-->110.1 for PAH and acetaminophen, respectively. Good linearity is observed over the concentration range of 0.1-500 microg/ml. The method was proved to be accurate and reliable and was applied to a pharmacokinetic study in rat.