401
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Fernández-Pérez V, Luque de Castro MD. Micelle formation for improvement of continuous subcritical water extraction of polycyclic aromatic hydrocarbons in soil prior to high-performance liquid chromatography-fluorescence detection. J Chromatogr A 2000; 902:357-67. [PMID: 11192168 DOI: 10.1016/s0021-9673(00)00770-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new method for the extraction-individual separation-determination of polycyclic aromatic hydrocarbons (PAHs) in soil is reported. The method is based on the integration of three steps: continuous subcritical extraction, solid-phase clean-up/preconcentration, and HPLC separation with post-column fluorimetric determination. Sodium dodecyl sulfate (SDS) was added to the water for favouring the extractability of the low-polarity analytes. Soil samples spiked with the target PAHs were subjected to static-dynamic extraction with SDS-water at 50 bar, 150 degrees C, for 15 min of static extraction and 10 min dynamic extraction at a flow-rate of 3 ml/min. Recoveries from 73.6 to 110.4% were obtained in the presence of SDS versus 30 to 80% obtained with water as extractant. The calibration graphs provided by HPLC-fluorimetric detection were run between 0.031 and 0.375 microg/ml for each analyte with regression coefficients between 0.917 and 0.999 and precision, expressed as RSD, between 1.2 and 11.5%. The method was applied to a certified reference material [CRM 524, BCR (Community Bureau of Reference), industrial soil/organic] for validation and the results obtained were in agreement with the certified values.
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402
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Rukhadze MD, Tsagareli SK, Sidamonidze NS, Meyer VR. Cloud-point extraction for the determination of the free fraction of antiepileptic drugs in blood plasma and saliva. Anal Biochem 2000; 287:279-83. [PMID: 11112274 DOI: 10.1006/abio.2000.4863] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A method for the determination of the free fraction of antiepileptic drugs in plasma and saliva was developed. The separation of free and protein-bound fractions was obtained by cloud-point extraction under optimum conditions of pH, surfactant type, and concentration. It is shown that the free fraction of carbamazepine and of phenobarbital in plasma coincides with the drug concentration in saliva. The dependence of the free fraction in plasma on the administered dose was studied. The influence of the simultaneous administration of the two drugs on their free concentrations was revealed: In the presence of carbamazepine the free fraction of phenobarbital is decreased markedly whereas phenobarbital does not influence the behavior of carbamazepine.
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Affiliation(s)
- M D Rukhadze
- Department of Chemistry, Tbilisi State University, Chavchavadze ave. 3, Tbilisi, 380028, Georgia.
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403
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Carabias-Martínez R, Rodríguez-Gonzalo E, Moreno-Cordero B, Pérez-Pavón JL, García-Pinto C, Fernández Laespada E. Surfactant cloud point extraction and preconcentration of organic compounds prior to chromatography and capillary electrophoresis. J Chromatogr A 2000; 902:251-65. [PMID: 11192158 DOI: 10.1016/s0021-9673(00)00837-2] [Citation(s) in RCA: 321] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The use of preconcentration steps based on phase separation by the cloud point technique offers a convenient alternative to more conventional extraction systems. It has been used successfully for the preconcentration of species of widely differing character and nature, such as metal ions, proteins and other biomaterials, or organic compounds of strongly differing polarity. Here we address the most recent analytical applications of this methodology when used as an isolation and trace enrichment step prior to the analysis of organic compounds (polycyclic aromatic hydrocarbons, polychlorinated compounds, pesticides, phenolic derivatives, aromatic amines, vitamins, etc.) via liquid and gas chromatography or capillary electrophoresis.
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Affiliation(s)
- R Carabias-Martínez
- Department of Analytical Chemistry, Nutrition and Food Sciences, School of Chemistry, University of Salamanca, Spain.
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404
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Affiliation(s)
- Sang Beom Lee
- Inorganic Chemistry Laboratory Korea Institute of Science and Technology Seoul 130-650, Korea Department of Chemistry, Korea University Seoul 136-701, Korea
| | - Soo-Chang Song
- Inorganic Chemistry Laboratory Korea Institute of Science and Technology Seoul 130-650, Korea Department of Chemistry, Korea University Seoul 136-701, Korea
| | - Jung-Il Jin
- Inorganic Chemistry Laboratory Korea Institute of Science and Technology Seoul 130-650, Korea Department of Chemistry, Korea University Seoul 136-701, Korea
| | - Youn Soo Sohn
- Inorganic Chemistry Laboratory Korea Institute of Science and Technology Seoul 130-650, Korea Department of Chemistry, Korea University Seoul 136-701, Korea
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405
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Szymanowski J, Apostoluk W. Estimation of Distribution Parameters of Organic Solutes in Cloud Point Extraction. J Colloid Interface Sci 2000; 228:178-181. [PMID: 10882508 DOI: 10.1006/jcis.2000.6896] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cloud point extraction of aromatic solutes in the system containing nonionic surfactant polyoxyethylene nonylphenyl ether (PONPE 10) was discussed in terms of their hydrogen-bond donating and accepting abilities and hydrophobicity. It was shown that the Abraham model could be used to estimate the distribution ratio and the effect of aromatic solutes on the cloud point. Copyright 2000 Academic Press.
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Affiliation(s)
- J Szymanowski
- Institute of Chemical Technology and Engineering, Poznan University of Technology, Pl. M. Sklodowskiej-Curie 2, Poznan, 60-965, Poland
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406
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407
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Xiao JX, Sivars U, Tjerneld F. Phase behavior and protein partitioning in aqueous two-phase systems of cationic--anionic surfactant mixtures. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 743:327-38. [PMID: 10942303 DOI: 10.1016/s0378-4347(00)00214-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cationic-anionic surfactant mixtures can form aqueous two-phase systems. Such aqueous surfactant two-phase systems (ASTP systems) can be used for separation and purification of biomaterials. In this work we investigated the phase behavior and the partitioning of BSA and lysozyme in the ASTP system formed by mixtures of dodecyltriethylammonium bromide and sodium dodecylsulfate (SDS). The pseudo ternary phase diagram of these mixtures at low total surfactant concentrations contains two narrow two-phase regions, which represent two kinds of different ASTP systems formed when cationic and anionic surfactants are in excess, respectively (called ASTP-C and ASTP-A). The phase separation is associative, one phase is surfactant-rich, and the other phase is surfactant-depleted. Mechanisms behind the phase behavior are discussed. The phase behavior, especially phase separation time and phase volume ratio, is strongly influenced by total concentration and molar ratio of mixed surfactants. The effect of molar ratio is strong, which enables one to get desired phase systems also at very low total concentration by tuning the molar ratio of the surfactants. It was shown that the marked differences of surfactant concentration between the phases makes proteins distribute with different partitioning coefficients. The charges on the micellar surface, which can be adjusted by tuning the molar ratio of cationic surfactants to anionic surfactants, enhance the selectivity of protein partitioning by electrostatic effects. At pH 7.1, in the ASTP-C systems, negatively charged BSA is concentrated in the surfactant-rich phase and positively charged lysozyme in the surfactant-depleted phase, while in ASTP-A systems, a totally opposite partitioning was observed. It was shown that lysozyme could retain activity in ASTP systems.
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Affiliation(s)
- J X Xiao
- Department of Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, Sweden
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408
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Sivars U, Abramson J, Iwata S, Tjerneld F. Affinity partitioning of a poly(histidine)-tagged integral membrane protein, cytochrome bo3 ubiquinol oxidase, in a detergent--polymer aqueous two-phase system containing metal-chelating polymer. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 743:307-16. [PMID: 10942301 DOI: 10.1016/s0378-4347(00)00113-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A system has been developed for selective partitioning of membrane proteins. For the first time, an integral membrane protein, cytochrome bo3 ubiquinol oxidase from Escherichia coli, has been affinity partitioned in an aqueous two-phase system. The systems used were different detergent/polymer aqueous two-phase systems containing a metal-chelating polymer, such as poly(ethyleneglycol)-iminodiacetic acid-Cu(II) as well as dextran-iminodiacetic acid-Cu(II). Many non-ionic detergents, such as alkyl(polyethyleneoxide) (CmEOn), Triton, Tween and alkylglucosides, form two-phase systems in mixture with polymers, such as dextran and poly(ethyleneglycol), i.e., a micelle-enriched phase in equilibrium with a polymer-enriched phase are formed. In general, membrane proteins partition strongly to the micelle phase. We show that it is possible to selectively partition a poly(histidine)-tagged integral membrane protein into the polymer phase by metal affinity partitioning, with a shift in the partitioning coefficient from 0.015 to 4.8 (300-fold). The affinity partitioning was characterized and the effects of ligand concentration, pH, time, salts, buffer type, imidazole and charged detergent are discussed. Thus, a fast and mild affinity procedure for the purification of integral membrane proteins can be developed in affinity detergent/polymer aqueous two-phase systems, and the method is especially suitable for the purification of labile integral membrane proteins, such as receptors.
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Affiliation(s)
- U Sivars
- Department of Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, Sweden
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409
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Fricke B. Quantitative determination of zwitterionic detergents using salt-induced phase separation of Triton X-100. Anal Biochem 2000; 281:144-50. [PMID: 10870829 DOI: 10.1006/abio.2000.4552] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Zwitterionic detergents interfere with the salt-induced phase separation for nonionic detergents in a concentration-dependent manner by shifting the normal cloud point of nonionic detergents to a higher ionic strength at room temperature. This phenomenon was used to determine the concentration of the zwitterionic detergents CHAPS, CHAPSO, and sulfobetaine SB-12 in solution by titration with ammonium sulfate in the presence of Triton X-100. Among the ionic detergents tested, the method was only applicable to sodium cholate. The assay can be used to control the removal of zwitterionic detergents during the reconstitution of membrane proteins in liposomes. However, it cannot be used to determine the specific binding of zwitterionic detergents to highly diluted, pure membrane proteins because of the limited sensitivity. Neither proteins nor phospholipids interfered with this method at concentrations up to 20 mg/ml of test solution (human serum albumin) or 10 mg/ml (phospholipids), respectively. Since the assay is based on the competition between salts and nonionic detergents for water molecules, it is important to equalize the ionic strength of samples and calibration standards.
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Affiliation(s)
- B Fricke
- Institute for Physiological Chemistry, Medical Faculty, Martin Luther University, Halle, Germany.
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410
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Saitoh T, Matsudo T, Matsubara C. Micelle-mediated extraction for concentrating hydrophobic organic compounds. J Chromatogr A 2000; 879:121-8. [PMID: 10893028 DOI: 10.1016/s0021-9673(00)00345-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An extraction method based on polymer-induced phase separation of aqueous micellar solutions of octyl-beta-D-thioglucoside (OTG) was assessed for concentrating hydrophobic analytes. Various hydrophobic compounds such as polycyclicaromatic hydrocarbons, alkylbenzenes, alkylphenols, chlorobenzenes, chlorophenols, phthalic esters, pesticides, and steroid hormones could be efficiently concentrated into a small volume of surfactant-rich phase, while hydrophilic matrix components remained in the bulk aqueous phase. The surfactant-rich phase containing concentrated OTG could be directly introduced into the hygro-organic mobile phase of high-performance liquid chromatography with ultra-violet photometric detection. The application of this method greatly enhanced the signal intensity in the chromatogram while reducing the interference of matrix components.
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Affiliation(s)
- T Saitoh
- Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Japan.
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411
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Shin M, Umebayashi Y, Kanzaki R, Ishiguro S. Formation of Copper(II) Thiocyanato and Cadmium(II) Iodo Complexes in Micelles of Nonionic Surfactants with Varying Poly(ethylene oxide) Chain Lengths. J Colloid Interface Sci 2000; 225:112-118. [PMID: 10767151 DOI: 10.1006/jcis.2000.6722] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Formation of copper(II) thiocyanato and cadminum(II) iodo complexes in micelles of poly(ethylene oxide) (PEO)-type nonionic surfactants with varying PEO chain lengths of 9.5 (Triton X-100), 30 (Triton X-305), and 40 (Triton X-405) has been studied by titration spectrophotometry and calorimetry at 298 K. In a given surfactant solution, all data obtained were analyzed by assuming formation of ternary complexes MX(n)Y(m)((2-n)+) (M = Cu(II),Cd(II); X = SCN(-), I(-); Y = surfactant), and the complexes thus form in aqueous phase (m = 0) or in micelles (m = 1). In the Cu(II)-SCN(-) system, spectrophotometric data obtained by varying concentrations of the surfactant can be explained well in terms of formation of Cu(NCS)(2)Y in micelles and Cu(NCS)(+) and Cu(NCS)(2) in an aqueous phase, and it turned out that formation constant of Cu(NCS)(2)Y increases with increasing PEO chain length. In the Cd(II)-I(-) system, the formation of CdI(3)Y(-) and CdI(4)Y(2-) is concluded in micelles, and that of CdI(+), CdI(3)(-), and CdI(4)(2-) in an aqueous phase. Interestingly, formation enthalpies of CdI(3)Y(-) and CdI(4)Y(2-) become significantly less negative with increasing PEO chain length. This suggests that transfer of the complexes from aqueous solution to a hydrophobic octylphenyl (OP) moiety in micelles is significantly more exothermic than that to a hydrophilic PEO one. Thermodynamic parameters of transfer of CdI(3)(-) and CdI(4)(2-) from aqueous solution to the OP and PEO moieties of micelles have been evaluated. Copyright 2000 Academic Press.
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Affiliation(s)
- M Shin
- Department of Chemistry, Faculty of Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan
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412
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Crick EW, Conte ED. Alkyltrimethylammonium surfactant-mediated extractions: characterization of surfactant-rich and aqueous layers, and extraction performance. J Chromatogr A 2000; 877:87-93. [PMID: 10845791 DOI: 10.1016/s0021-9673(00)00194-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Most surfactants employed for extraction purposes contain strongly absorbing chromophores, and therefore cannot be used with the ultraviolet-visible HPLC detector because of the high background created. Alkyltrimethylammonium surfactants, which do not have strongly absorbing chromophores, have shown promise as an extractant compatible with HPLC-ultraviolet-visible detection. In our extraction procedure, alkyltrimethylammonium surfactants are added to a sample containing organic analytes in distilled water. Sodium chloride is next added, then the entire sample is shaken. Before centrifugation, 1-octanol is added to aid in the two phase formation of surfactant-rich and aqueous phases. In this paper, we present the results of our studies on the extraction behavior of an alkyltrimethylammonium surfactant technique using various organic compounds as test probes. Specifically studied are the extraction behavior of organic bases, isomers of varying polarity and a zwitterionic species that has different charges at various pH values. Results from multiple extractions to obtain quantitative recovery of analytes is also presented. The composition of each phase is elucidated through the interpretation of data obtained from thermogravimetric and carbon, hydrogen and nitrogen (CHN) instrumentation.
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Affiliation(s)
- E W Crick
- Department of Chemistry, Western Kentucky University, Bowling Green 42101, USA
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413
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Sivars U, Tjerneld F. Mechanisms of phase behaviour and protein partitioning in detergent/polymer aqueous two-phase systems for purification of integral membrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1474:133-46. [PMID: 10742592 DOI: 10.1016/s0304-4165(99)00208-1] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Detergent/polymer aqueous two-phase systems are studied as a fast, mild and efficient general separation method for isolation of labile integral membrane proteins. Mechanisms for phase behaviour and protein partitioning of both membrane-bound and hydrophilic proteins have been examined in a large number of detergent/polymer aqueous two-phase systems. Non-ionic detergents such as the Triton series (polyoxyethylene alkyl phenols), alkyl polyoxyethylene ethers (C(m)EO(n)), Tween series (polyoxyethylene sorbitol esters) and alkylglucosides form aqueous two-phase systems in mixtures with hydrophilic polymers, such as PEG or dextran, at low and moderate temperatures. Phase diagrams for these mixtures are shown and phase behaviour is discussed from a thermodynamic model. Membrane proteins, such as bacteriorhodopsin and cholesterol oxidase, were partitioned strongly to the micelle phase, while hydrophilic proteins, BSA and lysozyme, were partitioned to the polymer phase. The partitioning of membrane protein is mainly determined by non-specific hydrophobic interactions between detergent and membrane protein. An increased partitioning of membrane proteins to the micelle phase was found with an increased detergent concentration difference between the phases, lower polymer molecular weight and increased micelle size. Partitioning of hydrophilic proteins is mainly related to excluded volume effects, i.e. increased phase component size made the hydrophilic proteins partition more to the opposite phase. Addition of ionic detergent to the system changed the partitioning of membrane proteins slightly, but had a strong effect on hydrophilic proteins, and can be used for enhanced separation between hydrophilic proteins and membrane protein.
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Affiliation(s)
- U Sivars
- Department of Biochemistry, Centre for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, S-221 00, Lund, Sweden
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414
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MacLachlan J, Wotherspoon AT, Ansell RO, Brooks CJ. Cholesterol oxidase: sources, physical properties and analytical applications. J Steroid Biochem Mol Biol 2000; 72:169-95. [PMID: 10822008 DOI: 10.1016/s0960-0760(00)00044-3] [Citation(s) in RCA: 201] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Since Flegg (H.M. Flegg, An investigation of the determination of serum cholesterol by an enzymatic method, Ann. Clin. Biochem. 10 (1973) 79-84) and Richmond (W. Richmond, The development of an enzymatic technique for the assay of cholesterol in biological fluids, Scand. J. clin. Lab. Invest. 29 (1972) 25; W. Richmond, Preparation and properties of a bacterial cholesterol oxidase from Nocardia sp. and its application to enzyme assay of total cholesterol in serum, Clinical Chemistry 19 (1973) 1350-1356) first illustrated the suitability of cholesterol oxidase (COD) for the analysis of serum cholesterol, COD has risen to become the most widely used enzyme in clinical laboratories with the exception of glucose oxidase (GOD). The use is widespread because assays incorporating the enzyme are extremely simple, specific, and highly sensitive and thus offer distinct advantages over the Liebermann-Burchard analytical methodologies which employ corrosive reagents and can be prone to unreliable results due to interfering substances such as bilirubin. Individuals can now readily determine their own serum cholesterol levels with a simple disposable test kit. This review discusses COD in some detail and includes the topics: (1) The variety of bacterial sources available; (2) The various extraction/purification protocols utilised in order to obtain protein of sufficient clarification (purity) for use in food/clinical analysis; (3) Significant differences in the properties of the individual enzymes; (4) Substrate specificities of the various enzymes; (5) Examples of biological assays which have employed cholesterol oxidase as an integral part of the analysis, and the various assay protocols; (6) New steroidal products of COD. This review is not a comprehensive description of published work, but is intended to provide an account of recent and current research, and should promote further interest in the application of enzymes to analytical selectivity.
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Affiliation(s)
- J MacLachlan
- Department of Physical Sciences, Glasgow Caledonian University, City Campus, 70 Cowcaddens Road, Glasgow, UK.
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415
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Pino V, Ayala JH, Afonso AM, González V. Determination of polycyclic aromatic hydrocarbons in marine sediments by high-performance liquid chromatography after microwave-assisted extraction with micellar media. J Chromatogr A 2000; 869:515-22. [PMID: 10720265 DOI: 10.1016/s0021-9673(99)01220-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A simple and rapid method is developed for extraction and determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. The procedure was based on the microwave-assisted extraction of PAHs in marine sediment samples using a micellar medium of Polyoxyethylene 10 lauryl ether as extractant. Two-level factorial designs have been used to optimize the microwave extraction process. The analysis of extracts has been carried out by HPLC with UV detection. Fortified sediments gave an average recovery between 85.70 and 100.73%, with a relative standard deviation of 1.77-7.0% for PAHs with a ring number higher than three.
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Affiliation(s)
- V Pino
- Department of Analytical Chemistry, Nutrition and Food Science, University of La Laguna, Spain
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416
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KIMCHUWANIT WAROPHAT, OSUWAN SOMCHAI, SCAMEHORN JOHNF, HARWELL JEFFREYH, HALLER KENNETHJ. Use of a Micellar-Rich Coacervate Phase to Extract Trichloroethylene from Water. SEP SCI TECHNOL 2000. [DOI: 10.1081/ss-100102085] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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417
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Jin G, Kan J, Zhu Y, Lei N, Chen B. Spectrophotometric determination of the total amount of rare-earth after solid–liquid extractive preconcentration with polyvinyl alcohol condensed p-formylchlorophosphonazo. Microchem J 2000. [DOI: 10.1016/s0026-265x(99)00025-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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418
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McCarroll ME, Joly AG, Wang Z, Friedrich DM. Time-Resolved Fluorescence Anisotropies in Mixed Surfactant Solutions. J Colloid Interface Sci 1999; 218:260-264. [PMID: 10489299 DOI: 10.1006/jcis.1999.6414] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Time-resolved fluorescence anisotropy decays of solutions of Triton X-114 (TX-114) with various amounts of sodium dodecyl sulfate (SDS) were measured using the emission both from the surfactant itself and from added perylene. In the former case, the monomer and aggregate species of the surfactant were spectroscopically isolated and were shown to have significantly different rotational correlation times. The rotational diffusion of perylene in micellar TX-114 with small amounts of added SDS appeared to have a component with a very short correlation time. The anisotropy decay curves showed the existence of limiting anisotropies (r(infinity)), indicating hindered probe rotation in the micellar environment. At higher SDS concentrations, the fast-decaying component slowed down and the limiting anisotropy decreased substantially, suggesting some migration of the probe to the interior of the micelle. Copyright 1999 Academic Press.
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Affiliation(s)
- ME McCarroll
- Environmental and Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington, 99352
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419
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Quina FH, Hinze WL. Surfactant-Mediated Cloud Point Extractions: An Environmentally Benign Alternative Separation Approach. Ind Eng Chem Res 1999. [DOI: 10.1021/ie980389n] [Citation(s) in RCA: 333] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Frank H. Quina
- Department of Chemistry, Wake Forest University, P.O. Box 7486, Winston-Salem, North Carolina 27109
| | - Willie L. Hinze
- Department of Chemistry, Wake Forest University, P.O. Box 7486, Winston-Salem, North Carolina 27109
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420
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Saitoh T, Yoshida Y, Matsudo T, Fujiwara S, Dobashi A, Iwaki K, Suzuki Y, Matsubara C. Concentration of Hydrophobic Organic Compounds by Polymer-Mediated Extraction. Anal Chem 1999. [DOI: 10.1021/ac990478p] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tohru Saitoh
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Yuki Yoshida
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Toshiyuki Matsudo
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Shinsuke Fujiwara
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Akira Dobashi
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Kazuo Iwaki
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Yasuzo Suzuki
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
| | - Chiyo Matsubara
- School of Pharmacy and School of Life Science, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan, Center for Technology Development, Ebara Research Co., Ltd., Fujisawa, 251-8502, Japan, and National Institute of Material and Chemical Research, Tsukuba 305-8567, Japan
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421
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Carabias-Martínez R, Rodríguez-Gonzalo E, Domínguez-Alvarez J, Hernández-Méndez J. Cloud Point Extraction as a Preconcentration Step Prior to Capillary Electrophoresis. Anal Chem 1999; 71:2468-74. [DOI: 10.1021/ac9812227] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R. Carabias-Martínez
- Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, 37008 Salamanca, Spain
| | - E. Rodríguez-Gonzalo
- Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, 37008 Salamanca, Spain
| | - J. Domínguez-Alvarez
- Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, 37008 Salamanca, Spain
| | - J. Hernández-Méndez
- Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, 37008 Salamanca, Spain
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422
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Tong AJ, Dong JJ, Li LD. Aqueous two-phase extraction system of sodium perfluorooctanoate and dodecyltriethylammonium bromide mixture and its application to porphyrins and dyes. Anal Chim Acta 1999. [DOI: 10.1016/s0003-2670(99)00129-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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423
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Huddleston JG, Willauer HD, Griffin ST, Rogers RD. Aqueous Polymeric Solutions as Environmentally Benign Liquid/Liquid Extraction Media. Ind Eng Chem Res 1999. [DOI: 10.1021/ie980505m] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Heather D. Willauer
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487
| | - Scott T. Griffin
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487
| | - Robin D. Rogers
- Department of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487
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424
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425
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Synthesis and characterisation of 8-hydroxyquinoline–bovine serum albumin conjugates as metal ion chelating proteins. Anal Chim Acta 1999. [DOI: 10.1016/s0003-2670(98)00624-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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426
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Wu YC, Huang SD. Cloud point preconcentration and liquid chromatographic determination of aromatic amines in dyestuffs. Anal Chim Acta 1998. [DOI: 10.1016/s0003-2670(98)00393-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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427
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Kabin JA, Tolstedt SL, Sáez AE, Grant CS, Carbonell RG. Removal of Organic Films From Rotating Disks Using Aqueous Solutions of Nonionic Surfactants: Effect of Surfactant Molecular Structure. J Colloid Interface Sci 1998; 206:102-111. [PMID: 9761633 DOI: 10.1006/jcis.1998.5689] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In prior work, we examined the removal of abietic acid films from rotating fiberglass laminate disks by aqueous solutions of a nonionic surfactant. A three-stage cleaning mechanism was found, consisting successively of solubilization, shear-driven cleaning, and roll-up. We extend this work by exploring the influence of the surfactant molecular structure on the kinetics of the cleaning process. Five different poly(ethylene glycol) alkyl ether surfactants (CxEy) were used. Both the alkyl (x) and ethoxy (y) chain lengths were varied. Not all of the surfactants exhibited a three-stage cleaning mechanism. It was found that for surfactants with relatively high solubilization rates, the shear-driven cleaning stage did not occur. The selection of the most efficient surfactant depends on whether the surfactant concentration is below or above its critical micelle concentration (CMC). At submicellar concentrations, faster cleaning is obtained by surfactants that can induce shear-driven removal. At concentrations above the CMC, it is found that surfactant efficiency for a fixed alkyl or ethoxy chain length increases as the surfactant becomes more hydrophilic. This is attributed in part to the lower viscosity that the film achieves with the more hydrophilic surfactants due to their partitioning into the film, as well as their ability to carry water into the film. Copyright 1998 Academic Press.
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Affiliation(s)
- JA Kabin
- Department of Chemical Engineering, North Carolina State University, Raleigh, North Carolina, 27695-7905
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428
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Sirimanne SR, Patterson DG, Ma L, Justice JB. Application of cloud-point extraction-reversed-phase high-performance liquid chromatography. A preliminary study of the extraction and quantification of vitamins A and E in human serum and whole blood. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 716:129-37. [PMID: 9824225 DOI: 10.1016/s0378-4347(98)00287-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Methods available for quantification of vitamins A and E in serum or blood requires preconcentration and clean-up by liquid-liquid extraction, evaporation of the extract, and reconstitution of the extract in a solvent of choice before analysis. This process not only involves the use of toxic organic solvents but also requires a long sample preparation time. The lipids and other non-polar coextractants often require additional steps for sample clean-up and evaporation, which may cause sample losses. The use of cloud-point extraction eliminates most of these sample clean-up problems. We recently demonstrated that cloud-point extraction (CPE) can be used for extraction and quantification of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated dibenzo-p-dioxins (PCDDs) from human serum. We now demonstrate how CPE can be used with human serum and blood, at volumes as low as 50 microl, and report a methodology for extracting and quantifying two clinically important vitamins, (A and E) from human serum and blood. Vitamins A and E were extracted from human serum and blood by using Genapol X-80 as the cloud-point extractant under salting out conditions. Serum and blood samples were diluted in organic-free water to get sufficiently large sample volumes for CPE. The surfactant-rich phases were separated by centrifugation, and the samples were analyzed by HPLC-UV after deleterious coextractants were removed by precipitating them with acetonitrile. The recoveries of spiked vitamins A and E were found to be 85.6+/-0.4% and 82.6+/-5.2%, respectively. The average concentration of vitamins A and E in a serum pool after correction for recoveries were found to be 43.4+/-1.8 microg/dl (1.5+/-0.1 micromol/l) and 564.3+/-65.3 microg/dl (13.1+/-1.5 micromol/l), respectively. Vitamin A and E concentrations in whole blood were found to be 26.3+/-0.4 microg/dl (0.92+/-0.01 micromol/l) and 457.5+/-15.6 microg/dl (10.6+/-0.4 micromol/l), respectively. These values are comparable with those obtained by the reference method used at the Centers for Disease Control and Prevention. The success of the preliminary study will lead to a comprehensive validation of this method for vitamins A and E in serum and blood.
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Affiliation(s)
- S R Sirimanne
- Division of Environmental Health Laboratory Sciences, National Centers for Environmental Health, Centers for Disease Control and Prevention, Public Health Service, US Department of Health and Human Services, Atlanta, GA 30341-3724, USA
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429
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Tagashira S, Murakami Y, Yano M, Sasaki Y. Extraction and Stripping of Copper(I) as a Neocuproine Complex in a Surfactant System and Determination of Copper in Steel. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1998. [DOI: 10.1246/bcsj.71.2137] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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430
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Tong A, Wu Y, Tan S, Li L, Akama Y, Tanaka S. Aqueous two-phase system of cationic and anionic surfactant mixture and its application to the extraction of porphyrins and metalloporphyrins. Anal Chim Acta 1998. [DOI: 10.1016/s0003-2670(98)00209-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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431
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Sabry SM. Determination of flufenamic and mefenamic acids in pharmaceutical preparations using organized media. Anal Chim Acta 1998. [DOI: 10.1016/s0003-2670(98)00172-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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432
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Liu CL, Kamei DT, King JA, Wang DI, Blankschtein D. Separation of proteins and viruses using two-phase aqueous micellar systems. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 711:127-38. [PMID: 9699982 DOI: 10.1016/s0378-4347(98)00013-9] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We discuss the utilization of a novel two-phase aqueous nonionic micellar system for the purification and concentration of biomolecules, such as proteins and viruses, by liquid-liquid extraction. The nonionic surfactant n-decyl tetra(ethylene oxide), C10E4, phase separates in water into two coexisting aqueous micellar phases by increasing temperature. The mild interactions of the C10E4 nonionic surfactant with biomolecules, combined with the high water content of the two coexisting micellar phases, suggest the potential utility of two-phase aqueous C10E4 micellar systems for the purification and concentration of biomolecules. In this paper, we review our recent experimental and theoretical studies involving the partitioning of several water-soluble proteins, including cytochrome c. soybean trypsin inhibitor, ovalbumin, bovine serum albumin, and catalase, in the two-phase aqueous C10E4 micellar system. In addition, we present results of our preliminary experimental investigation on the partitioning of bacteriophages, including phiX174, P22, and T4.
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Affiliation(s)
- C L Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge 02139, USA
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433
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Mishra A, Behera P, Behera R, Mishra B, Behera G. Interaction of N-alkyl styryl pyridinium dyes with TX-100 in aqueous medium: Role of the alkyl chain during solubilisation. J Photochem Photobiol A Chem 1998. [DOI: 10.1016/s1010-6030(98)00268-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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434
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Tani H, Ooura T, Kamidate T, Kamataki T, Watanabe H. Separation of microsomal cytochrome b5 via phase separation in a mixed solution of Triton X-114 and charged dextran. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 708:294-8. [PMID: 9653976 DOI: 10.1016/s0378-4347(98)00002-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The successful introduction of a charged dextran into the Triton X-114 phase separation system for the selective extraction of cytochrome b5 (cyt. b5) in liver microsomes is described. In the absence of charged dextran, 55% of total microsomal proteins and 84% of cyt. b5 were extracted into the surfactant-rich phase. In the presence of anionic dextran sulfate, the extractability of total microsomal proteins was greatly reduced while that of cyt. b5 was increased. After triplicate extraction, cyt. b5 was purified more than 10-fold from microsomes with a recovery of 91% in the surfactant-rich phase. In view of its operational simplicity, this method provides a good means for the partial purification of cyt. b5 prior to chromatographic separations.
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Affiliation(s)
- H Tani
- Laboratory of Bioanalytical Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Japan
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435
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Affiliation(s)
- Hirofumi TANI
- Laboratory of Bioanalytical Chemistry, Graduate School of Engineering, Hokkaido University
| | - Tamio KAMIDATE
- Laboratory of Bioanalytical Chemistry, Graduate School of Engineering, Hokkaido University
| | - Hiroto WATANABE
- Laboratory of Bioanalytical Chemistry, Graduate School of Engineering, Hokkaido University
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436
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Lee CK, Su WD. Separation of Phenylacetic Acid from 6-Aminopenicillanic Acid via Cloud-Point Extraction with N-Decyltetra(ethylene Oxide) Nonionic Surfactant. SEP SCI TECHNOL 1998. [DOI: 10.1080/01496399808545004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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437
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TAGASHIRA S, MURAKAMI Y, OTOBE S, SASAKI Y. Stripping of Zinc(II) as EDTA Complex from the Surfactant Phase for the Determination of Zincin Sugar by Atomic Absorption Spectrometry. ANAL SCI 1998. [DOI: 10.2116/analsci.14.849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Shoji TAGASHIRA
- Department of Chemistry, Faculty of Science, Yamaguchi University
| | - Yoshiko MURAKAMI
- Department of Chemistry, Faculty of Science, Yamaguchi University
| | - Shouji OTOBE
- Department of Chemistry, Faculty of Science, Yamaguchi University
| | - Yoshiaki SASAKI
- Department of Chemistry, Faculty of Science, Yamaguchi University
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438
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Eiguren Fernández A, Sosa Ferrera Z, Santana Rodrı́guez J. Determination of polychlorinated biphenyls by liquid chromatography following cloud-point extraction. Anal Chim Acta 1998. [DOI: 10.1016/s0003-2670(97)00618-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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439
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Schwarz A, Terstappen GC, Futerman AH. Isolation of gangliosides by cloud-point extraction with a nonionic detergent. Anal Biochem 1997; 254:221-5. [PMID: 9417780 DOI: 10.1006/abio.1997.2419] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A rapid, simple, and efficient chloroform/methanol-free method of isolating gangliosides is described. The nonionic polyoxyethylene detergent, hexaethyleneglycol mono-n-tetradecyl ether (C14EO6), forms clear micellar solutions in water, but two-phase separation can be achieved by centrifugation in the presence of ammonium sulfate at room temperature. A mixture of pure gangliosides, metabolically labeled gangliosides obtained from cultured hippocampal neurons, and gangliosides from rat cerebellar tissue were quantitatively recovered in the detergent-rich upper (coacervate) phase, with a partition coefficient K > 60. Gangliosides were subsequently separated from the detergent using an Iatrobead column prior to analysis by thin-layer chromatography. The procedure described here is as efficient as other methods of ganglioside extraction, such as that using chloroform/methanol/water/pyridine, but is less time-consuming inasmuch as extraction, purification, and TLC analysis can be completed within 1 day.
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Affiliation(s)
- A Schwarz
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
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440
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Tani H, Saitoh T, Kamidate T, Kamataki T, Watanabe H. Polymer-induced phase separation in aqueous micellar solutions of octyl-β-D-thioglucoside for extraction of membrane proteins. Biotechnol Bioeng 1997; 56:311-8. [DOI: 10.1002/(sici)1097-0290(19971105)56:3<311::aid-bit9>3.0.co;2-m] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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441
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Radwan N, King AD. Solubilization of Gases by Polyethoxylated Octyl Phenols. J Colloid Interface Sci 1997; 194:120-6. [PMID: 9367591 DOI: 10.1006/jcis.1997.5072] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Measurements have been made to determine the solubilities of a number of gases in aqueous solutions of commercially available polyethoxylated octyl phenols at temperatures ranging from 25°C to 45°C (298-318 K). The solubilities determined for each gas increase linearly with surfactant concentration. The intramicellar gas solubilities derived from these data are found to be relatively insensitive to temperature and sodium chloride in the external aqueous phase. When analyzed in terms of surfactant composition, the intramicellar gas solubilities are found to depend solely on the octyl phenol content of each surfactant. This suggests that the ethylene oxide chains of the micellized surfactant molecules do not contribute directly to the solubilization process, even under conditions near the cloud point. Copyright 1997 Academic Press. Copyright 1997Academic Press
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Affiliation(s)
- N Radwan
- Department of Chemistry, University of Georgia, Athens, Georgia, 30602
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442
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443
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444
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Umebayashi Y, Shin M, Ishiguro S. Thiocyanato and Iodo Complexation of Cadmium(II) Ions in Micellar Solutions of a Nonionic Surfactant Triton X-100. J Colloid Interface Sci 1997; 191:391-7. [PMID: 9268522 DOI: 10.1006/jcis.1997.4937] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Complexation of the cadmium(II) ion with thiocyanate and iodide ions have been studied by precise titration calorimetry in micellar solutions of a nonionic surfactant Triton X-100 containing 0.4 mol dm-3 NaClO4 as a constant ionic medium at 298 K. With regard to the Cd(II)-SCN- system, the formation of [Cd(NCS)]+ and [Cd(NCS)(SCN)] in aqueous solution and [Cd(NCN)2(SCN)]- in micelles was established, though the complexation in micelles is not extensive. With the Cd(II)-I- system, the formation of [CdI]+, [CdI3]-, and [CdI4]2- was established in aqueous solution together with the formation of [CdI2], [CdI3]-, and [CdI4]2- in micelles. It is revealed that the complexation in micelles is accompanied by relatively large and negative enthalpies, which is ascribed to the enthalpies of transfer of [CdI3]- and [CdI4]2- from aqueous solution to micelles. This suggests that a hydrophobic complex with no capacity to form strong hydrogen bonds in water is favored in micelles.
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Affiliation(s)
- Y Umebayashi
- Faculty of Science, Kyushu University, Hakozaki, Higashi-ku, Fukuoka, 812-81, Japan
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445
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446
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Silva M, Fernandez L, Olsina RA, Stacchiola D. Cloud point extraction, preconcentration and spectrophotometric determination of erbium(III)-2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminophenol. Anal Chim Acta 1997. [DOI: 10.1016/s0003-2670(96)00603-4] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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447
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Tagashira S, Murakami Y, Nishiyama M, Harada N, Sasaki Y. Surfactant Extraction and Determination of Ruthenium(III) as a Thiocyanato Complex. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1996. [DOI: 10.1246/bcsj.69.3195] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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448
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Determination of the fungicides folpet, captan and captafol by cloud-point preconcentration and high-performance liquid chromatography with electrochemical detection. J Chromatogr A 1996. [DOI: 10.1016/s0021-9673(96)00391-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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449
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Use of cloud point extraction methodology for the determination of PAHs priority pollutants in water samples by high-performance liquid chromatography with fluorescence detection and wavelength programming. Anal Chim Acta 1996. [DOI: 10.1016/0003-2670(96)00176-6] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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450
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Spectrophotometric study of thiocyanato complexation of cobalt(II) and nickel(II) ions in micellar solutions of a nonionic surfactant triton X-100. J SOLUTION CHEM 1996. [DOI: 10.1007/bf00973781] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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