101
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Richardson W, Dai S, Dyer M, Russo A, Neal M, Prindle T, Branca M, Sodhi C, Hackam D. Toll Like Receptor-4 Activation Links Enterocyte Autophagy with Apoptosis via the Stress Response Gene ATG 16 in the Pathogenesis of Necrotizing Enterocolitis. J Surg Res 2010. [DOI: 10.1016/j.jss.2009.11.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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102
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Dai S, Bancej C, Bienek A, Walsh P, Stewart P, Wielgosz A. Report summary - Tracking heart disease and stroke in Canada 2009. ACTA ACUST UNITED AC 2009. [DOI: 10.24095/hpcdp.29.4.06] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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103
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Richardson W, Gribar S, Branca M, Dai S, Afrazi A, Li J, Prindle T, Russo A, Sodhi C, Hackam D. 76. The NOD2 Agonist Muramyl-Di-Peptide (MDP) Reverses Toll Like Receptor-4 (TLR4)-Mediated Enterocyte Apoptosis Through Effects on the Novel Apoptosis Activating Protein SMAC-Diablo, and Attenuates the Severity of Intestinal Inflammation in Necrotizing Enterocolitis (NEC). J Surg Res 2009. [DOI: 10.1016/j.jss.2008.11.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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104
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Dai S, Marrack P, Kappler J. Crossreactive T cells spotlight the germline rules for TCR interactions with MHC molecules. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308089897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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105
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106
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Li W, Dai S, An J, Li P, Chen X, Xiong R, Liu P, Wang H, Zhao Y, Zhu M, Liu X, Zhu P, Chen JF, Zhou Y. Chronic but not acute treatment with caffeine attenuates traumatic brain injury in the mouse cortical impact model. Neuroscience 2007; 151:1198-207. [PMID: 18207647 DOI: 10.1016/j.neuroscience.2007.11.020] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 10/23/2007] [Accepted: 11/30/2007] [Indexed: 11/28/2022]
Abstract
Caffeine, the most consumed psychoactive drug and non-specific adenosine receptor antagonist, has recently been shown to exert a neuroprotective effect against brain injury in animal models of Parkinson's disease (PD) and stroke. However, the effects of caffeine on traumatic brain injury (TBI) are not known. In this study, we investigated the effects of acute and chronic caffeine treatment on brain injury in a cortical-impact model of TBI in mice. Following TBI, neurological deficits, cerebral edema, as well as inflammatory cell infiltration were all significantly attenuated in mice pretreated chronically (for 3 weeks) with caffeine in drinking water compared with the mice pretreated with saline. Furthermore, we found that chronic caffeine treatment attenuated glutamate release and inflammatory cytokine production, effects that were correlated with an upregulation of brain A1 receptor mRNA. By contrast, acute treatment with caffeine (i.p. injection, 30 min before TBI) was not effective in protecting against TBI-induced brain injury. These results suggest that chronic (but not acute) caffeine treatment attenuates brain injury, possibly by A1 receptor-mediated suppression of glutamate release and inhibition of excessive inflammatory cytokine production. These results highlight the potential benefit of chronic caffeine intake for preventing TBI and provide a rationale for the epidemiological investigation of the potential association between TBI and human caffeine intake.
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107
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Ravi P, Dai S, Tam KC. Synthesis and self-assembly of [60]fullerene containing sulfobetaine polymer in aqueous solution. J Phys Chem B 2007; 109:22791-8. [PMID: 16853969 DOI: 10.1021/jp053088h] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A well-defined poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA-b-C60) was synthesized using the atom transfer radical polymerization (ATRP) technique and betainized with 1,3-sulfobetaine to yield a Bet-PDMAEMA-b-C60. The solution properties were then studied by light transmittance, viscometric, 1H NMR laser light scattering, and transmission electron macroscopic techniques. It was found that Bet-PDMAEMA-b-C60 exhibits an upper critical solution temperature (USCT) similar to that observed for Bet-PDMAEMA in aqueous solution. However, the modification of Bet-PDMAEMA with a C60 molecule increases the UCST of Bet-PDMAEMA in solution, which is a function of the solution ionic strength. Addition of a small amount of salt increases the UCST, similar to polyelectrolyte systems, while the presence of an excess amount of salt leads to a decrease in the UCST, attributed to the antipolyelectrolyte effect of polyampholytes. In aqueous salt solution, Bet-PDMAEMA-b-C60 chains self-assemble into micelles that coexist with unimeric Bet-PDMAEMA-b-C60 chains. TEM studies revealed that the system agglomerates when the temperature exceeds the UCST.
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108
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Peyerl FW, Dai S, Murphy GA, Crawford F, White J, Marrack P, Kappler JW. Elucidation of some Bax conformational changes through crystallization of an antibody–peptide complex. Cell Death Differ 2006; 14:447-52. [PMID: 16946732 DOI: 10.1038/sj.cdd.4402025] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The Bcl-2 family member Bax plays a critical role in apoptosis. In healthy resting cells, Bax resides in the cytoplasm and loosely attached to the mitochondrial membrane. Apoptotic stimuli induce Bax activation, which is characterized by translocation and multimerization on the mitochondrial membrane surface resulting in exposure of an amino terminal epitope recognized by the monoclonal antibody 6A7. To understand the structural changes that occur during Bax activation, we determined the crystal structure of a Bax peptide bound to the 6A7 Fab fragment to a resolution of 2.3 A. The structure reveals the conformation of the 6A7 peptide epitope on Bax in the activated form and elucidates the extensive structural changes that Bax must undergo during the conversion from its native to its activated conformation.
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109
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Luo H, Dai S, Bonnesen PV, Haverlock TJ, Moyer BA, Buchanan AC. A Striking Effect of Ionic‐Liquid Anions in the Extraction of Sr2+ and Cs+ by Dicyclohexano‐18‐Crown‐6. SOLVENT EXTRACTION AND ION EXCHANGE 2006. [DOI: 10.1080/07366290500388624] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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110
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Toh SLI, McFarlane J, Tsouris C, DePaoli DW, Luo H, Dai S. Room‐Temperature Ionic Liquids in Liquid–Liquid Extraction: Effects of Solubility in Aqueous Solutions on Surface Properties. SOLVENT EXTRACTION AND ION EXCHANGE 2006. [DOI: 10.1080/07366290500388400] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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111
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Ravi P, Wang C, Dai S, Tam KC. Self-assembly of well-defined mono and dual end-capped C(60) containing polyacrylic acids in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:7167-74. [PMID: 16893212 DOI: 10.1021/la0606345] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Well-defined stimuli-responsive mono and dual fullerene (C(60)) end-capped poly(acrylic acid)s (PAA-C(60) and C(60)-PAA-C(60)) were synthesized by reacting C(60) with well-defined mono and dual azide end-functionalized poly(tert-butyl acrylate)s, followed by hydrolysis. The aggregation behaviors of these C(60) end-capped polymers in aqueous solution were examined using potentiometric and conductometric titrations and static and dynamic light scattering as well as transmission electron microscopy (TEM). Both PAA-C(60) and C(60)-PAA-C(60) show pH-responsive and water-soluble properties at high pH. Both polymers self-assemble to form large compound micelles (LCMs) in aqueous solutions. The LCMs of PAA-C(60) exist as "compact aggregates", whereas the LCMs of C(60)-PAA-C(60) possess a "core-shell" structure with a larger size and aggregation number. The micelles for both polymers swell upon neutralization, where the R(h) of PAA-C(60) micelles increases from approximately 44 to approximately 102 nm and the R(h) of C(60)-PAA-C(60) aggregates varies from approximately 89 to approximately 128 nm with increasing degree of neutralization. The lower swelling of the dual end-capped C(60)-PAA-C(60) system is related to its higher C(60) content, which enhances the interpolymer chain hydrophobic association that restrains the swelling of micellar aggregates.
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112
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Xu J, Wang P, Zhong X, Dai S, Sun H, Hao Y. Comparison of PAH and nonylphenol uptake by carp (Cyprinus carpio) and semipermeable membrane devices (SPMDs) from water. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2006; 77:211-8. [PMID: 16977522 DOI: 10.1007/s00128-006-1052-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Accepted: 06/05/2006] [Indexed: 05/11/2023]
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113
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Borghese CM, Werner DF, Topf N, Baron NV, Henderson LA, Boehm SL, Blednov YA, Saad A, Dai S, Pearce RA, Harris RA, Homanics GE, Harrison NL. An isoflurane- and alcohol-insensitive mutant GABA(A) receptor alpha(1) subunit with near-normal apparent affinity for GABA: characterization in heterologous systems and production of knockin mice. J Pharmacol Exp Ther 2006; 319:208-18. [PMID: 16807363 DOI: 10.1124/jpet.106.104406] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Volatile anesthetics and alcohols enhance transmission mediated by gamma-aminobutyric acid type A receptors (GABA(A)Rs) in the central nervous system, an effect that may underlie some of the behavioral actions of these agents. Substituting a critical serine residue within the GABA(A)R alpha(1) subunit at position 270 with the larger residue histidine eliminated receptor modulation by isoflurane, but it also affected receptor gating (increased GABA sensitivity). To correct the shift in GABA sensitivity of this mutant, we mutated a second residue, leucine at position 277 to alanine. The double mutant alpha(1)(S270H,L277A)beta(2)gamma(2S) GABA(A)R was expressed in Xenopus laevis oocytes and human embryonic kidney (HEK)293 cells, and it had near-normal GABA sensitivity. However, rapid application of a brief GABA pulse to receptors expressed in HEK293 cells revealed that the deactivation was faster in double mutant than in wild-type receptors. In all heterologous systems, the enhancing effect of isoflurane and ethanol was greatly decreased in the double mutant receptor. Homozygous knockin mice harboring the double mutation were viable and presented no overt abnormality, except hyperactivity. This knockin mouse line should be useful in determining which behavioral actions of volatile anesthetics and ethanol are mediated by the GABA(A)Rs containing the alpha(1) subunit.
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114
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Dai S, Eissa MA, Harrist RB, Labarthe DR. Difference in Associations of Bmi and its Fat-Free and Fat Components with Blood Lipids and Blood Pressure in Children and Adolescents: Project Heartbeat. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s10-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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115
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Xu J, Dai S, Han X, Sun S, Zhang P. Leaching of copper from an industrial sludge applied on a soil column. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2006; 76:663-70. [PMID: 16688550 DOI: 10.1007/s00128-006-0971-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Accepted: 02/06/2006] [Indexed: 05/09/2023]
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116
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Xu J, Han X, Sun S, Meng F, Dai S. Leaching behavior of copper (II) in a soil column experiment. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2005; 75:1028-33. [PMID: 16400594 DOI: 10.1007/s00128-005-0852-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Accepted: 09/19/2005] [Indexed: 05/06/2023]
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117
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Dai S, Keenan NL, Croft JB, Greenlund KJ, Labarthe DR. 035: Racial/Ethnic Disparities in Premature Death from the Leading Causes of Death in the United States, 2000. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s9b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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118
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Zhang Z, Rondinone AJ, Ma JX, Shen J, Dai S. Morphologically Templated Growth of Aligned Spinel CoFe 2 O 4 Nanorods. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2005; 17:1415-1419. [PMID: 34412436 DOI: 10.1002/adma.200500009] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Accepted: 03/07/2005] [Indexed: 06/13/2023]
Abstract
Uniaxially aligned CoFe2 O4 nanorods are obtained by coprecipitation of Co2+ , Fe2+ , and C2 O4 2- ions in a microemulsion solution, and subsequent high-temperature decomposition of CoFe2 (C2 O4 )3 . Each nanorod is made up of a "tectonic" assembly of CoFe2 O4 nanocrystals. Magnetization of such CoFe2 O4 materials may lead to their use in high-density magnetic recording media and high-performance electromagnetic and spintronic devices.
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119
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Tang Z, Chen H, Yang J, Dai S, Lin Y. The comparison of Ca2+/CaM-independent and Ca2+/CaM-dependent phosphorylation of myosin light chains by MLCK. Physiol Res 2005; 54:671-8. [PMID: 15717857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
The main regulatory mechanism of smooth muscle contraction involves Ca2+/calmodulin (CaM)-dependent phosphorylation of myosin (CDPM), by myosin light chain kinase (MLCK). It is also known that the increase in intracellular Ca2+ and phosphorylation of myosin occurs within a short time under physiological conditions, but the muscle tension may persist for a longer period of time. However, the mechanism of this phenomenon is still not clear. We hypothesize that MLCK also phosphorylates myosin in a Ca2+/CaM-independent manner (CIPM). The difference between CIPM and CDPM are as follows. Firstly, the extent of CIPM by MLCK was temperature-independent, whereas CDPM by MLCK was apparently decreasing with increasing temperature. Secondly, in contrast to the decreased extent of CDPM, the prolongation of incubation time did not decrease the extent of CIPM. Thirdly, a high concentration of K+ influences CIPM less than CDPM. Furthermore, the MLCK inhibitor ML-9 significantly inhibited CDPM by MLCK but not CIPM by MLCK. Lastly, arachidonic acid selectively increased CIPM by MLCK but not CDPM by MLCK. Finally, the activity of Mg2+-ATPase of myosin followed the sequence as this: CDPM>CIPM>unphosphorylated myosin. Our results revealed some primary features of CIPM by MLCK.
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120
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Tang Z, Chen H, Yang J, Dai S, Lin Y. The comparison of Ca2+/CaM-independent and Ca2+/CaM-dependent phosphorylation of myosin light chains by MLCK. Physiol Res 2005. [DOI: 10.33549/physiolres.930719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The main regulatory mechanism of smooth muscle contraction involves Ca2+/calmodulin (CaM)-dependent phosphorylation of myosin (CDPM), by myosin light chain kinase (MLCK). It is also known that the increase in intracellular Ca2+ and phosphorylation of myosin occurs within a short time under physiological conditions, but the muscle tension may persist for a longer period of time. However, the mechanism of this phenomenon is still not clear. We hypothesize that MLCK also phosphorylates myosin in a Ca2+/CaM-independent manner (CIPM). The difference between CIPM and CDPM are as follows. Firstly, the extent of CIPM by MLCK was temperature-independent, whereas CDPM by MLCK was apparently decreasing with increasing temperature. Secondly, in contrast to the decreased extent of CDPM, the prolongation of incubation time did not decrease the extent of CIPM. Thirdly, a high concentration of K+ influences CIPM less than CDPM. Furthermore, the MLCK inhibitor ML-9 significantly inhibited CDPM by MLCK but not CIPM by MLCK. Lastly, arachidonic acid selectively increased CIPM by MLCK but not CDPM by MLCK. Finally, the activity of Mg2+-ATPase of myosin followed the sequence as this: CDPM > CIPM > unphosphorylated myosin. Our results revealed some primary features of CIPM by MLCK.
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121
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Dai S, Ravi P, Tan CH, Tam KC. Self-assembly behavior of a stimuli-responsive water-soluble [60]fullerene-containing polymer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:8569-8575. [PMID: 15379476 DOI: 10.1021/la048826s] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A novel pH- and temperature-responsive water-soluble [60]fullerene-containing poly[2-(dimethylamino)ethyl methacrylate] (C60-b-PDMAEMA) was synthesized by atom transfer radical polymerization. The pH and temperature dependence of the physical properties of the aqueous C60-b-PDMAEMA solution was studied by potentiometric and conductometric titrations, UV-vis transmittance, and laser light scattering techniques. At low pH and at temperatures ranging from 25 to 55 degrees C, in addition to C60-b-PDMAEMA unimers, micelle-like aggregates are produced in the aqueous solution containing C60 hydrophobic cores and protonated PDMAEMA shells. Only unimeric C60-b-PDMAEMAs are found to exist in solution at high pH and low temperature, where PDMAEMA segments form a charge-transfer complex with C60 molecules. However, C60-b-PDMAEMA precipitates from aqueous solution at temperatures exceeding the lower critical solution temperature of PDMAEMA of approximately 45 degrees C. The pH and temperature stimuli-responsive properties of the [60]fullerene-containing polymer in aqueous solution are completely reversible.
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122
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Dai S, Tam KC, Wyn-Jones E, Jenkins RD. Isothermal Titration Calorimetric and Electromotive Force Studies on Binding Interactions of Hydrophobic Ethoxylated Urethane and Sodium Dodecyl Sulfate of Different Molecular Masses. J Phys Chem B 2004. [DOI: 10.1021/jp037144v] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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123
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Dai S, Tam KC. Isothermal titration calorimetric studies on the temperature dependence of binding interactions between poly(propylene glycol)s and sodium dodecyl sulfate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:2177-83. [PMID: 15835668 DOI: 10.1021/la0357559] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Isothermal titration calorimetry (ITC) is a sensitive research tool for examining the binding interactions between surfactant and polymer where the differential enthalpy during the binding process is monitored. In addition to the critical micelle concentration (cmc) and the micellization enthalpy (deltaHm), the effective micellar charge fraction (beta) of the ionic surfactant micellization process can also be determined from ITC thermograms. Poly(propylene glycol) (PPG) exhibits a lower critical solution temperature (LCST) ranging from 15 to 42 degrees C, depending on the molecular weights. We report, for the first time, the binding interactions between sodium dodecyl sulfate (SDS) and 1,000, 2,000 and 3,000 Da PPGs, where different binding mechanisms are in operation, depending on the temperature. At temperatures lower than the LCST, the binding interactions are similar to those of SDS and low molecular weight poly(ethylene glycol)s (MW < 3500 Da). At temperatures greater than the LCST, the binding interactions are dominated by direct solubilization of PPG chains into mixed micellar cores. At temperatures near the LCST, the binding interactions are controlled by the balance ofthe PPG solubilization at low SDS concentrations and polymer-induced micellization at high SDS concentrations.
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124
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Bao L, Mahurin SM, Haire RG, Dai S. Silver-Doped Sol−Gel Film as a Surface-Enhanced Raman Scattering Substrate for Detection of Uranyl and Neptunyl Ions. Anal Chem 2003; 75:6614-20. [PMID: 16465717 DOI: 10.1021/ac034791+] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A surface-enhanced Raman scattering (SERS) substrate containing silver particles was prepared by an acid-catalyzed sol-gel method. Silver nitrate was first doped into the sol-gel film followed by chemical reduction of the silver ions with sodium borohydride to produce silver particles. This silver-doped sol-gel substrate exhibits strong enhancement of Raman scattering from adsorbed uranyl ions with a detection limit of 8.5 x 10(-8) M, which is comparable to existing methods of uranyl detection such as spectrophotometry, fluorometry, and a SERS method based on ligand-modified solution silver colloids. However, in the present method, no preconcentration steps, chromogens, or complexing ligands are needed. Compared with the SERS method using Ag colloidal sols, the silver-doped sol-gel film has the advantage that the silver particles trapped in the sol-gel matrix are much more stable than Ag colloids in liquid media. Furthermore, porous silica sol-gel materials are known to have affinities toward many inorganic and organic molecules. The enhanced adsorption affinities could also lead to the increased SERS sensitivity. The performance of the new silver-doped sol-gel substrate was evaluated with uranyl ions and compared to that of a SERS substrate based on silver-coated silica beads prepared by vacuum deposition. The detection limit for the silver-doped sol-gel film was 104 times lower than that for the silver-coated silica beads. The sol-gel substrate was further used to obtain, for the first time, the surface-enhanced Raman spectrum of neptunyl ions in dilute aqueous solutions.
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125
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Dai S, Tam K. Isothermal titration calorimetric studies of alkyl phenol ethoxylate surfactants in aqueous solutions. Colloids Surf A Physicochem Eng Asp 2003. [DOI: 10.1016/j.colsurfa.2003.09.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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