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Effect of phenyl numbers in polyphenyl ligand on retention properties of aromatic stationary phases. J Chromatogr A 2022; 1674:463152. [PMID: 35597197 DOI: 10.1016/j.chroma.2022.463152] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 11/23/2022]
Abstract
Aromatic phase, as one type of reversed-phase stationary phases, shows complementary selectivity to the n-alkyl counterparts especially for certain challenging separation tasks. However, effect of phenyl numbers in aromatic ligands on retention behaviors has rarely been addressed compared with the alkyl stationary phases. To illustrate the issue, a series of polyphenyl stationary phases were facially prepared via the coupling chemistry of isocyanate with amine, including aniline (π1), 4-aminobiphenyl (π2), 4-amino-p-terphenyl (π3) and [1,1':4',1'':4'',1'''-quaterphenyl]-4-amine (π4), respectively. The chromatographic behaviors of the new stationary phases as well as the traditional C18 were systematically compared in terms of retention mode, hydrophobic and aromatic selectivity, shape selectivity and π-π interaction by various analytes, including alkylbenzenes, polycyclic aromatic hydrocarbons congeners and substituted benzenes with electron-withdrawing groups. Due to the homologous structure of four polyphenyl ligands, the hydrophobic selectivity, aromatic selectivity and shape selectivity of stationary phases increase with phenyl numbers in the bonded polyphenyl ligands, whereas the increment becomes insignificant from U-π3 to U-π4. This phenomenon is explained by the insertion degree of analytes in the polyphenyl ligand brushes. Compared with the homemade C18, the polyphenyl phases indicate insignificant changes of shape selectivity with temperature. Notably, the new polyphenyl phases demonstrate the great selective separation towards the electron-deficient compounds through the π-π interaction. These findings make up for the understanding of the retention behavior of aromatic stationary phases.
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2
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Alvarez-Segura T, Torres-Lapasió JR, García-Alvarez-Coque MC. Updating chromatographic predictions by accounting ageing for single and tandem columns. J Sep Sci 2018; 41:2719-2730. [DOI: 10.1002/jssc.201800264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 04/18/2018] [Accepted: 04/26/2018] [Indexed: 11/11/2022]
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3
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Thermal pretreatments of superficially porous silica particles for high-performance liquid chromatography: Surface control, structural characterization and chromatographic evaluation. J Chromatogr A 2015; 1419:45-57. [DOI: 10.1016/j.chroma.2015.09.072] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 09/18/2015] [Accepted: 09/22/2015] [Indexed: 11/17/2022]
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4
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Yong T, Wu F, Xiao H, Wan B. Silica modified with a thiourea derivative as a new stationary phase for hydrophilic interaction liquid chromatography. J Sep Sci 2015; 38:3852-3861. [DOI: 10.1002/jssc.201500607] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/31/2015] [Accepted: 09/02/2015] [Indexed: 12/20/2022]
Affiliation(s)
- Tian Yong
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian China
| | - Fan Wu
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian China
| | - Hongbin Xiao
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian China
- Beijing University of Chinese Medicine; Beijing China
| | - Boshun Wan
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian China
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5
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Extension of the carotenoid test to superficially porous C18 bonded phases, aromatic ligand types and new classical C18 bonded phases. J Chromatogr A 2012; 1266:34-42. [DOI: 10.1016/j.chroma.2012.09.068] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Revised: 09/06/2012] [Accepted: 09/10/2012] [Indexed: 11/18/2022]
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6
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Qiu H, Mallik AK, Takafuji M, Liu X, Jiang S, Ihara H. A new imidazolium-embedded C18 stationary phase with enhanced performance in reversed-phase liquid chromatography. Anal Chim Acta 2012; 738:95-101. [DOI: 10.1016/j.aca.2012.06.018] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 06/09/2012] [Accepted: 06/10/2012] [Indexed: 11/30/2022]
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7
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Rosa PCP, Jardim ICSF. Simultaneous determination of clobutinol hydrochloride and doxylamine succinate from syrups by RP HPLC using a new stationary phase containing embedded urea polar groups. BRAZ J PHARM SCI 2012. [DOI: 10.1590/s1984-82502012000200015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new, simple, fast, reproducible and sensitive reversed phase HPLC method, using a new stationary phase containing embedded urea polar groups, has been developed and validated for the simultaneous determination of clobutinol hydrochloride (CLO) and doxylamine succinate (DOX) in syrups. The determination was carried out on a C8 urea column (125 mm x 3.9 mm i.d., 5 µm particle size) synthetized at the Liquid Chomatography Laboratory (LabCrom) of the Chemistry Institute of Unicamp. The mobile phase consisted of a mixture of acetonitrile:methanol:phosphate buffer (pH 2.5) in the gradient mode. The diode array detector (DAD) was operated at 230 nm for CLO and 262 nm for DOX. The method showed adequate precision, with relative standard deviations (RSD) less than 1%. The presence of the excipients did not interfere in the results of the analysis. Accuracy was determined by adding standards of the drugs to a placebo and good recovery values were obtained. The analytical curves were linear (r² 0.9999 for CLO and 0.9998 for DOX) over a wide concentration range (2.4-336 µg mL-1 for CLO and 2.3-63 µg mL-1 for DOX). The solutions were stable for at least 72 hours at room temperature. The criteria for validation using the ICH guidelines were fulfilled.
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8
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Mant CT, Hodges RS. Design of peptide standards with the same composition and minimal sequence variation to monitor performance/selectivity of reversed-phase matrices. J Chromatogr A 2012; 1230:30-40. [PMID: 22326185 PMCID: PMC3294100 DOI: 10.1016/j.chroma.2012.01.053] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 01/13/2012] [Accepted: 01/19/2012] [Indexed: 10/14/2022]
Abstract
The present manuscript extends our de novo peptide design approach to the synthesis and evaluation of a new generation of reversed-phase HPLC peptide standards with the same composition and minimal sequence variation (SCMSV). Thus, we have designed and synthesized four series of peptide standards with the sequences Gly-X-Leu-Gly-Leu-Ala-Leu-Gly-Gly-Leu-Lys-Lys-amide, where the N-terminal is either N(α)-acetylated (Series 1) or contains a free α-amino group (Series 3); and Gly-Gly-Leu-Gly-Gly-Ala-Leu-Gly-X-Leu-Lys-Lys-amide, where the N-terminal is either N(α)-acetylated (Series 2) or contains a free α-amino group (Series 4). In this initial study, the single substitution position, X, was substituted with alkyl side-chains (Ala
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Affiliation(s)
- Colin T. Mant
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, School of Medicine, Aurora, CO 80045, USA
| | - Robert S. Hodges
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, School of Medicine, Aurora, CO 80045, USA
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9
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Rana AA, Karim MM, Takafuji M. Synthesis, Characterization and Enhanced Selectivity in RP-HPLC of Polar Carbonyl Group Embedded Poly (Vinyl Octadecanoate) Grafted Stationary Phase by Simple Heterogeneous "Graft from" Technique. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.1.77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Characterization and optimization by experimental design of a liquid chromatographic method for the separation of hydroxylated polychlorinated biphenyls on a polar-embedded stationary phase. J Chromatogr A 2010; 1217:7231-41. [DOI: 10.1016/j.chroma.2010.09.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/08/2010] [Accepted: 09/09/2010] [Indexed: 11/19/2022]
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11
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Mant CT, Cepeniene D, Hodges RS. Reversed-phase HPLC of peptides: Assessing column and solvent selectivity on standard, polar-embedded and polar endcapped columns. J Sep Sci 2010; 33:3005-21. [DOI: 10.1002/jssc.201000518] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Poly(1-allylimidazole)-grafted silica, a new specific stationary phase for reversed-phase and anion-exchange liquid chromatography. J Chromatogr A 2009; 1216:3904-9. [DOI: 10.1016/j.chroma.2009.02.089] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Revised: 02/18/2009] [Accepted: 02/27/2009] [Indexed: 11/23/2022]
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13
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Jing LL, Jiang R, Liu P, Wang PA, Shi TY, Sun XL. Selectivity differences between alkyl and polar-modified alkyl phases in reversed phase high performance liquid chromatography. J Sep Sci 2009; 32:212-20. [PMID: 19107765 DOI: 10.1002/jssc.200800468] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Compared to conventional C18 phases, polar-modified phases have distinct differences with regards to chromatographic behavior. In the present study, ODS phases and polar-modified phases were synthesized. The columns containing these new packings demonstrated satisfactory stability under both acidic (pH 1.5) and basic (pH 10) conditions. We evaluated the selectivity differences between alkyl and polar-modified alkyl RP columns by using a range of neutral analytes. The polar-modified alkyl phases showed excellent peak shapes for almost all compounds. We also compared the selectivity differences between them for separating nucleotides by using 100% aqueous mobile phase and tricyclic antidepressants in the intermediate pH mobile phases. The results demonstrated that polar-modified phases display a significantly reduced hydrophobic nature and a significantly reduced silanol activity compared to the conventional C18 phases.
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Affiliation(s)
- Lin-Lin Jing
- Department of Chemistry, Fourth Military Medical University, Xi'an, Shaanxi, China
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14
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Zhang Y, Qu R, Sun C, Chen H, Wang C, Ji C, Yin P, Sun Y, Zhang H, Niu Y. Comparison of synthesis of chelating resin silica-gel-supported diethylenetriamine and its removal properties for transition metal ions. JOURNAL OF HAZARDOUS MATERIALS 2009; 163:127-135. [PMID: 18718715 DOI: 10.1016/j.jhazmat.2008.06.070] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 06/19/2008] [Accepted: 06/19/2008] [Indexed: 05/26/2023]
Abstract
Four kinds of silica-gel (SG)-supported diethylenetriamine (DETA) chelating resins SG-DETA-1, SG-DETA-2, SG-DETA-3, and SG-DETA-4 were prepared by functionalization of silica-gel via so-called "heterogeneous-direct-amination" (hetero-DA), "homogeneous-direct-amination" (homo-DA), "heterogeneous end-group protection" (hetero-EGP), and "homogeneous end-group protection" (homo-EGP) routes, respectively. These functionalized reactions on silica-gel were confirmed through elemental analysis, infrared spectroscopy, X-ray diffractometry, porous analysis, and thermogravimetry. Element analysis revealed that the direct-amination routes and homogeneous condition were more beneficial than the corresponding end-group protection routes and heterogeneous condition to the syntheses of chelating resins with high N content. Several metal ions, such as Ag(+), Cu(2+), Ni(2+), Hg(2+), Zn(2+) and Pb(2+), were chosen as representatives to investigate the relationship between adsorption capacities and N content of ligands onto the surface of silica-gel. The experiments results showed that all resins, SG-DETA-1, SG-DETA-2, SG-DETA-3 and SG-DETA-4, had a better adsorption for Hg(2+) and Cu(2+) than others. One conclusion should be drawn from the above compared experiments, that is, higher N content of silica-gel resins does not ensure a higher utilization ratio of N.
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Affiliation(s)
- Ying Zhang
- School of Chemistry and Materials Science, Ludong University, Yantai 264025, China
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15
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Novel reversed-phase high-performance liquid chromatography stationary phase with oligo(ethylene glycol) “click” to silica. J Chromatogr A 2008; 1191:78-82. [DOI: 10.1016/j.chroma.2007.11.093] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 11/18/2007] [Accepted: 11/20/2007] [Indexed: 11/18/2022]
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16
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Bajad SU, Lu W, Kimball EH, Yuan J, Peterson C, Rabinowitz JD. Separation and quantitation of water soluble cellular metabolites by hydrophilic interaction chromatography-tandem mass spectrometry. J Chromatogr A 2006; 1125:76-88. [PMID: 16759663 DOI: 10.1016/j.chroma.2006.05.019] [Citation(s) in RCA: 504] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 05/08/2006] [Accepted: 05/10/2006] [Indexed: 11/23/2022]
Abstract
A key unmet need in metabolomics is the ability to efficiently quantify a large number of known cellular metabolites. Here we present a liquid chromatography (LC)-electrospray ionization tandem mass spectrometry (ESI-MS/MS) method for reliable measurement of 141 metabolites, including components of central carbon, amino acid, and nucleotide metabolism. The selected LC approach, hydrophilic interaction chromatography with an amino column, effectively separates highly water soluble metabolites that fail to retain using standard reversed-phase chromatography. MS/MS detection is achieved by scanning through numerous selected reaction monitoring events on a triple quadrupole instrument. When applied to extracts of Escherichia coli grown in [12C]- versus [13C]glucose, the method reveals appropriate 12C- and 13C-peaks for 79 different metabolites.
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Affiliation(s)
- Sunil U Bajad
- Lewis-Sigler Institute for Integrative Genomics and Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
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17
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Silva RB, Silva CR, Airoldi C, Collins CH, Jardim ICS. Preparation and characterization of a new HPLC C18 reversed phase containing thiocarbamate groups. Microchem J 2006. [DOI: 10.1016/j.microc.2006.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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Ohyama K, Fujimoto E, Wada M, Kishikawa N, Ohba Y, Akiyama S, Nakashima K, Kuroda N. Investigation of a novel mixed-mode stationary phase for capillary electrochromatography. Part III: Separation of nucleosides and nucleic acid bases on sulfonated naphthalimido-modified silyl silica gel. J Sep Sci 2005; 28:767-73. [PMID: 15938185 DOI: 10.1002/jssc.200500030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Capillary electrochromatography (CEC) with a novel stationary phase, 3-(4-sulfo-1,8-naphthalimido)propyl-modified silyl silica gel (SNAIP), proved useful for the separation of nucleosides and nucleic acid bases. The application scope of SNAIP, which is a relatively polar reversed-phase (RP)-type stationary phase, was successfully expanded to include the CEC separation of polar compounds although the combination of non-polar RP phase with highly aqueous mobile phase is often inadequate. Due to the permanently charged sulfonic acid groups and the naphthalimidopropyl moiety, the retention of charged and relatively polar nucleosides as well as bases on the SNAIP stationary phase was effected by electrostatic and hydrophobic interactions. This yielded a unique selectivity on SNAIP toward nucleosides and bases. The characteristic EOF on SNAIP, which was stronger at higher aqueous content in the mobile phase, proved suitable for the separation of polar compounds in reversed-phase mode with highly aqueous mobile phase. In addition, when a double stepwise gradient was employed to accelerate the latest peak (adenine), the elution time was shortened to less than half its original duration.
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Affiliation(s)
- Kaname Ohyama
- Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, Nagasaki, Japan
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19
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Ohyama K, Fujimoto E, Wada M, Kishikawa N, Ohba Y, Akiyama S, Nakashima K, Kuroda N. Investigation of a novel mixed-mode stationary phase for capillary electrochromatography. Part III1): Separation of nucleosides and nucleic acid bases on sulfonated naphthalimido-modified silyl silica gel. J Sep Sci 2005. [DOI: 10.1002/jssc.200400030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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20
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Jardim ICS, Collins KE, Collins CH. Immobilized polysiloxanes as stationary phases for high-performance liquid chromatography and solid phase extraction. Microchem J 2004. [DOI: 10.1016/j.microc.2004.02.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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21
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Horak J, Maier NM, Lindner W. Investigations on the chromatographic behavior of hybrid reversed-phase materials containing electron donor–acceptor systems. J Chromatogr A 2004; 1045:43-58. [PMID: 15378878 DOI: 10.1016/j.chroma.2004.05.096] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The chromatographic behavior of three naphthalimide-type stationary phases were elucidated in terms of hydrophobic, silanophilic and pi-pi interaction properties, employing besides common chromatographic column test methods from Engelhardt and Tanaka, also new test mixtures of geometrical and functional aromatic isomers. It was found that the presence of electron donor/acceptor moieties within a reversed phase system did not only increase the overall retention times for aromatic solutes, but also lead to an enhanced shape selectivity of the hybrid stationary phase. In this context, shape discrimination is primarily based on the number of accessible pi-electrons for pi-pi interaction with the embedded electron deficient ligand moieties. The most outstanding results were obtained for the 1,4,5,8-naphthalenediimidic selector with its horizontal arrangement on the silica surface, which enables a direct face-to-face pi-pi interaction with aromatic solutes, with only little hydrophobic contribution.
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Affiliation(s)
- Jeannie Horak
- Institute of Analytical Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna, Austria
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22
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Sales JA, Faria FP, Prado AG, Airoldi C. Attachment of 2-aminomethylpyridine molecule onto grafted silica gel surface and its ability in chelating cations. Polyhedron 2004. [DOI: 10.1016/j.poly.2003.11.051] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Silva CR, Collins CH, Jardim ICSF, Airoldi C. Chromatographic and column stability at pH 7 of a C18 dimethylurea polar stationary phase. J Chromatogr A 2004; 1030:157-66. [PMID: 15043265 DOI: 10.1016/j.chroma.2003.11.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Chromatographic evaluations of a C18 dimethylurea phase in 150 mm x 3.9 mm HPLC columns were performed using the Tanaka and Engelhardt test mixtures. The applicability of the new C18 dimethylurea phase was also evaluated with a mixture of some herbicides and their metabolites. An artificial aging procedure was also performed by passing a potassium phosphate mobile phase buffered at pH 7.0 through C18 50 mm x 3.9 mm dimethylurea columns. The column stability was evaluated by means of the chromatographic parameters obtained for the separation of some compounds from the Neue test mixture, using apolar, polar and highly basic analytes.
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Affiliation(s)
- César Ricardo Silva
- Instituto de Química, Universidade Estadual de Campinas, Caixa Postal 6154, 13083-970 Campinas, São Paulo, Brazil
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Lopes NP, Collins KE, Jardim ICSF. Microwave-immobilized polybutadiene stationary phase for reversed-phase high-performance liquid chromatography. J Chromatogr A 2004; 1030:225-9. [PMID: 15043273 DOI: 10.1016/j.chroma.2003.09.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Polybutadiene (PBD) has been immobilized on high-performance liquid chromatography (HPLC) silica by microwave radiation at various power levels (52-663 W) and actuation times (3-60 min). Columns prepared from these reversed-phase HPLC materials, as well as from similar non-irradiated materials, were tested with standard sample mixtures and characterized by elemental analysis (%C) and infrared spectroscopy. A microwave irradiation of 20 min at 663 W gives a layer of immobilized PBD that presented good performance. Longer irradiation times give thicker immobilized layers having less favorable chromatographic properties.
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Affiliation(s)
- Nilva P Lopes
- Laboratório de Pesquisas em Cromatografia Líquida, LABCROM, Instituto de Química, Universidade Estadual de Campinas, Caixa Postal 6154, CEP 13084-971 Campinas, SP, Brazil
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25
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Anchored fibrous chrysotile silica and its ability in using nitrogen basic centers on cation complexing from aqueous solution. Colloids Surf A Physicochem Eng Asp 2003. [DOI: 10.1016/s0927-7757(03)00421-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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