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Sissaoui J, Efimov A, Kumpulainen T, Vauthey E. Photoinduced Electron Transfer in a Porphyrin-Fullerene Dyad at a Liquid Interface. J Phys Chem B 2022; 126:4723-4730. [PMID: 35727678 DOI: 10.1021/acs.jpcb.2c02405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The excited-state properties of an amphiphilic porphyrin-fullerene dyad and of its porphyrin analogue adsorbed at the dodecane/water interface are investigated by using surface second-harmonic generation. Although the porphyrin is formally centrosymmetric, the second-harmonic spectra of both compounds are dominated by the intense Soret band of the porphyrin. Polarization-selective measurements and molecular dynamics simulations suggest an angle of about 45° between the donor-acceptor axis and the interfacial plane, with the porphyrin interacting mostly with the nonpolar phase. Time-resolved measurements reveal a marked concentration dependence of the dynamics of both compounds upon Q-band excitation, indicating the occurrence of intermolecular quenching processes. The significant differences in dynamics and spectra between the dyad and the porphyrin analogue are explained by a self-quenching of the excited dyad via an intermolecular electron transfer.
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Affiliation(s)
- Jihad Sissaoui
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, 1205 Geneva, Switzerland
| | - Alexander Efimov
- Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33100 Tampere, Finland
| | - Tatu Kumpulainen
- Department of Chemistry/Nanoscience Center, University of Jyväskylä, Survontie 9 C, 40014 Jyväskylä, Finland
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, 1205 Geneva, Switzerland
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2
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Wagner JC, Hunter KM, Paesani F, Xiong W. Water Capture Mechanisms at Zeolitic Imidazolate Framework Interfaces. J Am Chem Soc 2021; 143:21189-21194. [PMID: 34878776 DOI: 10.1021/jacs.1c09097] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Water capture mechanisms of zeolitic imidazolate framework ZIF-90 are revealed by differentiating the water clustering and the center pore filling step, using vibrational sum-frequency generation spectroscopy (VSFG) at a one-micron spatial resolution and state-of-the-art molecular dynamics (MD) simulations. Through spectral line shape comparison between VSFG and IR spectra, the relative humidity dependence of VSFG intensity, and MD simulations, based on MB-pol, we found water clustering and center pore filling happen nearly simultaneously within each pore, with water filling the other pores sequentially. The integration of nonlinear optics with MD simulations provides critical mechanistic insights into the pore filling mechanism and suggests that the relative strength of the hydrogen bonds governs the water uptake mechanisms. This molecular-level detailed mechanism can inform the rational optimization of metal-organic frameworks for water harvesting.
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Affiliation(s)
- Jackson C Wagner
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Kelly M Hunter
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Francesco Paesani
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States.,Materials Science and Engineering Program, University of California, San Diego, California 92093, United States
| | - Wei Xiong
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States.,Materials Science and Engineering Program, University of California, San Diego, California 92093, United States.,Department of Electrical and Computer Engineering, University of California, San Diego, California 92093, United States
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3
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Qian Y, Deng GH, Lapp J, Rao Y. Interfaces of Gas-Aerosol Particles: Relative Humidity and Salt Concentration Effects. J Phys Chem A 2019; 123:6304-6312. [PMID: 31253043 DOI: 10.1021/acs.jpca.9b03896] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The growth of aerosol particles is intimately related to chemical reactions in the gas phase and particle phase and at gas-aerosol particle interfaces. While chemical reactions in gas and particle phases are well documented, there is very little information regarding interface-related reactions. The interface of gas-aerosol particles not only facilitates a physical channel for organic species to enter and exit but also provides a necessary lane for culturing chemical reactions. The physical and chemical properties of gas-particle interfaces have not been studied extensively, nor have the reactions occurring at the interfaces been well researched. This is mainly due to the fact that there is a lack of suitable in situ interface-sensitive analytical techniques for direct measurements of interfacial properties. The motivation behind this research is to understand how interfaces play a role in the growth of aerosol particles. We have developed in situ interface-specific second harmonic scattering to examine interfacial behaviors of molecules of aerosol particles under different relative humidity (RH) and salt concentrations. Both the relative humidity and salt concentration can change the particle size and the phase of the aerosol. RH not only varies the concentration of solutes inside aerosol particles but also changes interfacial hydration in local regions. Organic molecules were found to exhibit distinct behaviors at the interfaces and bulk on NaCl particles under different RH levels. Our quantitative analyses showed that the interfacial adsorption free energies remain unchanged while interfacial areas increase as the relative humidity increases. Furthermore, the surface tension of NaCl particles decreases as the RH increases. Our experimental findings from the novel nonlinear optical scattering technique stress the importance of interfacial water behaviors on aerosol particles in the atmosphere.
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Affiliation(s)
- Yuqin Qian
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Gang-Hua Deng
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Jordan Lapp
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Yi Rao
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
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4
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Khadria A, Fleischhauer J, Boczarow I, Wilkinson JD, Kohl MM, Anderson HL. Porphyrin Dyes for Nonlinear Optical Imaging of Live Cells. iScience 2018; 4:153-163. [PMID: 30240737 PMCID: PMC6147020 DOI: 10.1016/j.isci.2018.05.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 05/09/2018] [Accepted: 05/22/2018] [Indexed: 11/28/2022] Open
Abstract
Second harmonic generation (SHG)-based probes are useful for nonlinear optical imaging of biological structures, such as the plasma membrane. Several amphiphilic porphyrin-based dyes with high SHG coefficients have been synthesized with different hydrophilic head groups, and their cellular targeting has been studied. The probes with cationic head groups localize better at the plasma membrane than the neutral probes with zwitterionic or non-charged ethylene glycol-based head groups. Porphyrin dyes with only dications as hydrophilic head groups localize inside HEK293T cells to give SHG, whereas tricationic dyes localize robustly at the plasma membrane of cells, including neurons, in vitro and ex vivo. The copper(II) complex of the tricationic dye with negligible fluorescence quantum yield works as an SHG-only dye. The free-base tricationic dye has been demonstrated for two-photon fluorescence and SHG-based multimodal imaging. This study demonstrates the importance of a balance between the hydrophobicity and hydrophilicity of amphiphilic dyes for effective plasma membrane localization.
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Affiliation(s)
- Anjul Khadria
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Jan Fleischhauer
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Igor Boczarow
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - James D Wilkinson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Michael M Kohl
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Harry L Anderson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK.
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5
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Tran RJ, Sly KL, Conboy JC. Applications of Surface Second Harmonic Generation in Biological Sensing. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:387-414. [PMID: 28301745 DOI: 10.1146/annurev-anchem-071015-041453] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Surface second harmonic generation (SHG) is a coherent, nonlinear optical technique that is well suited for investigations of biomolecular interactions at interfaces. SHG is surface specific due to the intrinsic symmetry constraints on the nonlinear process, providing a distinct analytical advantage over linear spectroscopic methods, such as fluorescence and UV-Visible absorbance spectroscopies. SHG has the ability to detect low concentrations of analytes, such as proteins, peptides, and small molecules, due to its high sensitivity, and the second harmonic response can be enhanced through the use of target molecules that are resonant with the incident (ω) and/or second harmonic (2ω) frequencies. This review describes the theoretical background of SHG, and then it discusses its sensitivity, limit of detection, and the implementation of the method. It also encompasses the applications of surface SHG directed at the study of protein-surface, small-molecule-surface, and nanoparticle-membrane interactions, as well as molecular chirality, imaging, and immunoassays. The versatility, high sensitivity, and surface specificity of SHG show great potential for developments in biosensors and bioassays.
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Affiliation(s)
- Renee J Tran
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112;
| | - Krystal L Sly
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112;
| | - John C Conboy
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112;
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6
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Voylov DN, Holt AP, Doughty B, Bocharova V, Meyer HM, Cheng S, Martin H, Dadmun M, Kisliuk A, Sokolov AP. Unraveling the Molecular Weight Dependence of Interfacial Interactions in Poly(2-vinylpyridine)/Silica Nanocomposites. ACS Macro Lett 2017; 6:68-72. [PMID: 35632893 DOI: 10.1021/acsmacrolett.6b00915] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The structure and polymer-nanoparticle interactions among physically adsorbed poly(2-vinylpyridine) chains on the surface of silica nanoparticles (NPs) were systematically studied as a function of molecular weight (MW) by sum frequency generation (SFG) and X-ray photoelectron (XPS) spectroscopies. Analysis of XPS data identified hydrogen bonds between the polymer and NPs, while SFG evaluated the change in the number of free OH sites on the NP's surface. Our data revealed that the hydrogen bonds and amount of the free -OH sites have a significant dependence on the polymer's MW. These results provide clear experimental evidence that the interaction of physically adsorbed chains with nanoparticles is strongly MW dependent and aids in unraveling the microscopic mechanism responsible for the strong MW dependence of dynamics of the interfacial layer in polymer nanocomposites.
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Affiliation(s)
- Dmitry N. Voylov
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Adam P. Holt
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Benjamin Doughty
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Vera Bocharova
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Harry M. Meyer
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Shiwang Cheng
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Halie Martin
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Mark Dadmun
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Alexander Kisliuk
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
| | - Alexei P. Sokolov
- Department of Chemistry and ‡Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916-1600, United States
- Chemical Sciences Division and ∥Materials Science
and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States
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7
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Doughty B, Yin P, Ma YZ. Adsorption, Ordering, and Local Environments of Surfactant-Encapsulated Polyoxometalate Ions Probed at the Air-Water Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:8116-22. [PMID: 27452922 DOI: 10.1021/acs.langmuir.6b01643] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The continued development and application of surfactant-encapsulated polyoxometalates (SEPs) relies on understanding the ordering and organization of species at their interface and how these are impacted by the various local environments to which they are exposed. Here, we report on the equilibrium properties of two common SEPs adsorbed to the air-water interface and probed with surface-specific vibrational sum-frequency generation (SFG) spectroscopy. These results reveal clear shifts in vibrational band positions, the magnitude of which scales with the charge of the SEP core, which is indicative of a static field effect on the surfactant coating and the associated local chemical environment. This static field also induces ordering in surrounding water molecules that is mediated by charge screening via the surface-bound surfactants. From these SFG measurements, we are able to show that Mo132-based SEPs are more polar than Mo72V30 SEPs. Disorder in the surfactant chain packing at the highly curved SEP surfaces is attributed to large conic volumes that can be sampled without interactions with neighboring chains. Measurements of adsorption isotherms yield free energies of adsorption to the air-water interface of -46.8 ± 0.4 and -44.8 ± 1.2 kJ/mol for the Mo132 and Mo72V30 SEPs, respectively, indicating a strong propensity for the fluid surface. The influence of intermolecular interactions on the surface adsorption energies is discussed.
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Affiliation(s)
- Benjamin Doughty
- Chemical Sciences Division, ‡Chemical and Engineering Materials Division, Neutron Sciences Directorate, and §Shull Wollan Center, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Panchao Yin
- Chemical Sciences Division, ‡Chemical and Engineering Materials Division, Neutron Sciences Directorate, and §Shull Wollan Center, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, ‡Chemical and Engineering Materials Division, Neutron Sciences Directorate, and §Shull Wollan Center, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
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8
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Nuriya M, Fukushima S, Momotake A, Shinotsuka T, Yasui M, Arai T. Multimodal two-photon imaging using a second harmonic generation-specific dye. Nat Commun 2016; 7:11557. [PMID: 27156702 PMCID: PMC4865818 DOI: 10.1038/ncomms11557] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 04/07/2016] [Indexed: 11/09/2022] Open
Abstract
Second harmonic generation (SHG) imaging can be used to visualize unique biological phenomena, but currently available dyes limit its application owing to the strong fluorescent signals that they generate together with SHG. Here we report the first non-fluorescent and membrane potential-sensitive SHG-active organic dye Ap3. Ap3 is photostable and generates SH signals at the plasma membrane with virtually no fluorescent signals, in sharp contrast to the previously used fluorescent dye FM4-64. When tested in neurons, Ap3-SHG shows linear membrane potential sensitivity and fast responses to action potentials, and also shows significantly reduced photodamage compared with FM4-64. The SHG-specific nature of Ap3 allows simultaneous and completely independent imaging of SHG signals and fluorescent signals from various reporter molecules, including markers of cellular organelles and intracellular calcium. Therefore, this SHG-specific dye enables true multimodal two-photon imaging in biological samples. Current dyes for second harmonic generation (SHG) imaging strongly fluoresce, limiting their application. Here the authors develop a SHG-specific dye, Ap3, that partitions into cell membranes, displays sensitivity to membrane potential and has virtually no fluorescence emission at SHG imaging wavelengths.
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Affiliation(s)
- Mutsuo Nuriya
- Department of Pharmacology School of Medicine, Keio University, 35 Shinanomachi, Tokyo 160-8582, Japan.,Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama 240-8501, Japan
| | - Shun Fukushima
- Graduate School of Pure and Applied Sciences and Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tsukuba 305-8577, Japan
| | - Atsuya Momotake
- Graduate School of Pure and Applied Sciences and Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tsukuba 305-8577, Japan
| | - Takanori Shinotsuka
- Department of Pharmacology School of Medicine, Keio University, 35 Shinanomachi, Tokyo 160-8582, Japan
| | - Masato Yasui
- Department of Pharmacology School of Medicine, Keio University, 35 Shinanomachi, Tokyo 160-8582, Japan
| | - Tatsuo Arai
- Graduate School of Pure and Applied Sciences and Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tsukuba 305-8577, Japan
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9
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Licari G, Brevet PF, Vauthey E. Fluorescent DNA probes at liquid/liquid interfaces studied by surface second harmonic generation. Phys Chem Chem Phys 2016; 18:2981-92. [DOI: 10.1039/c5cp06151b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The excited-state properties of oxazole yellow DNA probes change substantially when going from bulk water to the dodecane/water interface.
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Affiliation(s)
- Giuseppe Licari
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
| | - Pierre-François Brevet
- Institut Lumière Matière
- UMR CNRS 5306
- Université Claude Bernard
- Lyon 1
- Campus LyonTech – La Doua
| | - Eric Vauthey
- Department of Physical Chemistry
- University of Geneva
- CH-1211 Geneva 4
- Switzerland
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10
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Dadap JI, Eisenthal KB. Probing the relative orientation of molecules bound to DNA by second-harmonic generation. J Phys Chem B 2014; 118:14366-72. [PMID: 25379958 DOI: 10.1021/jp507834s] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We develop a model to probe the relative orientation of two second-order polarizable daunomycin molecules that are intercalated into a DNA duplex using optical second-harmonic (SH) generation. The SH field generated by the daunomycin molecules interfere with each other. Because the interference depends on the relative orientation of the daunomycin molecules, we can control the interference by changing the number of base pairs separating them. The relative orientation changes as the number of base pairs separating them, multiplied by 36°, which is the twist angle between neighboring base pairs. In this paper, we derive a set of relationships between the relative angle of the molecules and the nonlinear susceptibility elements, and we calculate the SH field generated by the DNA/molecular-pair complex attached to an isotropic dielectric sphere. Calculations reveal that the SH intensity varies periodically with the relative orientation of the two chromophores in the plane perpendicular to the helical axis. The predicted periodicity is in close agreement with experimental results. Structural changes induced by foreign molecules binding to DNA will change the relative orientation of the two chromophores and thereby change the SH interference pattern. We discuss the potential of this SH interference method in providing a new way to probe structural changes induced by the formation of biomolecule complexes. An important feature of the method is that it is label-free, that is, the binding molecule, in this case, daunomycin, is not tagged.
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Affiliation(s)
- Jerry Icban Dadap
- Departments of †Applied Physics and Applied Mathematics and ‡Chemistry, Columbia University , New York, New York 10027, United States
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Abstract
The transacting activator of transduction (TAT) protein plays a key role in the progression of AIDS. Studies have shown that a +8 charged sequence of amino acids in the protein, called the TAT peptide, enables the TAT protein to penetrate cell membranes. To probe mechanisms of binding and translocation of the TAT peptide into the cell, investigators have used phospholipid liposomes as cell membrane mimics. We have used the method of surface potential sensitive second harmonic generation (SHG), which is a label-free and interface-selective method, to study the binding of TAT to anionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-1'-rac-glycerol (POPG) and neutral 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes. It is the SHG sensitivity to the electrostatic field generated by a charged interface that enabled us to obtain the interfacial electrostatic potential. SHG together with the Poisson-Boltzmann equation yielded the dependence of the surface potential on the density of adsorbed TAT. We obtained the dissociation constants Kd for TAT binding to POPC and POPG liposomes and the maximum number of TATs that can bind to a given liposome surface. For POPC Kd was found to be 7.5 ± 2 μM, and for POPG Kd was 29.0 ± 4.0 μM. As TAT was added to the liposome solution the POPC surface potential changed from 0 mV to +37 mV, and for POPG it changed from -57 mV to -37 mV. A numerical calculation of Kd, which included all terms obtained from application of the Poisson-Boltzmann equation to the TAT liposome SHG data, was shown to be in good agreement with an approximated solution.
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Roy S, Covert PA, FitzGerald WR, Hore DK. Biomolecular Structure at Solid–Liquid Interfaces As Revealed by Nonlinear Optical Spectroscopy. Chem Rev 2014; 114:8388-415. [DOI: 10.1021/cr400418b] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Sandra Roy
- Department
of Chemistry, University of Victoria, Victoria, British Columbia, V8W 3V6 Canada
| | - Paul A. Covert
- Department
of Chemistry, University of Victoria, Victoria, British Columbia, V8W 3V6 Canada
| | - William R. FitzGerald
- Department
of Chemistry, University of Victoria, Victoria, British Columbia, V8W 3V6 Canada
| | - Dennis K. Hore
- Department
of Chemistry, University of Victoria, Victoria, British Columbia, V8W 3V6 Canada
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