Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Impact Factor & Information

Publisher: Elsevier

Journal description

The Journal of Chromatography B. addresses advancements in and applications of analytical methodologies related to drugs, other pharmacologically active compounds, metabolites, as well as to bio-polymers such as proteins and nucleic acids. The areas considered include: clinical analysis, therapeutic drug monitoring, pharmaceutical analysis and novel approaches to sample preparation in bioanalysis; the qualitative and quantitative analysis of proteins, peptides and their post-translational modifications as well as nucleic acids; the screening and profiling of body fluids and tissues related to monitoring the level of active substances, including metabolites, biomarkers and toxicants; the comparative analysis of biological systems and proteomics and genomics including novel ways of data handling and interpretation; analytical techniques covered include the various facets of chromatography, electrophoresis and related methods, including mass spectrometry and affinity-based methodologies.

Current impact factor: 2.69

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 2.694
2012 Impact Factor 2.487
2011 Impact Factor 2.888
2010 Impact Factor 2.971
2009 Impact Factor 2.777
2008 Impact Factor 2.5
2007 Impact Factor 2.935
2006 Impact Factor 2.647
2005 Impact Factor 2.391
2004 Impact Factor 2.176
2003 Impact Factor 2.085
2002 Impact Factor 1.913
1996 Impact Factor 1.341
1995 Impact Factor 1.255
1994 Impact Factor 1.209

Impact factor over time

Impact factor
Year

Additional details

5-year impact 0.00
Cited half-life 6.60
Immediacy index 0.36
Eigenfactor 0.04
Article influence 0.73
Website Journal of Chromatography B website
ISSN 1873-376X

Publisher details

Elsevier

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    • Author's post-print must be released with a Creative Commons Attribution Non-Commercial No Derivatives License
    • Publisher last reviewed on 03/06/2015
  • Classification
    ​ green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: A rapid and simple turbulent flow liquid chromatography (TFC-LC) method implementing positive heated electrospray ionization (HESI) for the accurate and precise determination of methotrexate (MTX), 7-hydroxy methotrexate (7-OH MTX), and 4-amino-4-deoxy-N(10)-methylpteroic acid (DAMPA) concentrations in serum was developed. MTX was isolated from serum samples (100μL) after protein precipitation with methanol containing formic acid and internal standard (MTX-D3) followed by centrifugation. The supernatant was injected into the turbulent flow liquid chromatography which is followed by electrospray positive ionization tandem mass spectrometry (TFC-LC-MS/MS) and quantified using a six-point calibration curve. For MTX and DAMPA the assays were linear from 10 to 1000nmol/L and for 7-OH MTX from 20 to 2000nmol/L. Dilutions of 10, 100 and 1000-fold were validated giving a clinically reportable range of 10nmol/L to 5×10(5)nmol/L. Within-day and between-day precisions at concentrations spanning the analytical measurement ranges were less than 10% for all three analytes. MTX, DAMPA and 7-OH MTX were sufficiently stable under all relevant analytical conditions. No significant matrix effect was observed during the method validation. The TFC-LC-MS/MS MTX method was also compared with three other clinically validated MTX assays: a dihydrofolate reductase (DHFR) inhibition assay, an immunoassay based on fluorescence polarization and a previously developed LC-MS/MS assay. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:169-175. DOI:10.1016/j.jchromb.2015.08.025
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    ABSTRACT: Despite the biological importance of membrane proteins, their analysis has lagged behind that of soluble proteins and still presents a great challenge mainly because of their highly hydrophobic nature and low abundance. Sodium deoxycholate (SDC)-assisted digestion strategy has been introduced in our previous papers, which cleverly circumvents many of the challenges in shotgun membrane proteomics. However, it is associated with significant sample loss due to the slightly weaker extraction/solubilization ability of 1% SDC. In this study, an enhanced SDC-assisted digestion method (ESDC method) was developed that incorporates the almost strongest ability of SDC with a high concentration (5%) to lyse membrane and extract/solubilize hydrophobic membrane proteins, and then dilution to 1% for more efficient digestion. The comparative study using rat liver membrane-enriched sample showed that, compared with previous SDC-assisted method and the "universal" filter-aided sample preparation (FASP) method, the ESDC method not only increased the identified number of total proteins, membrane proteins, hydrophobic proteins, integral membrane proteins (IMPs) and IMPs with more than 5 transmembrane domains (TMDs) by an average of 10.8%, 13.2%, 17.8%, 17.9% and 52.9%, respectively, but also enhanced the identified number of total peptides and hydrophobic peptides by averagely 12.5% and 14.2%. These results demonstrated that the ESDC method provides a substantial improvement in the recovery and identification of membrane proteins, especially those with high hydrophobicity and multiple TMDs, and thereby displaying more potential for shotgun membrane proteomics. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:144-151. DOI:10.1016/j.jchromb.2015.08.019
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    ABSTRACT: An enantioselective high performance liquid chromatography method has been developed and validated by evaluating the suitability of newly introduced immobilized polysaccharide chiral stationary phases, the effect of different organic modifiers and temperature including the entropy and enthalpy on resolution of the (R,S)-(-) & (S,R)-(+) emtricitabine enantiomers on rat dried blood spots. Both the enantiomers were extracted from dried blood spots using ethanol: methanol (80:20 v/v) mixture and separated on an immobilized amylose tris-(3,5-dimethyl phenyl carbamate) chiral stationary phase using n-hexane:ethanol (65:35 v/v) as a mobile phase at a flow rate of 0.8mL/min. The detection was carried out at 280nm using photo diode array detector connected to a polarimeter in series to determine their order of eluton. The method was validated with respect to limits of detection and quantification, linearity, accuracy and precision. The calibration curves were linear over the concentration range of 0.5-500μg/mL for both enantiomers and the correlation coefficient (r(2)) was >0.998. The overall recovery of (R,S)- & (S,R)-enantiomers of emtricitabin from DBS were 90.4 and 90.6%, respectively. The limits of detection and quantification of enantiomers were 0.26, 0.30 and 0.85, 0.92μg/mL for (R,S)- and (S,R)-emtricitabin enantiomers, respectively. The assay was specific and precise (RSD <10%). The stability of emtricitabin was also performed and the results were found to be well within the limits. The effect of hematocrit on extraction of emtricitabin enantiomers from dried blood spots was evaluated and no interference from endogenous substances was observed. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:160-168. DOI:10.1016/j.jchromb.2015.08.016
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    ABSTRACT: Vanillylmandelic acid (VMA), as one of the most important catecholamine metabolites, is commonly used to aid in diagnosis of pheochromocytoma. This study develops a rapid and simple high-throughput LC-MS/MS method for the measurement of urinary VMA. Without sample pretreatment, the urine specimens were mixed with internal standard (IS) solution for direct analysis by LC-MS/MS in two minutes. VMA and VMA-d3 were detected in the multiple-reaction monitoring mode using the specific transitions m/z 197.0→137.0 and 200.0→140.0, respectively. This method was validated for consistent linearity from 1.0 to 250.0μM with CVs≤3.12%, excellent recovery, good stability and low carryover. The lowest limit of quantification (LLOQ) was 0.125μmol/L for VMA with CV of 14.1%, and the lower limit of detection (LOD) was 0.025μmol/L. Intra-assay and inter-assay imprecision values (CVs) for VMA were all below 2.11%. Dilution linearity was investigated with a satisfied mean accordance of 105%. Method comparison of LC-MS/MS and microcolumn chromatography in our lab was performed and the reference interval was established in agreement with that of the Mayo Clinic. All these results demonstrate that this validated LC-MS/MS approach shows improved accuracy and reproducibility compared with microcolumn chromatography. The low sample volume, simplicity, rapidity, and robustness of the method make it suitable for use as a high-throughput assay in routine clinical biochemistry laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:92-97. DOI:10.1016/j.jchromb.2015.08.013
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    ABSTRACT: Melittin is the major toxin peptide in bee venom, which has diverse biological effects. In the present study, melittin was separated by reverse-phase high-performance liquid chromatography, and was then detected using intrinsic fluorescence signal of tryptophan residue. The accuracy, linearity, limit of quantitation (LOQ), intra-day and inter-day precision of the method were carefully validated in this study. Results indicate that the intrinsic fluorescence signal of melittin has linear range from 0.04μg/mL to 20μg/mL with LOQ of 0.04μg/mL. The recovery range of spiked samples is between 81.93% and 105.25%. The precision results are expressed as relative standard deviation (RSD), which is in the range of 2.1-7.4% for intra-day precision and 6.2-10.8% for inter-day precision. Because of the large linear dynamic range and the high sensitivity, intrinsic fluorescence detection (IFD) can be used for analyzing melittin contents in individual venom sac of honeybee (Apis mellifera). The detected contents of melittin in individual bee venom sac are 0.18±0.25μg for one-day old honeybees (n=30), and 114.98±43.51μg for 25-day old (n=30) honeybees, respectively. Results indicate that there is large bee-to-bee difference in melittin contents. The developed method can be useful for discovering the melittin related honeybee biology information, which might be covered in the complex samples. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:139-143. DOI:10.1016/j.jchromb.2015.08.014
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    ABSTRACT: A simple, rapid and sensitive reversed-phase high performance liquid chromatography (HPLC) method has been developed for the determination of methotrexate in human serum. After deproteinization of the serum with 40% silver nitrate solution, methotrexate and internal standard (IS) were separated on a reversed-phase column with a mobile phase consisting of 10mM sodium phosphate buffer (pH6.40)-methanol (78:22%, v/v) and ultraviolet detection at 310nm. The linearity is evaluated by a calibration curve in the concentration range of 0.05-10.0μg/mL and presented a correlation coefficient of 0.9995. The absolute recoveries were 97.52±3.9% and 96.87±3.7% for methotrexate and ferulic acid (internal standard), respectively. The intra- and inter-day precision were less 6.19 and 5.89%, respectively (n=6). The limit of quantitation was 0.02μg/mL and the limit of detection was 0.006μg/mL. The complete analysis was achieved less than 10min with no interference from endogenous components or 22 examined drugs. This method was validated by using serum samples from high-dose methotrexate treated patients with osteosarcoma, breast cancer, acute leukemia and lymphoma. The method was demonstrated to be a simple, rapid and reliable approach in quantification of methotrexate in serum samples from patients with high-dose methotrexate therapy. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:107-112. DOI:10.1016/j.jchromb.2015.08.017
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    ABSTRACT: 1,3-Butadiene (BD) is a ubiquitous environmental pollutant found in tobacco smoke. In vivo, BD is mainly metabolized to form monohydroxybutenylmercapturic acid (MHBMA) and N-acetyl-S-(3, 4-dihydroxybutyl) cysteine (DHBMA). The accurate quantification of MHBMA and DHBMA in urine may provide important insights into the actual internal exposure of the general population to BD. 8-Hydroxy-2-deoxyguanosine (8-OHdG) is the biomarker of oxidative damage. In this study, a column-switching LC-MS/MS method was developed and validated for the simultaneous quantification of MHBMA, DHBMA derived from BD exposure and 8-OHdG in human urine. Urine samples were loaded on a LiChrospher(®) RP-8 ADS (25μm) 25×4mm RAM column for the extraction and clean-up of analytes. The separation was achieved using a SUPELCO(®) LC-18-DB column (75mm×3.0mm, 3μm). The analytes were ionized in negative electrospray ionization mode and analyzed in multiple reaction monitoring mode. Under optimum conditions, recoveries ranged from 78.9% to 101.7%, with relative standard deviations less than 11%. The limits of quantification ranged from 0.15 to 0.27ng/mL, highlighting the high sensitivity of this simple method. The validated method was successfully applied to analysis urine samples from 56 non-smokers and 233 smokers who smoked cigarettes with 3 different tar yields. There was a correlation between urinary MHBMA, DHBMA and 8-OHdG. This method did not require any preparation process and efficiently removed interference from the matrix by using column-switching. The developed method is applicable to epidemiological studies. Copyright © 2015. Published by Elsevier B.V.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:123-129. DOI:10.1016/j.jchromb.2015.08.012
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    ABSTRACT: Epigallocatechin-3-gallate (EGCG) is a major bioactive ingredient of green tea that produces beneficial neuroprotective effects. In this paper, to optimize the EGCG enrichment, thirteen macroporous resins with different chemical and physical properties were systemically evaluated. Among the thirteen tested resins, the H-bond resin HPD826 exhibited best adsorption/desorption capabilities and desorption ratio, as well as weakest affinity for caffeine. The absorption of EGCG on the HPD826 resin followed the pseudo-second-order kinetics and Langmuir isotherm model. The separation parameters of EGCG were optimized by dynamic adsorption/desorption experiments with the HPD826 resin column. Under the optimal condition, the content of EGCG in the 30% ethanol eluent increased by 5.8-fold from 7.7% to 44.6%, with the recovery yield of 72.1%. After further purification on a polyamide column, EGCG with 74.8% purity was obtained in the 40-50% ethanol fraction with a recovery rate of 88.4%. In addition, EGCG with 95.1% purity could be easily obtained after one-step crystallization in distilled water. Our study suggests that the combined macroporous resin and polyamide column chromatography is a simple method for large-scale separation and purification of EGCG from natural plants for food and pharmaceutical applications. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:113-122. DOI:10.1016/j.jchromb.2015.07.055
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    ABSTRACT: A liquid chromatography-tandem mass spectrometric (LC-MS/MS) method using positive/negative electrospray ionization (ESI) switching for the simultaneous quantitation of carboprost methylate and carboprost in dog plasma has been developed and validated. After screening, the esterase inhibitor, dichlorvos was added to the whole blood at a ratio of 1:99 (v/v) to stabilize carboprost methylate during blood collection, sample storage and LLE. Indomethacin was added to plasma to inhibit prostaglandins synthesis after sampling. After liquid-liquid extraction of 500μL plasma with ethyl ether-dichloromethane (75:25, v/v), analytes and internal standard (IS), alprostadil-d4, were chromatographed on a CAPCELL PAK Phenyl column (150×2.0mm, 5μm) using acetonitrile-5mM ammonium acetate as mobile phase. Carboprost methylate was detected by positive ion electrospray ionization followed by multiple reaction monitoring (MRM) of the transition at m/z 400.5→329.3; the carboprost and IS were detected by negative ion electrospray ionization followed by MRM of the transitions at m/z 367.2→323.2, and 357.1→321.2, respectively. The method was linear for both analytes in the concentration range 0.05-30ng/mL with intra- and inter-day precisions (as relative standard deviation) of ≤6.75% and accuracy (as relative error) of ≤7.21% and limit of detection (LOD) values were 10 and 20pg/mL, respectively. The method was successfully applied to a pharmacokinetic study of the analytes in beagle dogs after intravaginal administration of a suppository containing 0.5mg carboprost methylate. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 998. DOI:10.1016/j.jchromb.2015.05.039
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    ABSTRACT: In this study, a simple, sensitive, and robust analytical method based on ultra-performance liquid chromatography (UPLC) has been developed for the determination of galangin in rat plasma using diazepam as internal standard (IS). After sample preparation by a simple liquid-liquid extraction, chromatography was performed on an Acquity UPLC BEH C18 column (2.1mm×50mm, 1.7μm particle size) and ultraviolet detection set at a wavelength of 360nm. The method was linear over the concentration range 10-1000ng/mL with a lower limit of quantification (LLOQ) of 10ng/mL. Inter- and intra-day precision (RSD %) were all within 9.5% and the accuracy (RE %) was equal or lower than 8.9%. Recoveries of galangin and IS were more than 78.3%. Stability studies showed that galangin was stable under a variety of storage conditions. The method was successfully applied to a pharmacokinetic study involving oral administration of galangin to rats. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 998. DOI:10.1016/j.jchromb.2015.06.024
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    ABSTRACT: E6005, a novel phosphodiesterase 4 inhibitor, is currently under clinical development for the treatment of atopic dermatitis. As ER-392710 (M11), a hydrolyzed metabolite, is a main metabolite, a simultaneous assay method for quantification of E6005 and M11 in human plasma has been developed and validated using ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS). E6005, M11, and each deuterium-labeled compound used as internal standard were extracted from 100μL human plasma by solid phase extraction then chromatographed on an Acquity UPLC BEH C18 column (100mm×2.1mm i.d., 1.7μm) under gradient elution. The analytes were detected by selected reaction monitoring in the positive ion mode with the mass transition of m/z 473.1/163.0 and m/z 459.1/149.0 for E6005 and M11, respectively. E6005 and M11 were quantifiable ranging from 1 to 200ng/mL with no carryover. Accuracy and precision in intra- and inter-batch reproducibility assays were within the acceptance criteria recommended by the regulatory bioanalytical guidelines. Various stability assessments including possible conversion of E6005 to M11 were thoroughly performed to demonstrate the stability of E6005 and M11 in human blood and plasma. The method was successfully applied to support clinical trials. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 998. DOI:10.1016/j.jchromb.2015.06.023
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    ABSTRACT: A novel chemometrics-assisted high performance liquid chromatography method coupled with diode array detector (HPLC-DAD) was proposed for the simultaneous determination of vincristine (VCR), vinblastine (VLB), vindoline (VDL), catharanthine (CAT) and yohimbine (YHB) in Catharanthus roseus (C. roseus) and human serum samples. With the second-order advantage of the alternating trilinear decomposition (ATLD) method, the resolution and rapid determination of five components of interest in complex matrices were performed, even in the present of heavy overlaps and unknown interferences. Therefore, multi-step purification was omitted and five components could be fast eluted out within 7.5min under simple isocratic elution condition (acetonitrile/0.2% formic acid water, 37:63, v/v). Statistical parameters, such as the linear correlation coefficient (R(2)), root-mean-square error of prediction (RMSEP), limit of detection (LOD) and limit of quantitation (LOQ) had been calculated to investigate the accuracy and reliability of the method. The average recoveries of five vinca alkaloids ranged from 97.1% to 101.9% and 98.8% to 103.0% in C. roseus and human serum samples, respectively. The five vinca alkaloids were adequately determined with limits of detection (LODs) of 29.5-49.3ngmL(-1) in C. roseus and 12.4-27.2ngmL(-1) in human serum samples, respectively. The obtained results demonstrated that the analytical strategy provided a feasible alternative for synchronously monitoring the quality of raw herb and the concentration of blood drugs. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; DOI:10.1016/j.jchromb.2015.08.008
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    ABSTRACT: A simple method based on matrix solid phase dispersion (MSPD) using molecularly imprinted polymers (MIPs) as sorbents for selective extraction of malachite green (MG) from aquatic products was developed. The MIPs were prepared by using carbon nanotube as support, MG as template, methacrylic acid as functional monomer, ethyleneglycol dimethacrylate as crosslinker and methylene chloride as solvent. The MIPs were characterized by Fourier transform infrared spectrometry and transmission electron microscopy. The isothermal adsorption, kinetics absorption and selective adsorption experiments were carried out. We optimized the extraction conditions as follows: the ratio of MIPs to sample was 2:3, the dispersion time was 15min, washing solvent was 4mL 50% aqueous methanol and elution solvent was 3mL methanol-acetic acid (98: 2, v/v). Once the MSPD process was completed, the MG extracted from aquatic products was determined by high performance liquid chromatography. The detection limit of MG was 0.7μgkg(-1). The relative standard deviations of intra-day and inter-day were obtained in the range of 0.9%-4.7% and 3.4%-9.8%, respectively. In order to evaluate the applicability and reliability of the proposed method, it was applied to determine MG in different aquatic products samples including fish, shrimp, squid and crabs. The satisfied recoveries were in the range of 89.2%-104.6%. The results showed that this method is faster, simpler and makes extraction and purification in the same system. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:98-106. DOI:10.1016/j.jchromb.2015.08.002
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    ABSTRACT: Antibody drug conjugates (ADCs) are complex molecules composed of two pharmacologically distinct components, the cytotoxic payload and the antibody. The measurement of the payload molecules that are attached to the antibody in vivo is important for the evaluation of the safety and efficacy of ADCs, and can also provide distinct information compared to the antibody-related analytes. However, analyzing the antibody-conjugated payload is challenging and in some cases may not be feasible. The in vivo change in drug antibody ratio (DAR), due to deconjugation, biotransformation or other clearance phenomena, generates unique and additional challenges for ADC analysis in biological samples. Here, we report a novel hybrid approach with immuno-capture of the ADC, payload cleavage by specific enzyme, and LC-MS/MS of the cleaved payload to quantitatively measure the concentration of payload molecules still attached to the antibody via linker in plasma. The ADC reference material used for the calibration curve is not likely to be identical to the ADC measured in study samples due to the change in DAR distribution over the PK time course. The assay clearly demonstrated that there was no bias in the measurement of antibody-conjugated payload for ADC with varying DAR, which thus allowed accurate quantification even when the DAR distribution dynamically changes in vivo. This hybrid assay was fully validated based on a combination of requirements for both chromatographic and ligand binding methods, and was successfully applied to support a GLP safety study in monkeys. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:54-62. DOI:10.1016/j.jchromb.2015.08.007
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    ABSTRACT: This study describes an analytical method for bioaffinity and selectivity assessment of CXCR2 antagonists and their metabolites. The method is based on liquid chromatographic separation (LC) of metabolic mixtures followed by parallel mass spectrometry (MS) identification and bioaffinity determination. The bioaffinity is assessed using radioligand binding assays in 96-well plates after at-line nanofractionation. The described method was optimized for chemokines and low-molecular weight CXCR2 ligands. The limits of detection (LODs; injected amounts) for MK-7123, a high affinity binder to both CXCR1 and CXCR2 receptors belonging to the diaminocyclobutendione chemical class, were 40pmol in CXCR1 binding and 8pmol in CXCR2 binding. For CXCL8, the LOD was 5pmol in both binding assays. A control compound was always taken along with each bioassay plate as triplicate dose-response curve. For MK-7123, the calculated IC50 values were 314±59nM (CXCR1 binding) and 38±11nM (CXCR2 binding). For CXCL8, the IC50 values were 6.9±1.4nM (CXCR1 binding) and 2.7±1.3nM (CXCR2 binding). After optimization, the method was applied to the analysis of metabolic mixtures of eight LMW CXCR2 antagonists generated by incubation with pig liver microsomes. Moreover, metabolic profiling of the MK-7123 compound was described using the developed method. Three bioactive metabolites were found, two of which were (partially) identified. This method is suitable for bioaffinity and selectivity assessment of mixtures targeting the CXCR2. In contrary to conventional LC-MS based metabolic profiling studies done at the early lead discovery stage, additional qualitative bioactivity information of drug metabolites is obtained with the method described. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:42-53. DOI:10.1016/j.jchromb.2015.08.004
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    ABSTRACT: The aim of this study is to develop a sensitive UPLC-MS/MS method to quantify columbin in biological sample. Chromatographic separation was accomplished using Waters UPLC BEH C18 column with acetonitrile and 0.1% of formic acid in water as the mobile phases. The mass analysis was performed on an API 5500 Qtrap mass spectrometer via multiple reaction monitoring (MRM) with positive scan mood. The one-step protein precipitation by methanol was used to extract the analyte from blood samples. The results showed that the linear response range for columbin was 1.22-2,500nM. The intra and inter day variances were less than 15% and the accuracy was in acceptable range (85-115%). The analysis was done within 3.0min, and only 50μL of blood was needed. The validated method was used to determine the pharmacokinetic profile of columbin in Wistar rats, and its transport characteristics in the Caco-2 cell culture model. The results showed that columbin was poorly bioavailable (2.8% p.o. and 14% i.p.) in rats, but its transport was rapid across the Caco-2 cell monolayers, suggesting that extensive first-pass metabolism in the liver was the likely reason for its poor bioavailability. The results revealed that the validated method can be used for columbin analysis in both bioequivalent buffer and blood. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:13-18. DOI:10.1016/j.jchromb.2015.07.030
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    ABSTRACT: Delamanid (OPC-67683) is a novel nitro-dihydroimidazo-oxazole derivative that is being developed by Otsuka Pharmaceutical Co., Ltd., Japan (referred to as Otsuka hereafter) for the treatment of tuberculosis (TB). An ultra-high performance liquid chromatographic-tandem mass spectrometry (UHPLC-MS/MS) method has been developed and validated for the determination of OPC-67683 and its eight metabolites, DM-6704, DM-6705, DM-6706, DM-6717, DM-6718, DM-6720, DM-6721 and DM-6722 in human plasma to support regulated clinical development. During method development several technical challenges such as poor chromatography, separation of structural isomers, conversion of the analytes, instability in matrix and long cycle time were encountered and overcome. A protein precipitation extraction (PPE) was used to extract plasma samples (50μL) and the resulting extracts were analyzed using reversed phase UHPLC-MS/MS with a electrospray (ESI) and selected reaction monitoring (SRM). The method was fully validated over the calibration curve range of 1.00-500ng/mL for all nine analytes with linear regression and 1/x(2) weighting according to regulatory guidance for bioanalysis. Based on three inter-day precision and accuracy runs, the between-run % relative standard deviation (RSD) for all nine analytes varied from 0.0 to 11.9% and the accuracy ranged from 92.7% to 102.5% of nominal at all quality controls (QC) concentrations, including the lower limit of quantitation (LLOQ) QC at 1.00ng/mL. The extraction recovery of OPC-67683 and its eight metabolites were above 95%. Various short term and long term solution and matrix stability were established including the stability of OPC-67683 and its eight metabolites in human plasma for 708 days at -70°C. Although this method has been used to support regulated clinic studies during the last decade and over ten thousand samples have been analyzed, this is the first time that the method development process and validation data have been published. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1002:78-91. DOI:10.1016/j.jchromb.2015.07.058
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    ABSTRACT: A new quantitation method based on a multiple stable isotope dilution assay (SIDA) was developed for polyethylene glycol (PEG) homologues from PEG mixtures with average molecular weights (MW) of 400, 1500, 3000 and 4000Da in urine. Seven [(13)C4(2)H4] and two [(13)C8(2)H8]PEG homologues were synthesized and served as labelled internal standards for SIDA. PEG oligomers were resolved by reversed phase high performance liquid chromatography (RP-HPLC) coupled to mass spectrometry (MS) in multiple ion (MI) scan modus. Very low limits of detection (LODs) in a range of 0.4-12ng/mL were achieved for the single homologues. Higher PEG homologues showed increased LODs and LOQs and less effective recovery (77-87%) than PEG with lower molecular masses (95-121%). Precision (relative standard deviation) varied between 3 and 13% and showed no dependence of the chain length. The method was successfully applied to human and mice urine samples. Beside an accurate quantitation of single PEG homologues it was possible to show an alteration in the MW distribution in urine samples compared to the dosed PEG solutions. The highest MW, with which a PEG can pass the intestinal wall (so called "cut off") for humans appeared to be higher than for mice. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 08/2015; 1001:182-190. DOI:10.1016/j.jchromb.2015.07.060