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1. Real-world emission characteristics of carbonyl compounds from agricultural machines based on a portable emission measurement system

Author:
Wenhan Yu; Xianbao Shen; Bobo Wu; Lei Kong; Kaijie Xuan; Cheng Zhao; Xinyue Cao; Xuewei Hao; Xin Li; Hanyu Zhang; Zhiliang Yao
Source:
Journal of environmental sciences (China) 2023 v.124 pp. 846-859
ISSN:
1001-0742
Subject:
high performance liquid chromatography,   etc   ; acetaldehyde; acrolein; emissions factor; formaldehyde; smog pollution; tillage; China;     Show all 8 Subjects
Abstract:
... Emissions of carbonyl compounds from agricultural machines cannot be ignored. Carbonyl compounds can cause the formation of ozone (O₃) and secondary organic aerosols, which can cause photochemical smog to form. In this study, 20 agricultural machines were tested using portable emission measurement system (PEMS) under real-world tillage processes. The exhaust gases were sampled using 2,4-dinitrophe ...
DOI:
10.1016/j.jes.2022.02.031

2. Strategies to circumvent the solvent strength mismatch problem in online comprehensive two‐dimensional liquid chromatography

Author:
Soraya Chapel; Sabine Heinisch
Source:
Journal of separation science 2022 v.45 no.1 pp. 7-26
ISSN:
1615-9306
Subject:
comprehensive two-dimensional liquid chromatography; liquid chromatography,   etc   ; separation; solvents;     Show all 4 Subjects
Abstract:
... On‐line comprehensive two‐dimensional liquid chromatography is a powerful technique for the separation of highly complex samples. Due to the addition of the second dimension of separation, impressive peak capacities can be obtained within a reasonable analysis time compared to one‐dimensional liquid chromatography. In online comprehensive two‐dimensional liquid chromatography, the separation power ...
DOI:
10.1002/jssc.202100534

3. Development of a sub-hour on-line comprehensive cation exchange chromatography x RPLC method hyphenated to HRMS for the characterization of lysine-linked antibody-drug conjugates

Author:
Soraya Chapel; Florent Rouvière; Pierre Guibal; Delphine Mathieu; Sabine Heinisch
Source:
Talanta 2022 v.240 pp. 123174
ISSN:
0039-9140
Subject:
comprehensive two-dimensional liquid chromatography; reversed-phase liquid chromatography,   etc   ; cation exchange chromatography; mass spectrometry; thermal stress;     Show all 5 Subjects
Abstract:
... This study details the development of on-line two-dimensional liquid chromatography (2D-LC) methods combining cation-exchange chromatography (CEX) and reversed-phase liquid chromatography (RPLC) for the separation of the charge variants of a lysine-linked antibody-drug conjugate (ADC). This combination gives an excellent example of the potential benefits of 2D-LC approaches for the analysis of suc ...
DOI:
10.1016/j.talanta.2021.123174

4. Improving retention-time prediction in supercritical-fluid chromatography by multivariate modelling

Author:
Stef R.A. Molenaar; Mariyana V. Savova; Rebecca Cross; Paul D. Ferguson; Peter J. Schoenmakers; Bob W.J. Pirok
Source:
Journal of chromatography 2022 v.1668 pp. 462909
ISSN:
0021-9673
Subject:
liquid chromatography,   etc   ; prediction; temperature; viability;     Show all 4 Subjects
Abstract:
... The prediction of chromatographic retention under supercritical-fluid chromatography (SFC) conditions was studied, using established and novel theoretical models over ranges of modifier content, pressure and temperature. Whereas retention models used for liquid chromatography often only consider the modifier fraction, retention in SFC depends much more strongly on pressure and temperature. The via ...
DOI:
10.1016/j.chroma.2022.462909

5. Separations by Shape: Molecular Shape Recognition in Liquid Chromatography

Author:
Lane C. Sander
Source:
Chromatographia 2022 v.85 no.4 pp. 299-305
ISSN:
0009-5893
Subject:
liquid chromatography,   etc   ; molecular dynamics; spectroscopy;     Show all 3 Subjects
Abstract:
... Molecular shape can provide a basis for chromatographic separations that is distinct from other interaction mechanisms often considered in liquid chromatography. Molecular shape recognition, or shape selectivity, is most evident for the separation of isomeric compounds that have constrained molecular structures, such as polycyclic aromatic hydrocarbons. A central feature of shape-selective columns ...
DOI:
10.1007/s10337-022-04137-z

6. Identification of ‘Voodoo’: an emerging substance of abuse in Egypt

Author:
Rania Hussien; Sarah Ahmed; Hanem Awad; Maged El-Setouhy; Mohamed El-Shinawi; Jon Mark Hirshon
Source:
International journal of environmental analytical chemistry 2022 v.102 no.1 pp. 104-116
ISSN:
1029-0397
Subject:
high performance liquid chromatography; ultra-performance liquid chromatography,   etc   ; alkaloids; amphetamine; analytical chemistry; illicit drugs; tetrahydrocannabinol; youth; Egypt;     Show all 9 Subjects
Abstract:
... Background: ‘Voodoo’ is a new substance of abuse that recently spread among youth in Egypt. It has numerous potentially dangerous effects on humans. However, to date the composition of the main constituents of this compound is unknown. Purpose: We sought to identify the active components of this unknown substance”voodoo”. Methods: Three samples were collected and analysed by high-performance liqui ...
DOI:
10.1080/03067319.2020.1715384

7. Characterization of the metabolites of trans-resveratrol-3-O-glucoside in monkeys and dogs

Author:
Mei-Ying Su; Chao Dong; Ji-Yun Wan; Wen-Dong Qu; Mao-Jin Zhou
Source:
Journal of Asian natural products research 2022 v.24 no.2 pp. 179-189
ISSN:
1477-2213
Subject:
liquid chromatography,   etc   ; mass spectrometry; metabolism; metabolites; prototypes;     Show all 5 Subjects
Abstract:
... In this study, a liquid chromatography-tandem multi-stage mass spectrometry (LC/MSⁿ) method was established to characterize the metabolites of TRG in monkeys and dogs. A total of seven metabolites of TRG besides the prototype were found, which were identified as TR (M1), TRN (M2), trans-resveratrol-4'-O-glucuronide (M2'), trans-resveratrol-3-O-glucoside-4'-O-glucuronide (M3), trans-resveratrol-3-O ...
DOI:
10.1080/10286020.2021.1878157

8. Evaluation of Ion Mobility Spectrometry for Improving Constitutional Assignment in Natural Product Mixtures

Author:
Fausto Carnevale Neto; Trevor N. Clark; Norberto P. Lopes; Roger G. Linington
Source:
Journal of natural products 2022 v.85 no.3 pp. 519-529
ISSN:
1520-6025
Subject:
liquid chromatography,   etc   ; metabolites; solvents; tandem mass spectrometry;     Show all 4 Subjects
Abstract:
... The comprehensive chemical characterization of biological samples remains a central challenge in the field of natural products. Conventional workflows using liquid chromatography (LC)-coupled high-resolution tandem mass spectrometry (MS/MS or MS²) allow the detection of relevant small molecules while providing diagnostic fragment ions for their structural assignment. Still, many natural product ex ...
DOI:
10.1021/acs.jnatprod.1c01048

9. Methodology of quantitative comparison of practically achievable kinetic performance of differently structured liquid chromatography columns

Author:
Leonid M. Blumberg
Source:
Journal of chromatography 2022 v.1672 pp. 463039
ISSN:
0021-9673
Subject:
liquid chromatography,   etc   ; equations; journals; particles; permeability; width;     Show all 6 Subjects
Abstract:
... Previously introduced structural quality factor (qₘₐₓ) of LC column is a measure of its potential kinetic performance – the larger is qₘₐₓ the proportionally larger is peak capacity (nc) of isothermal and gradient analysis with the same analysis time (tₐₙₐₗ) and pressure (Δp). However, the best practically achievable column performance depends not only on qₘₐₓ, but is limited by the narrowest prac ...
DOI:
10.1016/j.chroma.2022.463039

10. Photoresponsivity of asymmetrical dihydropyrene under circularly polarized light irradiation

Author:
Tsuyoshi Sawada; Shingo Kubo; Kazuaki Nanamura
Source:
Tetrahedron letters 2022 v.100 pp. 153880
ISSN:
0040-4039
Subject:
high performance liquid chromatography,   etc   ; anisotropy; irradiation; photoisomerization;     Show all 4 Subjects
Abstract:
... Asymmetric 2,7-di-tert-butyl-10b,10c-dimethyl-2′,3′-dimethyl-pyrazino[2,3-e]dihydropyrene (DMPZ-DHP) was prepared by the annulation of diamino dihydropyrene with 2,3-butanedione. Optical resolution was achieved using chiral high-performance liquid chromatography systems after the photoisomerization of DMPZ-DHP to DMPZ-metacyclophane-diene (MCPD), and its Kuhn’s anisotropy factor (g = Δε/ε) was det ...
DOI:
10.1016/j.tetlet.2022.153880

11. Preparative chromatography behavior of palmitoleic acid on octadecyl stationary phases with different densities

Author:
Gaowa Jin; Lijie Liu; Yuanliu Yang; Yan Zhang; Ping Zhao; Dongping Yu; Yongzheng Zhou; Zhimou Guo; Hui Wang; Xinmiao Liang
Source:
Journal of separation science 2022 v.45 no.11 pp. 1866-1873
ISSN:
1615-9306
Subject:
liquid chromatography,   etc   ; palmitoleic acid; purification methods; separation;     Show all 4 Subjects
Abstract:
... The availability of various high‐purity unsaturated fatty acids has a wide range of needs due to their different activities. The nonlinear preparative chromatography behavior and principle for purification of palmitoleic acid with octadecyl bonded stationary phases were studied. The peak broadening and the concentration distribution of the target compounds were used to compare different C18 statio ...
DOI:
10.1002/jssc.202101021

12. Restoring trilinearity with the purpose of advanced modeling: towards a more effective analysis of Pericarpium Citri Reticulatae during storage periods

Author:
Yaping Li; Qing Cao; Min He; Xinyue Yang; Pingping Zeng; Weiguo Cao
Source:
Heliyon 2022 v.8 no.3 pp. e09138
ISSN:
2405-8440
Subject:
liquid chromatography,   etc   ; diodes; flavonoids; flavor; least squares;     Show all 5 Subjects
Abstract:
... To accurately quantify Pericarpium Citri Reticulatae samples, trilinear structure was restored in the stacked fingerprints for more robust modeling. Initially, liquid chromatography - diode array detector - mass spectrometry (LC-DAD-MS) and head space-solid phase micro extraction coupled to gas chromatography - mass spectrometry (HS-SPME/GC-MS) were utilized to analyze Pericarpium Citri Reticulata ...
DOI:
10.1016/j.heliyon.2022.e09138

13. A novel method for determining relative response factors using high‐performance liquid chromatography with photodiode array detector and evaporative light scattering detection

Author:
Li Zhu; Yu Zhao; Changqin Hu; Mingzhe Xu; Lihui Yin
Source:
Phytochemical analysis 2022 v.33 no.1 pp. 5-11
ISSN:
0958-0344
Subject:
high performance liquid chromatography,   etc   ; pH; phytochemicals; reference standards;     Show all 4 Subjects
Abstract:
... OBJECTIVES: Because the purity of the two impurities reference standard (RS) of cefathiamidine is not easy to obtain, HPLC‐PDA‐ELSD were used to determin the RRFs of cefathiamidine impurities. METHODS: Peak area correction was applied to calculate RRFs to eliminate the influence of different responses caused by the difference in pH between the two mobile phases of HPLC‐PDA and HPLC‐PDA‐ELSD. The r ...
DOI:
10.1002/pca.3073

14. Chiral mesostructured hydroxide zinc carbonate for enantioseparation in high performance liquid chromatography

Author:
Lin Li; Zexi Liu; Lu Han; Shunai Che; Yingying Duan
Source:
Chemical communications 2022 v.58 no.25 pp. 4040-4043
ISSN:
1364-548X
Subject:
high performance liquid chromatography,   etc   ; silica gel; zinc carbonate;     Show all 3 Subjects
Abstract:
... Chiral mesostructured hydroxide zinc carbonate coated silica gel (CMHZC@S) was prepared by a hydrothermal route using amino acids as symmetry-breaking agents. CMHZC@S with three levels of hierarchical chiralities, as a chiral stationary phase (CSP), showed enantiomeric separation ability for high performance liquid chromatography (HPLC). ...
DOI:
10.1039/d1cc06813j

15. Comprehensive two-dimensional liquid chromatographic method (Chiral × Achiral) for the simultaneous resolution of pesticides

Author:
Matías E. Díaz Merino; Agustín Acquaviva; Juan M. Padró; Cecilia B. Castells
Source:
Journal of chromatography 2022 v.1673 pp. 463126
ISSN:
0021-9673
Subject:
liquid chromatography,   etc   ; dimensions; journals; pesticides; polysaccharides; pumps; sampling;     Show all 7 Subjects
Abstract:
... This work demonstrates the potential of two-dimensional liquid chromatography (2D-LC) to increase the resolution capacity of multiple pesticides in a single analysis of samples that contain both chiral and achiral compounds. The setup is based on the combination of a chiral column in the first dimension and an achiral column in the second dimension using the on-line full comprehensive mode (LC × L ...
DOI:
10.1016/j.chroma.2022.463126

16. Practical Evaluation of Chitosan-Based Chiral Stationary Phase for Pharmaceutical Analysis by High-Performance Liquid Chromatography

Author:
Ya-Ya Gao; Shuang Liang; Wei Chen; Sheng Tang; Zheng-Wu Bai
Source:
Chromatographia 2022 v.85 no.3 pp. 247-254
ISSN:
0009-5893
Subject:
high performance liquid chromatography,   etc   ; chitosan; drugs; enantiomers; solvents;     Show all 5 Subjects
Abstract:
... In the recent years, the resolution of drug enantiomers has received widespread attention in the medical field. It is of great practical significance to develop an efficient chiral separation material for drug analysis. Based on the distinct advantages of both favorable separation performance and good solvent tolerance, chitosan bis(4-methylphenylcarbamate)-(isobutylurea) was chosen as a chiral se ...
DOI:
10.1007/s10337-022-04128-0

17. Solvent strength of aqueous phase for two typical biphasic solvent systems in high-speed countercurrent chromatography

Author:
Tingting Lin; Ping Xu; Ben Chen; Liqun Fang; Haibo You; Shengqiang Tong
Source:
Journal of chromatography 2022 v.1663 pp. 462767
ISSN:
0021-9673
Subject:
reversed-phase liquid chromatography,   etc   ; countercurrent chromatography; methanol; solvents;     Show all 4 Subjects
Abstract:
... In the present work, influence of solvent strength of aqueous phase for two frequently-used biphasic solvent system in partition coefficient (K) of selected solutes were mainly studied, and a new method for selection of biphasic solvent system was proposed for high-speed countercurrent chromatographic separations. Solvent strength was referred to the typical theory that was deeply investigated in ...
DOI:
10.1016/j.chroma.2021.462767

18. Validation of quick and highly specific quantitation method of mycotoxin in cocoa beans by high resolution multiple reaction monitoring technique for reference materials analysis

Author:
Badrul Hisyam Zainudin; Muhammad Isfaiz Iskandar; Suzannah Sharif; Aznie Aida Ahmad; Muhd Fauzi Safian
Source:
Journal of food composition and analysis 2022 v.106 pp. 104289
ISSN:
0889-1575
Subject:
liquid chromatography,   etc   ; food composition; mass spectrometry; ochratoxin A;     Show all 4 Subjects
Abstract:
... This article discussed a development, optimization, and validation of modified QuEChERS method with liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) operated in time-of-flight multiple-reaction-monitoring (TOF-MRM) mode for the analysis of ochratoxin A and aflatoxins (B₁, B₂, G₁, G₂) in cocoa beans. The recoveries for the optimized and validated method at 2 and 5 ng/g ...
DOI:
10.1016/j.jfca.2021.104289

19. Advanced analysis of oligomeric proanthocyanidins: latest approaches in liquid chromatography and mass spectrometry based analysis

Author:
Nico Symma; Andreas Hensel
Source:
Phytochemistry reviews 2022 v.21 no.3 pp. 809-833
ISSN:
1568-7767
Subject:
liquid chromatography,   etc   ; colorimetry; hydrolysis; metabolism; plant biochemistry; polymers; proanthocyanidins;     Show all 7 Subjects
Abstract:
... Proanthocyanidins (PAC) are an important and widely spread class of natural products with various bioactivities. The analytical evaluation of oligomeric and polymeric proanthocyanidins in complex extracts is still challenging, due to the complexity of structures. Nevertheless, in the last 20 years analytical techniques especially in the field of chromatography and mass spectrometry have been impro ...
DOI:
10.1007/s11101-021-09764-2

20. An emerging strategy for tracing the anti‐erectile dysfunction components of raw and salt‐processed semens of Astragali Complanati by combinatory liquid chromatography–mass spectrometry‐based quantitative analysis, efficacy assessment on impotent rats, and partial least squares regression

Author:
Jun Chen; Fei Zhu; Meiling Pan; Qing Liu; Lin Chen; Yi Tao
Source:
Journal of separation science 2022 v.45 no.11 pp. 1952-1959
ISSN:
1615-9306
Subject:
liquid chromatography,   etc   ; chloramphenicol; kaempferol; mass spectrometry; quantitative analysis; separation;     Show all 6 Subjects
Abstract:
... Semens of Astragali Complanati own anti‐erectile dysfunction effect; however, the components which contribute to the anti‐erectile dysfunction effect remain unclear. This work raised a strategy that integrates liquid chromatography coupled mass spectrometry‐based quantitative analysis, anti‐erectile dysfunction assessment on impotent rats, and their relationship analysis for pinpointing anti‐erect ...
DOI:
10.1002/jssc.202200019