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Pigliacelli C, Belton P, Wilde P, Qi S. Probing the molecular interactions between pharmaceutical polymeric carriers and bile salts in simulated gastrointestinal fluids using NMR spectroscopy. J Colloid Interface Sci 2019; 551:147-154. [PMID: 31075629 DOI: 10.1016/j.jcis.2019.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/29/2019] [Accepted: 05/01/2019] [Indexed: 02/04/2023]
Abstract
The number of poorly soluble new drugs is increasing and one of the effective ways to deliver such pharmaceutically active molecules is using hydrophilic polymers to form a solid dispersion. Bile salts play an important role in the solubilisation of poorly soluble compounds in the gastrointestinal tract (gut) prior to absorption. When a poorly water-soluble drug is delivered using a hydrophilic polymer based solid dispersion oral formulation, it is still unclear whether there are any polymer-bile salt interactions, which may influence the drug dissolution and solubilisation. This study, using two widely used hydrophilic model polymers, Hydroxypropyl methylcellulose (HPMC) and polyvynilpirrolidone (PVP), and sodium taurocholate (NaTC) as the model bile salt, aims to investigate the interactions between the polymers and bile salts in simulated fed state (FeSSIF) and fasted state (FaSSIF) gut fluids. The nature of the interactions was characterised using a range of NMR techniques. The results revealed that the aggregation behaviour of NaTC in FaSSIF and FeSSIF is much more complex than in water. The addition of hydrophilic polymers led to the occurrences of NaTC-HPMC and NaTC-PVP aggregation. For both systems, pH and ionic strength strongly influenced the aggregation behavior, while the ion type played a less significant role. The outcome of this study enriched the understanding of the aggregation behaviour of bile salts and typical hydrophilic pharmaceutical polymers in bio-relevant media. Due to the high surface-activity of the bile salts and their ability to interact with polymers, such aggregation behaviour is expected to play a role in drug solubilisation in the gut when the drug is delivered by hydrophilic polymer based dispersions.
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Affiliation(s)
| | - Peter Belton
- School of Chemistry, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK
| | - Peter Wilde
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UA, UK
| | - Sheng Qi
- School of Pharmacy, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK.
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2
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Štukelj J, Svanbäck S, Kristl J, Strachan CJ, Yliruusi J. Image-Based Investigation: Biorelevant Solubility of α and γ Indomethacin. Anal Chem 2019; 91:3997-4003. [PMID: 30784269 PMCID: PMC6727188 DOI: 10.1021/acs.analchem.8b05290] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Solubility is a physicochemical property highly dependent on the solid-state form of a compound. Thus, alteration of a compound's solid-state form can be undertaken to enhance the solubility of poorly soluble drug compounds. In the Biopharmaceutics Classification System (BCS), drugs are classified on the basis of their aqueous solubility and permeability. However, aqueous solubility does not always correlate best with in vivo solubility and consequently bioavailability. Therefore, the use of biorelevant media is a more suitable approach for mimicking in vivo conditions. Here, assessed with a novel image-based single-particle-analysis (SPA) method, we report a constant ratio of solubility increase of 3.3 ± 0.5 between the α and γ solid-state forms of indomethacin in biorelevant media. The ratio was independent of pH, ionic strength, and surfactant concentration, which all change as the drug passes through the gastrointestinal tract. On the basis of the solubility ratio, a free-energy difference between the two polymorphic forms of 2.9 kJ/mol was estimated. Lastly, the use of the SPA approach to assess solubility has proven to be simple, fast, and both solvent- and sample-sparing, making it an attractive tool for drug development.
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Affiliation(s)
- Jernej Štukelj
- Division of Pharmaceutical Chemistry and Technology , University of Helsinki , Viikinkaari 5E , 00790 Helsinki , Finland.,The Solubility Company , Viikinkaari 6 , 00790 Helsinki , Finland
| | - Sami Svanbäck
- Division of Pharmaceutical Chemistry and Technology , University of Helsinki , Viikinkaari 5E , 00790 Helsinki , Finland.,The Solubility Company , Viikinkaari 6 , 00790 Helsinki , Finland
| | - Julijana Kristl
- University of Ljubljana , Faculty of Pharmacy , Aškerčeva 7 , 1000 Ljubljana , Slovenia
| | - Clare J Strachan
- Division of Pharmaceutical Chemistry and Technology , University of Helsinki , Viikinkaari 5E , 00790 Helsinki , Finland
| | - Jouko Yliruusi
- Division of Pharmaceutical Chemistry and Technology , University of Helsinki , Viikinkaari 5E , 00790 Helsinki , Finland
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3
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Molecular interactions governing the incorporation of cholecalciferol and retinyl-palmitate in mixed taurocholate-lipid micelles. Food Chem 2018; 250:221-229. [DOI: 10.1016/j.foodchem.2018.01.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 12/12/2017] [Accepted: 01/07/2018] [Indexed: 01/12/2023]
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4
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Neubrand MW, Carey MC, Laue TM. Influence of Phosphatidylcholine and Calcium on Self-Association and Bile Salt Mixed Micellar Binding of the Natural Bile Pigment, Bilirubin Ditaurate. Biochemistry 2015; 54:6783-95. [DOI: 10.1021/acs.biochem.5b00874] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Michael W. Neubrand
- Department of Medicine, Harvard
Medical School, and Division of Gastroenterology, Brigham and Women’s Hospital and Harvard Digestive Disease Center, Boston, Massachusetts 02115, United States
| | - Martin C. Carey
- Department of Medicine, Harvard
Medical School, and Division of Gastroenterology, Brigham and Women’s Hospital and Harvard Digestive Disease Center, Boston, Massachusetts 02115, United States
| | - Thomas M. Laue
- Department of Biochemistry, University of New Hampshire, Durham, New Hampshire 03824, United States
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5
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Neubrand MW, Carey MC, Laue TM. Self-Assembly of Aqueous Bilirubin Ditaurate, a Natural Conjugated Bile Pigment, to Contraposing Enantiomeric Dimers and M(−) and P(+) Tetramers and Their Selective Hydrophilic Disaggregation by Monomers and Micelles of Bile Salts. Biochemistry 2015; 54:1542-57. [DOI: 10.1021/bi501251v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Michael W. Neubrand
- Department of Medicine, Harvard Medical
School, and Division of Gastroenterology, Brigham and Women’s
Hospital and Harvard Digestive Diseases Center, Boston, Massachusetts 02115, United States
| | - Martin C. Carey
- Department of Medicine, Harvard Medical
School, and Division of Gastroenterology, Brigham and Women’s
Hospital and Harvard Digestive Diseases Center, Boston, Massachusetts 02115, United States
| | - Thomas M. Laue
- Department of Biochemistry, University of New Hampshire, Durham, New Hampshire 03824, United States
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6
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Haustein M, Schiller P, Wahab M, Mögel HJ. Computer Simulations of the Formation of Bile Salt Micelles and Bile Salt/DPPC Mixed Micelles in Aqueous Solutions. J SOLUTION CHEM 2014. [DOI: 10.1007/s10953-014-0239-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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Diffusion Properties of the Ternary System Human Serum Albumin–Sodium Cholate–Water. J SOLUTION CHEM 2014. [DOI: 10.1007/s10953-014-0179-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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8
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Mangiapia G, Paduano L, Ortona O, Sartorio R, D'Errico G. Analysis of main- and cross-term diffusion coefficients in bile salt mixtures. J Phys Chem B 2013; 117:741-9. [PMID: 23276326 DOI: 10.1021/jp309945f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mutual diffusion coefficients have been measured for several average compositions of the system sodium cholate-sodium deoxycholate-water at 25 °C. The experiments have been grouped in different sets having constant concentration of one component and variable concentration of the other one. Following this approach, it has been found that the trends of the main- and cross-term diffusion coefficients can be interpreted on the basis of the diffusion and equilibrium results of similar experiments performed on the two binary systems sodium cholate-water and sodium deoxycholate-water. Implications of the presented results in the transport of lipids operated by bile salt aggregates are mentioned. The method proposed in this work, able to connect the diffusivities of an n-component system to those of the related n-1 subsystems, can be extended to obtain qualitative prediction on the diffusion coefficient trends for mixtures of other surfactants, of both industrial and biological interest.
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Affiliation(s)
- Gaetano Mangiapia
- Department of Chemical Sciences, University of Naples Federico II and CSGI Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, Complesso di Monte Sant'Angelo, Via Cintia, 80126 Naples, Italy
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9
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Pace TCS, Souza Júnior SP, Zhang HT, Bohne C. Effect of terbium(iii) on the binding of aromatic guests with sodium taurocholate aggregates. Photochem Photobiol Sci 2011; 10:1568-77. [DOI: 10.1039/c1pp05130j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Mangiapia G, D'Errico G, Capuano F, Ortona O, Heenan RK, Paduano L, Sartorio R. On the interpretation of transport properties of sodium cholate and sodium deoxycholate in binary and ternary aqueous mixtures. Phys Chem Chem Phys 2011; 13:15906-17. [DOI: 10.1039/c1cp20922a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Fuentealba D, Thurber K, Bovero E, Pace TCS, Bohne C. Effect of sodium chloride on the binding of polyaromatic hydrocarbon guests with sodium cholate aggregates. Photochem Photobiol Sci 2011; 10:1420-30. [DOI: 10.1039/c1pp05058c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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13
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Li R, Santos CS, Norsten TB, Morimitsu K, Bohne C. Aqueous solubilization of photochromic compounds by bile salt aggregates. Chem Commun (Camb) 2010; 46:1941-3. [DOI: 10.1039/b926351a] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bile salt aggregates in water readily solubilize aqueous insoluble photochromic compounds.
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Affiliation(s)
- Rui Li
- Department of Chemistry
- University of Victoria
- Victoria
- Canada
| | | | | | | | - Cornelia Bohne
- Department of Chemistry
- University of Victoria
- Victoria
- Canada
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14
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Li R, Carpentier E, Newell ED, Olague LM, Heafey E, Yihwa C, Bohne C. Effect of the structure of bile salt aggregates on the binding of aromatic guests and the accessibility of anions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:13800-13808. [PMID: 19606836 DOI: 10.1021/la901826y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The binding of naphthalene (Np), 1-ethylnaphthalene (EtNp), acenaphthene (AcN), and 1-naphthyl-1-ethanol (NpOH) as guests to the aggregates of sodium cholate (NaCh), taurocholate (NaTC), deoxycholate (NaDC), and deoxytaurocholate (NaTDC) was studied with the objective of determining how the structure of the bile salts affects the binding dynamics of guests and quenchers with the bile salt aggregates. Time-resolved and steady-state fluorescence experiments were used to determine the binding efficiency of the guests with the aggregates and were also employed to investigate the quenching of the singlet excited state of the guests by iodide anions. Quenching studies of the triplet excited states using laser flash photolysis were employed to determine the accessibility to the aggregate of nitrite anions, used as quenchers, and the dissociation rate constants of the guests from the bile salt aggregates. The binding efficiency of the guests to NaDC and NaTDC is higher than for NaCh and NaTC, and the protection efficiency is also higher for NaDC and NaTDC, in line with the larger aggregates formed for the latter bile salts. The formation of aggregates is in part driven by the structure of the guest, where an increased protection efficiency and residence time can be achieved by the introduction of short alkyl substituents (AcN or EtNp vs Np). NpOH was shown to be located in a very different environment in all four bile salts when compared to AcN, EtNp, and Np, suggesting that hydrogen bonding plays an important role in the formation of the aggregate around NpOH.
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Affiliation(s)
- Rui Li
- Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia V8W 3 V6, Canada
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15
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Alvarez Alcalde M, Jover A, Meijide F, Galantini L, Viorel Pavel N, Antelo A, Vázquez Tato J. Aggregation behavior of tetracarboxylic surfactants derived from cholic and deoxycholic acids and ethylenediaminetetraacetic acid. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:9037-9044. [PMID: 19719219 DOI: 10.1021/la9007813] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The reaction of 3beta-aminoderivatives of cholic and deoxycholic acids (steroid residues) with dimethyl ester of ethylenediaminetetraacetic acid (bridge) leads to the formation of dimers carrying four carboxylic organic functions, two of them located on the side chain of each steroid residue and the other two on the bridge. As tetrasodium salts, these new compounds behave as surfactants and have been characterized by surface tension, fluorescence intensity of pyrene (as a probe), and static and dynamic light scattering measurements. Thermodynamic parameters for micellization were obtained from the dependence of the critical micelle concentration (cmc) with temperature. For both surfactants, the fraction of bound counterions is close to 0.5. The aggregation behavior is similar to one of their bile salt residues [i.e., sodium cholate (NaC) and sodium deoxycholate (NaDC)] and can be summarized as follows: (i) molecular areas at the interface for the new surfactants are fairly close to twice the value for a single molecule in a monolayer of natural bile salts; (ii) the environment where pyrene is solubilized is very apolar, as in natural bile salt aggregates; (iii) Gibbs free energies (per steroid residue) for micellization are not far from published values for NaC and NaDC, and the differences can be understood on the basis of less hydrophobicity of the new surfactants due to the charges in the bridge; and (iv) as for NaC and NaDC, aggregates have rather low aggregation numbers (which depend on the amount of added inert salt, NaCl). A structure based on the disklike model accepted for small bile salt aggregates is proposed.
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Affiliation(s)
- Mercedes Alvarez Alcalde
- Departamento de Química Física, Facultad de Ciencias, Universidad de Santiago de Compostela, Avda. Alfonso X El Sabio s/n, 27002 Lugo, Spain
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16
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The CMC-like behaviour of bile salts as probed by photoexcited Rose Bengal. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.02.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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17
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Zhang HM, Wang Y, Jin WJ. Study on the kinetic properties of phosphor in deoxycholate aggregates by phosphorescent quenching methodology. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 88:36-42. [PMID: 17570675 DOI: 10.1016/j.jphotobiol.2007.04.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 02/17/2007] [Accepted: 04/30/2007] [Indexed: 11/20/2022]
Abstract
Owing to the unique molecular structure and aggregate behaviors in aqueous solution, dihydroxy bile salts can provide phosphorescent probe with a special microenvironment in which the room temperature phosphorescence of probe can be detected in the presence of dissolved oxygen. It, however, is not very clear how the bile salts work in inducing this kind of oxygen-independent phosphorescence. The present work tries to offer with possible more insights by investigating the particular kinetic behaviors of 3-bromoquinoline (3-BrQ) as probe in sodium deoxycholate (NaDC) aggregate based on phosphorescent quenching methodology. The critical aggregate concentration of NaDC is estimated as about 0.5mM based on the enhancement of probe phosphorescence. As the functions of quencher Cu(2+) and NO(2)(-), the rate constants of various photophysical processes for 3-BrQ are obtained in NaDC solution and full aqueous solution, respectively. In NaDC solution, the quenching rate constant k(cu2+) equals to 1.77x10(7)M(-1)s(-1) k(no-2)(mq) 1.62x10(6)M(-1)s(-1). The exit rate k(-) and entrance rate k(+) are determined to be 16-46s(-1) and 10(6)M(-1)s(-1) levels, respectively. The quenching rate constant k(o2)(q) of dissolved oxygen is estimated as 4.15x10(4)M(-1)s(-1) in air-saturated NaDC solution at 1atm.
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Affiliation(s)
- Hong-Mei Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China
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18
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Yihwa C, Bohne C. Effect of Solvent Polarity and Viscosity on the Guest Binding Dynamics with Bile Salt Aggregates†. Photochem Photobiol 2007; 83:494-502. [PMID: 17115797 DOI: 10.1562/2006-09-17-ra-1043] [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: 11/19/2022]
Abstract
Bile salts form supramolecular aggregates with two binding sites with different properties. The guest binding dynamics to the aggregates and guest protection from species in the aqueous phase were investigated using fluorescence and laser flash photolysis experiments. Sodium cholate, deoxycholate and taurodeoxycholate were used as bile salts and acetonitrile or ethylene glycol were added as co-solvents to water in order to alter the binding properties of 1-ethylnaphthalene and 1-naphthyl-1-ethanol with the aggregates. The binding dynamics are faster and protection efficiencies are lower for guests bound to cholate and in the presence of either co-solvent.
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Affiliation(s)
- Chang Yihwa
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
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19
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Vinceković M, Jurašin D, Tomašić V, Bujan M, Filipović‐Vinceković N. Interactions in Aqueous Mixtures of Alkylammonium Chlorides and Sodium Cholate. J DISPER SCI TECHNOL 2006. [DOI: 10.1080/01932690600858905] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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20
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Warren DB, Chalmers DK, Hutchison K, Dang W, Pouton CW. Molecular dynamics simulations of spontaneous bile salt aggregation. Colloids Surf A Physicochem Eng Asp 2006. [DOI: 10.1016/j.colsurfa.2006.02.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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21
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Waissbluth OL, Morales MC, Bohne C. Influence of Planarity and Size on Guest Binding with Sodium Cholate Aggregates. Photochem Photobiol 2006; 82:1030-8. [PMID: 16555923 DOI: 10.1562/2006-02-14-ra-803] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bile salt aggregates are supramolecular structures with two types of binding sites, called primary and secondary sites. The objective of this work was to explore how the nonplanarity and size of guests (biphenyl [BP], 1-1'-binaphthyl [BNP] and dibenz[b,f]oxepin [DBX]) affected their binding affinity and dynamics to sodium cholate (NaC) aggregates. Fluorescence and laser-flash photolysis experiments were performed to obtain information on the binding environment for the guests, the accessibility of quenchers to guests in the aggregate and the dissociation rate constants of the guests from the aggregates. All guests were bound to the more hydrophobic primary aggregate, showing that this site can accommodate nonplanar molecules. However, the structure of the guest affects the structure of the primary aggregates, leading to changes in the accessibility of anions to aggregate-bound guests and to changes for the guest dissociation rate constants from the aggregates.
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22
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Rinco O, Nolet MC, Ovans R, Bohne C. Probing the binding dynamics to sodium cholate aggregates using naphthalene derivatives as guests. Photochem Photobiol Sci 2005; 2:1140-51. [PMID: 14690227 DOI: 10.1039/b308335g] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The binding dynamics with bile salt aggregates for a series of naphthalene derivatives of different polarities was studied using fluorescence and laser flash photolysis. Fluorescence was employed to determine the nature of the binding site for each guest and the accessibility of the bound guest to quenchers. Laser flash photolysis was employed to study the mobility of the triplet states of the naphthalenes between the sodium cholate aggregates and the aqueous phase. Primary aggregates, which provide an environment protected from quenchers in the aqueous phase, bind 1- and 2-ethylnaphthalene as guests. The complexation dynamics with this type of aggregate is slow. 1- and 2-Naphthyl-1-ethanol, and 1- and 2-acetonaphthone bind to the secondary aggregates, which provide moderate protection from quenching and faster binding dynamics. The addition of salts lowered the cholate concentration at which primary aggregates were formed, but did not influence the formation of secondary aggregates.
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Affiliation(s)
- Olga Rinco
- Department of Chemistry, University of Victoria, PO Box 3065, Victoria, BC, Canada V8W 3V6
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24
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Funasaki N, Fukuba M, Kitagawa T, Nomura M, Ishikawa S, Hirota S, Neya S. Two-Dimensional NMR Study on the Structures of Micelles of Sodium Taurocholate. J Phys Chem B 2003. [DOI: 10.1021/jp030899h] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Noriaki Funasaki
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Makoto Fukuba
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Tomohiro Kitagawa
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Masao Nomura
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Seiji Ishikawa
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Shun Hirota
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Saburo Neya
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
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25
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Sugioka H, Matsuoka K, Moroi Y. Temperature effect on formation of sodium cholate micelles. J Colloid Interface Sci 2003; 259:156-62. [PMID: 12651144 DOI: 10.1016/s0021-9797(02)00191-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The micellization of sodium cholate (NaC) at 293.2, 298.2, 303.2, 308.2, and 313.2 K by cholate anion concentration was studied over the pH range from 6.0 to 7.2. Using a stepwise association model of cholate anions without bound sodium counterions, the aggregation number (nmacr;) of the cholate micelles was evaluated and found to increase with the total concentration, indicating that the stepwise association model is applicable. The nmacr; values go up and down with increasing temperature; 17 at 298.2 and 12 at 313.2 K and at 60 mM of the sodium cholate. The fluorescence of pyrene was measured in sodium cholate solution to determine the critical micelle concentration (CMC), indicating a narrow concentration range for CMC. A sodium-ion-specific electrode was used to determine a relatively low degree of counterion binding to micelles, supporting the validity of the present association model of cholate anions. The aggregation numbers evaluated at a constant ionic strength of 0.15 and at lower but variable ionic strengths were similar except for higher cholate concentrations.
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Affiliation(s)
- Hiromi Sugioka
- Graduate School of Sciences, Kyushu University-Ropponmatsu, Chuo-ku, Fukuoka 810-8560, Japan
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26
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Ueno M, Takamura Y, Nagadome S, Sugihara G, Takahashi K. NMR study of bile salts' molecules in binary mixed micelles of bile salt and a non-ionic surfactant. Colloids Surf B Biointerfaces 2000. [DOI: 10.1016/s0927-7765(99)00163-0] [Citation(s) in RCA: 11] [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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27
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Avranas A, Tasopoulos V. Aqueous Solutions of Sodium Deoxycholate and Hydroxypropylmethylcellulose: Dynamic Surface Tension Measurements. J Colloid Interface Sci 2000; 221:223-229. [PMID: 10631023 DOI: 10.1006/jcis.1999.6574] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Interfacial tension changes and interaction between sodium deoxycholate (DOC) and a nonionic polymer hydroxypropylmethylcellulose (HPMC) were studied by the Wilhelmy plate method. The concentration of HPMC was fixed at 8x10(-5), 2x10(-4), and 1x10(-3)% (w/v) while DOC ranged form 0 to 8x10(-2) M, i.e., concentrations below and above the critical micellar concentration (cmc) for DOC. Emphasis was placed on the highly diluted solutions of the polymer in order to lessen possible contributions of the effects of the bulk phase on the observed surface behavior. The dynamics of the surface tension was investigated in the presence and absence of DOC. The kinetics of the interfacial tension changes were explained in terms of adsorption of the polymer molecules and conformational changes of already adsorbed molecules at the interface. The molecules above a critical DOC aggregation concentration (cac) formed clusters, which was evidenced by these surface tension measurements. A synergism in surface activity was observed below that cac. The cmc of DOC remained unchanged by the presence of HPMC. Copyright 2000 Academic Press.
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Affiliation(s)
- A Avranas
- Laboratory of Physical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, 54006, Greece
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Sugihara G, Hisatomi M. Enthalpy-Entropy Compensation Phenomenon Observed for Different Surfactants in Aqueous Solution. J Colloid Interface Sci 1999; 219:31-36. [PMID: 10527569 DOI: 10.1006/jcis.1999.6378] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Based on previously reported thermodynamic data such as changes of the Gibbs energy (DeltaG(m)( degrees )), the enthalpy (DeltaH(m)( degrees )), and the entropy (DeltaS(m)( degrees )) on micelle formation of more than 15 species of surfactants (including nonionic, anionic, and cationic surfactants), plots of DeltaH(m)( degrees ) vs DeltaS(m)( degrees ) (not of DeltaS(m)( degrees ) vs DeltaH(m)( degrees ), as is usually done) were made. For each surfactant, a linear relation having almost the same slope (1/307 K(-1)) within a small error (+/-2.3%) but a different intercept (varsigma) depending on the surfactant species was obtained, i.e., DeltaS(m)( degrees ) = (1/307)DeltaH(m)( degrees ) + varsigma, where 1/307 (K(-1)) means that the so-called compensation temperature (T(C)) is 307 K. Strictly speaking, T(C) ranges from 299 to 315 K, depending on the species. The intercept corresponds to the entropy change at a specific temperature giving DeltaH(m)( degrees ) = 0, at which the driving force of micelle formation comes only from the entropy term; this temperature is characteristic of the surfactant species. On the other hand, the compensation temperature has no significant meaning other than a mean temperature studied. Copyright 1999 Academic Press.
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Affiliation(s)
- G Sugihara
- Faculty of Science, Fukuoka University, Jonan-ku, Fukuoka, 814-0180, Japan
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29
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Funasaki N, Hada S, Neya S. Self-Association Patterns of Sodium Taurocholate and Taurodeoxycholate As Studied by Frontal Derivative Chromatography. J Phys Chem B 1998. [DOI: 10.1021/jp983202e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Noriaki Funasaki
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Sakae Hada
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Saburo Neya
- Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
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30
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Navas Dı́az A, Garcı́a Sánchez F, Garcı́a Pareja A. Cholic acid behavior in water and organic solvent: study of normal and inverted aggregates. Colloids Surf A Physicochem Eng Asp 1998. [DOI: 10.1016/s0927-7757(98)00370-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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31
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Sugioka H, Moroi Y. Micelle formation of sodium cholate and solubilization into the micelle. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1394:99-110. [PMID: 9767136 DOI: 10.1016/s0005-2760(98)00090-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The micellization of sodium cholate (NaC) was studied at 298.2 K by aqueous solubility at different pH values. Using a stepwise association model of cholate anions without the sodium counterion, the aggregation number (n) of the cholate micelle was evaluated and found to increase with the total concentration, indicating that the mass action model worked quite well. The n value at 60 mM was found equal to 16. The membrane potential measurement of sodium ion with a cation exchange membrane was made in order to confirm the low counterion binding to micelle. The solubilization of alkylbenzenes (benzene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, n-pentylbenzene, n-hexylbenzene) and polycyclic aromatic compounds (naphthalene, anthracene, pyrene) into the aqueous micellar solution of sodium cholate was carried out. Solubilizate concentrations at equilibrium were determined spectrophotometrically at 298.2 K. The first stepwise association constants (K1) between solubilizate monomer and vacant micelle were evaluated from the equilibrium concentrations and found to increase with increasing hydrophobicity of the solubilizate molecules. From the Gibbs energy change for solubilization at the different mean aggregation numbers and from molecular structure of the solubilizates, the function of sodium cholate micelle for solubilization was discussed and was compared with data from conventional aliphatic micelles.
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Affiliation(s)
- H Sugioka
- Department of Chemistry, Faculty of Science, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
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32
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Thermodynamic Analysis of the Adsorbed Film of Sodium Taurodeoxycholate Formed at the Aqueous Solution/Hexane Interface. J Colloid Interface Sci 1998. [DOI: 10.1006/jcis.1998.5529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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33
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Matubayasi N, Sugiyama S, Kanzaki M, Matuzawa A. Thermodynamic Studies of the Adsorbed Films and Micelles of Sodium Taurodeoxycholate. J Colloid Interface Sci 1997; 196:123-127. [PMID: 9792737 DOI: 10.1006/jcis.1997.5213] [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
Surface tension of aqueous solutions was measured for sodium taurodeoxycholate, as a typical example of the bile salt compounds, in the temperature range 20 to 35 degreesC at 2.5 degreesC intervals and concentration range 0 to 7 mmol kg-1. We examined thermodynamic quantities obtainable from the surface tension measurements according to the thermodynamic relations given by K. Motomura [J. Colloid Interface Sci. 64, 348 (1978)]. Sodium taurodeoxycholate was strongly adsorbed and formed the saturated adsorbed film at low concentrations. However, the gaseous/expanded phase transition does not take place in the film. The thermodynamic quantities associated with adsorption did not change as markedly at the critical micelle concentration as those observed for typical surfactants. It was suggested that molecular interactions between sodium taurodeoxycholate molecules in aqueous solutions and adsorbed films are too weak to induce critical changes in the thermodynamic quantities. Copyright 1997 Academic Press.
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Affiliation(s)
- N Matubayasi
- Faculty of Fisheries, Nagasaki University, 1-14 Bunkyou-machi, Nagasaki, 852, Japan
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34
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Liu CL. Cholesterol Binding to Simple Micelles in Aqueous Bile-Salt-Cholesterol Solutions. J Colloid Interface Sci 1997; 190:261-8. [PMID: 9241165 DOI: 10.1006/jcis.1997.4836] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The true thermodynamic activity (A T ) of cholesterol (Ch) in aqueous solutions containing taurocholate (TC)-Ch was determined by employing a direct assay of a 1 x 2-cm silicone polymer film with 0.025 cm thickness. Using the A T data, information on the nature of micellar species present in the TC-Ch system, and employing a binding-site model previously developed for tauroursodeoxycholate (TUDC)-Ch and taurochenodeoxycholate (TCDC)-Ch systems, it appeared that the Ch-binding affinity for simple bile-salt micelles corresponds precisely with the order of hydrophobicity, TUDC < TC < TCDC. Further, although simple TC micelles and simple TCDC micelles have similar binding capacities, the first Ch binding to a simple TC micelle may not significantly facilitate the second Ch binding, as occurs in simple TCDC micelles. For TUDC-Ch, TC-Ch, and TCDC-Ch systems, the concentration of bound simple micelles increased with increasing A T values, whereas the unbound simple micelle concentration decreased proportionally. These results provide insights into the possible influence of bile-salt species on Ch-binding to simple micelles in bile-salt-Ch solutions.
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Affiliation(s)
- CL Liu
- Institute of Biotechnology, National Dong-Hwa University, Shou-Feng, Hualien Hsien, Taiwan, Republic of China
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35
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Determination of critical micelle concentration of bile acid salts by micro-calorimetric titration. Mikrochim Acta 1997. [DOI: 10.1007/bf01243172] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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Hao L, Lu R, Leaist DG, Poulin PR. Aggregation number of aqueous sodium cholate micelles from mutual diffusion measurements. J SOLUTION CHEM 1997. [DOI: 10.1007/bf02767916] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Behaviors of sodium glycochenodeoxycholate and sodium glycoursodeoxycholate in binary mixed micelles of bile salt and nonionic surfactant. Colloids Surf B Biointerfaces 1996. [DOI: 10.1016/0927-7765(96)01304-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Navas Díaz A, García Pareja A, García Sánchez F. Normal-phase liquid chromatography of plant hormones using reversed cholic acid micelles as the mobile phase. Anal Chem 1996; 68:3029-32. [PMID: 8794933 DOI: 10.1021/ac951124a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
When several plant hormones with similar structures are present in a sample, conventional analytical methods are not sufficiently selective to effectively differentiate them. However, the excellent selectivity of micellar liquid chromatography allows similarly structured compounds to be easily differentiated. We used reversed cholic acid micelles dissolved in tetrahydrofuran as the mobile phase in normal-phase chromatography of seven plant hormones. Our results conformed closely to those predicted by the pseudophase micellar liquid chromatography theory. The chromatographic efficiencies were calculated from the peak width and the retention times, and we compared these values with those obtained by reversed-phase chromatography using sodium dodecyl sulfate mobile phase in water. To test the efficiency of this selective method for the analysis of plant tissues that may also contain contaminants, we applied it to homogeneous suspensions of spiked maize roots. Recoveries ranged from 91 to 110%, the relative standard deviations were between 0.46 and 10.03%, and the detection limits were between 0.08 and 0.80 micrograms g-1.
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Affiliation(s)
- A Navas Díaz
- Departamento de Química Analitica, Facultad de Ciencias, Universidad de Málaga, Spain
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Coello A, Meijide F, Núñez ER, Tato JV. Aggregation behavior of bile salts in aqueous solution. J Pharm Sci 1996; 85:9-15. [PMID: 8926591 DOI: 10.1021/js950326j] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Freezing point depression, delta T/k, and pNa are measured and analyzed for aqueous solutions of trihydroxy (NaTC) and dihydroxy (NaDC and NaTDC) bile salts. The results show the existence of break points in the plot of delta T/k vs molality at 0.018, 0.013, and 0.007 m, respectively, in good agreement with previous published critical micelle concentration values. Above the break point bile salts form aggregates with average aggregation numbers of 2.59 +/- 0.12 (NaTC), 5.82 +/- 0.04 (NaDC), and 5.42 +/- 0.47 (NaTDC). Fractions of bound counterions are also deduced, being close to 0.3 for the three bile salts studied. This indicates that only one counterion is bound for every three monomers in the aggregate. The different structural models published for the bile salt aggregates are discussed.
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Affiliation(s)
- A Coello
- Departamento de Química Física, Universidad de Santiago, Lugo, Spain
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40
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D'Alagni M, Galantini L, Giglio E, Gavuzzo E, Scaramuzza L. Micellar aggregates of sodium glycocholate and sodium taurocholate and their interaction complexes with bilirubin-IXα. Structural models and crystal structure. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/ft9949001523] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Solubilization of cholesterol in two binary mixed micelles of bile salt and nonionic surfactant. J AM OIL CHEM SOC 1994. [DOI: 10.1007/bf02541471] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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42
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Jain MK, Rogers J, Hendrickson HS, Berg OG. The chemical step is not rate-limiting during the hydrolysis by phospholipase A2 of mixed micelles of phospholipid and detergent. Biochemistry 1993; 32:8360-7. [PMID: 8347632 DOI: 10.1021/bi00083a040] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The effect of detergents on the overall catalytic turnover by secreted phospholipase A2 (PLA2) on codispersions of the substrate phospholipid is characterized. The overall rate of interfacial catalytic turnover depends on the effective substrate "concentration" (mole fraction) that the bound enzyme "sees" at the interface. Therefore, besides the intrinsic catalytic turnover rate determined by the Michaelis-Menten cycle in the interface [Berg et al. (1991) Biochemistry 30, 7283], two other interfacial processes significantly alter the overall effective rate of hydrolysis: first, the fraction of the total enzyme at the interface; second, the rate of replenishment of the substrate. At low mole fractions (< 0.3), bile salts promote the binding of pig pancreatic PLA2 to zwitterionic vesicles, and the rate of hydrolysis increases with the fraction of the enzyme in the interface. At higher (> 0.3) mole fractions of the detergent, the bilayer is disrupted, and the rate of hydrolysis decreases by more than a factor of 10. The detergent-dependent decrease in the rate of hydrolysis of the sn-2-oxyphospholipids is much larger than that of sn-2-thiophospholipid, and therefore the element effect (O/S ratio) decreases from about 10 in bilayers to less than 2 in mixed micelles. This loss of the element effect in mixed micelles shows that the chemical step is no longer rate-limiting during the hydrolysis of mixed micelles formed by the disruption of vesicles by the detergent. Such effects were observed with phospholipase A2 from several sources acting on substrates dispersed in a variety of detergents including bile salts, 2-deoxylysophosphatidylcholine, and Triton X-100.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M K Jain
- Department of Chemistry and Biochemistry, University of Delaware, Newark 19716
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Seret A, Van de Vorst A. Photophysical investigation of rose bengal in aqueous sodium taurocholate solutions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 1993. [DOI: 10.1016/1011-1344(93)85006-t] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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44
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Chiu YC, Yu KM. SIMULTANEOUS DETERMINATION OF MICELLAR DISSOCIATION CONCENTRATION AND CRITICAL MICELLAR CONCENTRATION OF BILE SALTS BY pH MEASUREMENTS. J DISPER SCI TECHNOL 1992. [DOI: 10.1080/01932699208943341] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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45
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Lamy-Freund MT, Schreier S, Peitzsch RM, Reed WF. Characterization and time dependence of amphotericin B: deoxycholate aggregation by quasielastic light scattering. J Pharm Sci 1991; 80:262-6. [PMID: 1646878 DOI: 10.1002/jps.2600800314] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Quasielastic light scattering measurements of amphotericin B (AB):deoxycholate (DOC) preparations provided information about particle size and aggregation as a function of concentration. The data allowed the time dependence of the aggregation to be followed and indicated that the initial rates of the change in average equivalent hydrodynamic diameter increased with decreasing concentration. The results extend the model proposed by Lamy-Freund and co-workers, which describes AB:DOC systems as consisting of AB:DOC mixed aggregates co-existing with pure DOC micelles. Although the AB:DOC aggregates are unstable at all concentrations studied, the rate of aggregation increases by three orders of magnitude as the concentration is reduced from 20 mM (DOC concentration) to the concentration region of DOC micellization. These results are in agreement with the different distribution of AB and DOC in the body of experimental animals, and may be of relevance for the understanding of the serious toxic effects of AB.
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46
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Properties of aqueous solutions for two binary mixed systems between two kinds of bile salts and nonionic surfactants. J AM OIL CHEM SOC 1990. [DOI: 10.1007/bf02541866] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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47
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48
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Lasic DD, Martin FJ, Neugebauer JM, Kratohvil JP. Phospholipid vesicles from mixed micelles of egg yolk lecithin and a zwitterionic detergent (CHAPS). J Colloid Interface Sci 1989. [DOI: 10.1016/s0021-9797(89)80071-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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49
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Zulauf M, Fürstenberger U, Grabo M, Jäggi P, Regenass M, Rosenbusch JP. Critical micellar concentrations of detergents. Methods Enzymol 1989; 172:528-38. [PMID: 2747541 DOI: 10.1016/s0076-6879(89)72032-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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50
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