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Deshpande AA, Madhavan P, Deshpande GR, Chandel RK, Yarbagi KM, Joshi AR, Moses Babu J, Murali Krishna R, Rao IM. Novel, Precise, Accurate Ion-Pairing Method to Determine the Related Substances of the Fondaparinux Sodium Drug Substance: Low-Molecular-Weight Heparin. Sci Pharm 2016; 84:19-40. [PMID: 27110496 PMCID: PMC4839259 DOI: 10.3797/scipharm.1505-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/22/2015] [Indexed: 11/29/2022] Open
Abstract
Fondaparinux sodium is a synthetic low-molecular-weight heparin (LMWH). This medication is an anticoagulant or a blood thinner, prescribed for the treatment of pulmonary embolism and prevention and treatment of deep vein thrombosis. Its determination in the presence of related impurities was studied and validated by a novel ion-pair HPLC method. The separation of the drug and its degradation products was achieved with the polymer-based PLRPs column (250 mm × 4.6 mm; 5 μm) in gradient elution mode. The mixture of 100 mM n-hexylamine and 100 mM acetic acid in water was used as buffer solution. Mobile phase A and mobile phase B were prepared by mixing the buffer and acetonitrile in the ratio of 90:10 (v/v) and 20:80 (v/v), respectively. Mobile phases were delivered in isocratic mode (2% B for 0-5 min) followed by gradient mode (2-85% B in 5-60 min). An Evaporative Light Scattering Detector (ELSD) was connected to the LC system to detect the responses of chromatographic separation. Further, the drug was subjected to stress studies for acidic, basic, oxidative, photolytic, and thermal degradations as per ICH guidelines and the drug was found to be labile in acid, base hydrolysis, and oxidation, while stable in neutral, thermal, and photolytic degradation conditions. The method provided linear responses over the concentration range of the LOQ to 0.30% for each impurity with respect to the analyte concentration of 12.5 mg/mL, and regression analysis showed a correlation coefficient value (r(2)) of more than 0.99 for all the impurities. The LOD and LOQ were found to be 1.4 µg/mL and 4.1 µg/mL, respectively, for fondaparinux. The developed ion-pair method was validated as per ICH guidelines with respect to accuracy, selectivity, precision, linearity, and robustness.
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Affiliation(s)
- Amol A. Deshpande
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - P. Madhavan
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - Girish R. Deshpande
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - Ravi Kumar Chandel
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - Kaviraj M. Yarbagi
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - Alok R. Joshi
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - J. Moses Babu
- Analytical Research, Custom Pharmaceutical Services, Dr. Reddy’s Laboratories Ltd., Bollaram road, Miyapur, Hyderabad-500049 (AP), India
| | - R. Murali Krishna
- Department of Physical, Nuclear and Chemical Oceanology, Andhra University, Visakhapatnam-530003, India
| | - I. M. Rao
- Department of Physical, Nuclear and Chemical Oceanology, Andhra University, Visakhapatnam-530003, India
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2
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Ion chromatographic separation of alkylsulphonic acids with conductivity detection. Chromatographia 2014. [DOI: 10.1007/bf02688066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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3
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Ryu HR. Determination of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) surfactant with liquid chromatography: Comparative study of evaporative light scattering detector, ultraviolet detector and conductivity detector. J Anal Sci Technol 2010. [DOI: 10.5355/jast.2010.55] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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4
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Rapid separation of desloratadine and related compounds in solid pharmaceutical formulation using gradient ion-pair chromatography. J Pharm Biomed Anal 2010; 51:146-52. [DOI: 10.1016/j.jpba.2009.08.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 08/18/2009] [Indexed: 11/22/2022]
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5
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Morvan J, Saluden M, Agasse V, Barbot F, Cardinael P, Bouillon JP, Decock G. Characterisation of ethoxylated fatty chains of anionic surfactants and determination of residual ethoxylated fatty alcohols. Anal Bioanal Chem 2006; 384:1409-15. [PMID: 16501957 DOI: 10.1007/s00216-005-0291-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2005] [Revised: 12/21/2005] [Accepted: 12/21/2005] [Indexed: 11/29/2022]
Abstract
Bachus et al. [1] recently described a new derivatisation method using 2-furoyl chloride for the characterisation of mixtures of polyethoxylated alcohols and their corresponding sulfates. This paper deals with the control of the derivatisation steps; hydrolysis and extraction conditions were optimised. The method is extended to the characterisation of alkyl sulfosuccinates, alkyl sulfoacetates and alkyl phosphates and to the analysis of residual polyethoxylated alcohols in surfactants. Extraction of non-ionic compounds using solid-phase extraction cartridges was performed before derivatisation. Residual amounts of alcohol were determined in five commercial anionic surfactants. Moreover, direct derivatisation without preliminary SPE in the same anionic surfactants proved to be efficient for dry samples.
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Affiliation(s)
- Julien Morvan
- Laboratoire Synthèse et Chromatographie, UPRES EA 3233, Sciences et Méthodes Séparatives, Université de Rouen, Rue Tesnières, 76821, Mont Saint Aignan Cedex, France
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Zahrobsky M, Camporese D, Rist Ø, Carlsen PH. HPLC analysis of aliphatic sulfonate surfactants using ion-pair detection. Molecules 2005; 10:1179-89. [PMID: 18007384 PMCID: PMC6147533 DOI: 10.3390/10091179] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Revised: 08/29/2005] [Accepted: 08/30/2005] [Indexed: 11/17/2022] Open
Abstract
A method was developed for the analysis of a number of surfactants which contained no UV-chromophores, using RP-HPLC with Indirect Photometric Detection, IPD. Pyridinium salts such as N-methylpyridinium iodide, N-methyl-2,2'-dipyridinium iodide and N,N'-dimethyl-2,2'-dipyridinium diiodide, were used as the visualization reagents, forming ion-pair complexes with the sulfonate surfactants. This allowed ordinary UV-detection. N-methylpyridinium iodide proved to be a suitable reagent, both with respect to ease of preparation and response. The eluents consisted of mixtures of acetonitrile and water, being 0.1 - 0.25 mM with respect to pyridinium salt. The method was sensitive and exhibited good signal to noise ratios, as well as linear responses over a wide concentration range. All of the analyzed surfactants were separated, including the diastereomeric forms of some of the surfactants.
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Affiliation(s)
| | | | | | - Per H.J. Carlsen
- Department of Chemistry, Norwegian University of Science and Technology, N-7491 Trondheim, Norway. Tel. 47 73 59 3968, Fax 47 73 593985
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Steiner SA, Watson DM, Fritz JS. Ion association with alkylammonium cations for separation of anions by capillary electrophoresis. J Chromatogr A 2005; 1085:170-5. [PMID: 16106865 DOI: 10.1016/j.chroma.2005.01.070] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A background electrolyte (BGE) containing a 100 mM concentration of an alkylammonium cation with ethyl, propyl or butyl groups provides an excellent medium for separation of anions by capillary electrophoresis (CE). Two major effects were noted. Use of one of a series of alkylammonium cations in the BGE at a selected pH provides a simple and effective way to vary and control electroosmotic flow (EOF) over a broad range. It is believed that the alkylammonium cations are coated onto the capillary surface through a reversible dynamic equilibrium. Secondly, alkylammonium cations modify the electrophoretic migration of sample anions and the electroosmotic migration of neutral organic analytes by association interaction. This selective interaction results in improved anion separations and permits the simultaneous separation of neutral analytes. The degree of association interaction varies with the bulk and hydrophobicity of the alkylammonium cations. Incorporation of an aliphatic amine salt of moderate molecular weight in the running electrolyte provides a valuable new way to vary the migration times of sample anions and to optimize their resolution. The interactions between alkylammonium cations and sample anions or neutral organics appear to take place entirely within the liquid phase and do not require a polymeric or micellar pseudo phase.
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Affiliation(s)
- Steven A Steiner
- Department of Chemistry and Engineering Physics, University of Wisconsin-Platteville, Platteville, WI 53818, USA
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Abstract
Methods for separation of ions by ion-exchange, ion-pair, and zwitterion ion chromatography share at least one common thread--the induced formation of a cation-anion pair in the stationary phase. Selectivity can be defined as the relative ability of sample ions to form such a pair. Examples are given in anion-exchange chromatography to show the effect of variations in the geometry, bulkiness and polarity of the resin cation on selectivity. The type of resin matrix, the hydrophobic nature of the resin surface and the degree of solvation also affect chromatographic behavior. The selectivity series observed in ion chromatography seems to be best explained by the interplay of two components: electrostatic attraction (ES) and the enforced-pairing (EP) that is brought about by hydrophobic attraction and by water-enforced ion pairing. Selectivity in ion-pair chromatography (IPC) and in zwitterion ion chromatography (ZIC) is affected by both the mobile phase cation and anion. This leads to elution orders for anions that are different from conventional ion-exchange chromatography (IC) of anions where cations are excluded from the stationary phase and have little effect on a separation. The elution order of anions in ZIC is similar to that in IC except for small anions of 2-charge, which are retained more weakly in ZIC. A unique advantage of ZIC is that sample ions can be eluted as ion pairs with pure water as the eluent and a conductivity detector. The mechanism for separation of anions on a zwitterionic stationary phase has been a subject for considerable debate. The available facts point strongly to a partitioning mechanism or a mixed mechanism in which partitioning is dominant with a weaker ion-exchange component.
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Affiliation(s)
- James S Fritz
- Department of Chemistry, Iowa State University and Ames Laboratory, Ames, IA 50011-3111, USA.
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Field JA, Sawyer TE. High-performance liquid chromatography-diode array detection of trichloroethene and aromatic and aliphatic anionic surfactants used for surfactant-enhanced aquifer remediation. J Chromatogr A 2000; 893:253-60. [PMID: 11073296 DOI: 10.1016/s0021-9673(00)00764-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A method utilizing direct aqueous injection with high-performance liquid chromatography and diode array detection (HPLC-DAD) is presented for the quantitation determination of trichloroethene (TCE) in the presence of anionic surfactants that are used to enhance the recovery of dense non-aqueous phase liquids from contaminated groundwater aquifers. The anionic surfactants investigated in this study including alkyl diphenyloxide disulfonate (Dowfax 8390) and dihexylsulfosuccinate (Aerosol MA 80-1) are used to enhance the solubility, and hence recovery, of TCE. In this type of environmental engineering application, the levels of surfactants and TCE encountered are very high (part per million to part per thousand). The anionic surfactants and TCE are quantitatively determined by direct aqueous injection onto a reversed-phase HPLC column with diode array detection. The quantitation limits of the method obtained using 100 microl injections are 0.1 mg/l for alkyl diphenyloxide disulfonates, 20 mg/l for dihexylsulfosuccinate, and 0.05 mg/l for TCE. This approach is advantageous over using gas chromatography for TCE and HPLC for the surfactants because the use of a single analytical instrument reduces sample preparation and analysis times, which increases sample throughput.
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Affiliation(s)
- J A Field
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis 97331, USA. jennifer.field@.orst.edu
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Portet FI, Treiner C, Desbène PL. Simultaneous quantitative trace analysis of anionic and nonionic surfactant mixtures by reversed-phase liquid chromatography. J Chromatogr A 2000; 878:99-113. [PMID: 10843549 DOI: 10.1016/s0021-9673(00)00225-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aim of this work was to simultaneously analyse mixtures of a polydisperse polyethylene oxide (PEO) nonionic surfactant and an anionic surfactant (sodium dodecylsulphate, SDS) in water containing sodium chloride in order to quantify trace amounts of these mixtures after their adsorption at water-solid interfaces. A fractional factorial design was then used to optimise the separation by ion-pair reversed-phase liquid chromatography as a function of six factors: the chain length of the tetraalkylammonium salt used as ion-pairing reagent which varied from methyl (C1) to n-propyl (C3); the concentration of this ion-pairing salt; the acetonitrile percentage in water used as organic modifier; the flow-rate; the temperature of analysis and also the sodium chloride concentration. The factorial design enabled in a limited number of analyses, not only to determine which factors had significant effects on retention times or on resolution between a pair of nonionic oligomers, but also to modelize and then find the interesting and rugged area where this resolution was optimal as well as the conditions where time of analysis was not prohibitive. After optimisation of HPLC analysis, we used a trace enrichment procedure to quantify very low concentrations of SDS and C12E9 polydisperse PEO in water. A C18 cartridge and a strong anionic exchange cartridge were coupled and the conditions of elution were optimised in order to obtain concentrated samples which were injected in the same eluent than the HPLC mobile phase. Under such conditions, we were able to quantify, in a single run, mixtures of anionic and nonionic surfactants at concentrations as low as 3.6 microg l(-1) for SDS and 2.5 microg l(-1) for each PEO oligomer in water.
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Affiliation(s)
- F I Portet
- Université de Rouen, Laboratoire d'Analyse des Systèmes Organiques Complexes, UPRES EA 2659, IRCOF et IFRMP, Evreux, France
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KUNIMASA H, KAMEYAMA K. Determination of N-Acyl-L-glutamates Surfactants by Capillary Electrophoresis Using Organic Modifier. ANAL SCI 1999. [DOI: 10.2116/analsci.15.451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Olson NA, Skogerboe KJ, Synovec RE. Hydrophobic interaction chromatography coupled with dynamic surface tension detection for the determination of surface active species in protein formulations. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00017-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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O'Brien AP, Cooper I, Tice PA. Correlation of specific migration (Cf) of plastics additives with their initial concentration in the polymer (Cp). FOOD ADDITIVES AND CONTAMINANTS 1997; 14:705-19. [PMID: 9373534 DOI: 10.1080/02652039709374582] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The first list of plastics additives which may be assigned restrictions in a future amendment to Directive 90/128/ EEC is likely to contain over 200 substances. If food consumption factors are taken into account many compounds on this list could have restrictions removed but there would, without doubt, still be many additives with restrictions. Extensive migration testing of food contact plastics containing restricted additives to ensure compliance would be required. These limits would be difficult to enforce, add significant cost burdens on the packaging industry and, for these reasons, may not provide improved consumer safeguards. An alternative means of control has been proposed based upon polymer composition. However, in order to support such a scheme a reliable correlation between migration of additives to their composition in the polymer must be demonstrated. There has been strong interest in establishing this relationship and a feasibility project to investigate the specific migration of four commonly used additives has been successfully completed. The study was initially funded for 1 year, by the Ministry of Agriculture, Fisheries and Food (MAFF) and industry. Analytical methods to determine the additives in food simulants have been developed and linear correlations have been demonstrated between the concentration of all four additives and their specific migration levels for each polymer studied. Experimental migration data have been compared with those generated by mathematical models.
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15
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Fakhry-Smith S, Din C, Nathoo SA, Gaffar A. Clearance of sodium lauryl sulphate from the oral cavity. J Clin Periodontol 1997; 24:313-7. [PMID: 9178110 DOI: 10.1111/j.1600-051x.1997.tb00763.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Sodium lauryl sulphate (SLS) is used in toothpaste and mouth rinses as an emulsifying and surface cleaning agent. SLS has been implicated in an increased incidence of oral irritation in subjects predisposed to recurrent aphthous stomatitis (RAU). Hence, the purpose of this study was to determine the levels of SLS found in the oral cavity following rinsing with an SLS containing mouth rinse and brushing with a SLS containing dentifrice. An analytical method to separate SLS from saliva and other complex systems was developed. The method used high performance liquid chromatography (HPLC) and detection performed using conductivity measurements. Standard curves with known concentrations showed a detection limit of less than 0.4 ug SLS/ml of fluid. 2 clinical studies were conducted to determine the amount of SLS retained in the mouth by a healthy population after rinsing or brushing with commercially available products. The results showed, after rinsing, that 96% of the available SLS from the rinse was recovered in the collected samples within 2 min. Similarly, after brushing, 86% of the SLS contained within the toothpaste was recovered from the collected samples within the first 10 min. These results showed that the amount of SLS retained in the oral cavity was minimal and the contact time between SLS and the oral cavity was very short. A 2nd study was conducted to measure the amount of SLS retained in the mouth by a population susceptible to RAU. After rinsing, 97% of the available SLS was recovered within the first 2 min. Following brushing, 89% of the SLS in the dentifrice was recovered within the first 10 min. These results were comparable to those determined by the study involving the healthy population.
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Affiliation(s)
- S Fakhry-Smith
- Colgate-Palmolive Co., Technology Center, Piscataway, NJ 08855, USA
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16
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Capillary electrophoresis of cationic surfactants with tetrazolium violet and of anionic surfactants with adenosine monophosphate and indirect photometric detection. J Chromatogr A 1996. [DOI: 10.1016/0021-9673(96)00216-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Salimi-Moosavi H, Cassidy RM. Application of Nonaqueous Capillary Electrophoresis to the Separation of Long-Chain Surfactants. Anal Chem 1996. [DOI: 10.1021/ac950813j] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hossein Salimi-Moosavi
- Chemistry Department, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - R. M. Cassidy
- Chemistry Department, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N 5C9, Canada
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18
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Ion chromatographic separation of alkylsulphonic acids with conductivity detection. Chromatographia 1995. [DOI: 10.1007/bf02318620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Stathakis C, Cassidy RM. Effect of electrolyte composition in the capillary electrophoretic separation of inorganic/organic anions in the presence of cationic polymers. J Chromatogr A 1995. [DOI: 10.1016/0021-9673(95)00150-l] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Shamsi SA, Danielson ND. Mixed-mode liquid chromatography of aliphatic anionic surfactants with a naphthalenetrisulfonate mobile phase. Chromatographia 1995. [DOI: 10.1007/bf02290352] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Chen S, Pietrzyk DJ. Reversed phase liquid chromatographic separation of linear alkylbenzenesulfonates effect of mobile phase ionic strength. J Chromatogr A 1994. [DOI: 10.1016/0021-9673(94)80223-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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23
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Chen JG, Weber SG, Glavina LL, Cantwell FF. Electrical double-layer models of ion-modified (ion-pair) reversed-phase liquid chromatography. J Chromatogr A 1993; 656:549-76. [PMID: 8113338 DOI: 10.1016/0021-9673(93)80819-t] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Stoichiometric models of ion-modified reversed-phase liquid chromatography are based on chemical equilibria between ionic modifiers and analyte. These are briefly discussed. Non-stoichiometric models portray the ionic solute as being under the summed influence of all of the ions in the system. Chromatographic theories have been developed that are based on the Poisson-Boltzmann equation, which quantitates the summed influence of the ions in the system on the solute. These ideas and quantitative predictions are described and are critically discussed.
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Affiliation(s)
- J G Chen
- Department of Chemistry, University of Pittsburgh, PA 15260
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