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Zhang H, Liu D, Zhang J, Adams E, Gong J, Li W, Wang B, Liu X, Yang R, Wei F, Allen HC. GMP affected assembly behaviors of phosphatidylethanolamine monolayers elucidated by multi-resolved SFG-VS and BAM. Colloids Surf B Biointerfaces 2024; 241:113995. [PMID: 38870647 DOI: 10.1016/j.colsurfb.2024.113995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/18/2024] [Accepted: 05/26/2024] [Indexed: 06/15/2024]
Abstract
The interaction between nucleotide molecules and lipid molecules plays important roles in cell activities, but the molecular mechanism is very elusive. In the present study, a small but noticeable interaction between the negatively charged phosphatidylethanolamine (PE) and Guanosine monophosphate (GMP) molecules was observed from the PE monolayer at the air/water interface. As shown by the sum frequency generation (SFG) spectra and Pi-A isotherm of the PE monolayer, the interaction between the PE and GMP molecules imposes very small changes to the PE molecules. However, the Brewster angle microscopy (BAM) technique revealed that the assembly conformations of PE molecules are significantly changed by the adsorption of GMP molecules. By comparing the SFG spectra of PE monolayers after the adsorption of GMP, guanosine and guanine, it is also shown that the hydrogen bonding effect plays an important role in the nucleotide-PE interactions. These results provide fundamental insight into the structure changes during the nucleotide-lipid interaction, which may shed light on the molecular mechanism of viral infection, DNA drug delivery, and cell membrane curvature control in the brain or neurons.
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Affiliation(s)
- Hongjuan Zhang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Dongqi Liu
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Jiawei Zhang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Ellen Adams
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
| | - Jingjing Gong
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Wenhui Li
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Bing Wang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Xueqing Liu
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Renqiang Yang
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China
| | - Feng Wei
- School of Optoelectronic Materials and Technology, & Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, Jianghan University, Wuhan 430056, China.
| | - Heather C Allen
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA.
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2
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Lu H, Macht M, Rosenberg R, Wiedenbeck E, Lukas M, Qi D, Maltseva D, Zahn D, Cölfen H, Bonn M. Organic Nucleation: Water Rearrangement Reveals the Pathway of Ibuprofen. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2307858. [PMID: 38269485 DOI: 10.1002/smll.202307858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/31/2023] [Indexed: 01/26/2024]
Abstract
The organic nucleation of the pharmaceutical ibuprofen is investigated, as triggered by the protonation of ibuprofen sodium salt at elevated pH. The growth and aggregation of nanoscale solution species by Analytical Ultracentrifugation and Molecular Dynamics (MD) simulations is tracked. Both approaches reveal solvated molecules, oligomers, and prenucleation clusters, their size as well as their hydration at different reaction stages. By combining surface-specific vibrational spectroscopy and MD simulations, water interacting with ibuprofen at the air-water interface during nucleation is probed. The results show the structure of water changes upon ibuprofen protonation in response to the charge neutralization. Remarkably, the water structure continues to evolve despite the saturation of protonated ibuprofen at the hydrophobic interface. This further water rearrangement is associated with the formation of larger aggregates of ibuprofen molecules at a late prenucleation stage. The nucleation of ibuprofen involves ibuprofen protonation and their hydrophobic assembly. The results highlight that these processes are accompanied by substantial water reorganization. The critical role of water is possibly relevant for organic nucleation in aqueous environments in general.
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Affiliation(s)
- Hao Lu
- Department of Materials and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, Zhejiang Province, 314001, P. R. China
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Moritz Macht
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Rose Rosenberg
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Eduard Wiedenbeck
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Max Lukas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daizong Qi
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daria Maltseva
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Dirk Zahn
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Helmut Cölfen
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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3
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Golbek TW, Okur HI, Kulik S, Dedic J, Roke S, Weidner T. Lysozyme Interaction with Phospholipid Nanodroplets Probed by Sum Frequency Scattering Vibrational Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6447-6454. [PMID: 37125843 DOI: 10.1021/acs.langmuir.3c00276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
When a nanoparticle (NP) is introduced into a biological environment, its identity and interactions are immediately attributed to the dense layer of proteins that quickly covers the particle. The formation of this layer, dubbed the protein corona, is in general a combination of proteins interacting with the surface of the NP and a contest between other proteins for binding sites either at the surface of the NP or upon the dense layer. Despite the importance for surface engineering and drug development, the molecular mechanisms and structure behind interfacial biomolecule action have largely remained elusive. We use ultrafast sum frequency scattering (SFS) spectroscopy to determine the structure and the mode of action by which these biomolecules interact with and manipulate interfaces. The majority of work in the field of sum frequency generation has been done on flat model interfaces. This limits some important membrane properties such as membrane fluidity and dimensionality─important factors in biomolecule-membrane interactions. To move toward three-dimensional (3D) nanoscopic interfaces, we utilize SFS spectroscopy to interrogate the surface of 3D lipid monolayers, which can be used as a model lipid-based nanocarrier system. In this study, we have utilized SFS spectroscopy to follow the action of lysozyme. SFS spectra in the amide I region suggest that there is lysozyme at the interface and that the lysozyme induces an increased lipid monolayer order. The binding of lysozyme with the NP is demonstrated by an increase in acyl chain order determined by the ratio of the CH3 symmetric and CH2 symmetric peak amplitudes. Furthermore, the lipid headgroup orientation s-PO2- change strongly supports lysozyme insertion into the lipid layer causing lipid disruption and reorientation. Altogether, with SFS, we have made a huge stride toward understanding the binding and structure change of proteins within the protein corona.
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Affiliation(s)
| | - Halil I Okur
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bio-engineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Department of Chemistry and National Nanotechnology Research Center (UNAM), Bilkent University, 06800 Ankara, Turkey
| | - Sergey Kulik
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bio-engineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jan Dedic
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bio-engineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Sylvie Roke
- Laboratory for Fundamental BioPhotonics (LBP), Institute of Bio-engineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering (IMX), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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4
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Sun M, Liu D, Yin G, Li W, Zhou Y, Lu W, Chen Y, Zhang H, Wei F. Magnesium Ion Responses of Zwitterionic Phosphatidylethanolamine Head and Tail Groups Elucidated by Frequency-Resolved SFG-VS. J Phys Chem Lett 2023; 14:2433-2440. [PMID: 36862126 DOI: 10.1021/acs.jpclett.2c03593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
In the present study, the effects of magnesium ions on the conformational changes of the deuterated 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine (D54-DMPE) monolayer were elucidated by frequency-resolved sum frequency generation vibrational spectroscopy (SFG-VS) and surface pressure-area isotherm measurements. It is found that the tilt angles of the methyl in tail groups decrease, while the tilt angles of the phosphate and methylene in head groups increase during the compression of the DMPE monolayers at both the air/water interface and the air/MgCl2 solution interfaces. It is also shown that the tilt angle of the methyl in the tail groups slightly decreases, while the tilt angles of the phosphate and methylene in the head groups significantly increase as the MgCl2 concentration increases from 0 to 1.0 M. These results indicate that both the tail groups and the head groups of the DMPE molecules become closer to the surface normal, as the MgCl2 concentration increases in the subphase.
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Affiliation(s)
- Meng Sun
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Dongqi Liu
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Guogeng Yin
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Wenhui Li
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Youhua Zhou
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Wangting Lu
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Yijie Chen
- College of Food Science and Technology & Key Laboratory of Environment Correlative Dietology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hongjuan Zhang
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
| | - Feng Wei
- School of Optoelectronic Materials and Technology & Institute of Interdisciplinary Research, Jianghan University, Wuhan 430056, China
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5
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Navakauskas E, Niaura G, Strazdaite S. Effect of deuteration on a phosphatidylcholine lipid monolayer structure: New insights from vibrational sum-frequency generation spectroscopy. Colloids Surf B Biointerfaces 2022; 220:112866. [PMID: 36174490 DOI: 10.1016/j.colsurfb.2022.112866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/07/2022] [Accepted: 09/19/2022] [Indexed: 10/14/2022]
Abstract
We used vibrational sum-frequency generation (VSFG) spectroscopy to elucidate the possible effect of various levels of isotopic substitution (H/D) on the properties of the DPPC monolayer by probing DPPC/D2O interface. We found that deuteration of the choline group has a great impact on monolayer properties, while monolayers with deuterated alkyl chains do not exhibit any differences under our experimental conditions. In addition, deuteration of the choline group strongly affected the hydration of the phosphate group. We showed by probing symmetric stretching vibration of phosphate group that denser packing only slightly reduced the hydration of DPPC-d13 and DPPC-d75 monolayers. Moreover, addition of calcium ions, which generally cause a marked dehydration of the lipid monolayer, had no effect on lipid monolayers with deuterated choline group. We proposed that one way to explain this experimental finding could be deuteration induced changes in the structure of lipid's choline group, resulting in a well-hydrated but Ca2+ ion blocking structure. These results have important implications for various spectroscopic techniques, which commonly use deuteration of phospholipids to circumvent overlapping between vibrational bands.
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Affiliation(s)
- Edvinas Navakauskas
- Department of Organic Chemistry, Center for Physical Sciences and Technology (FTMC), Saulėtekis ave. 3, LT-10257 Vilnius, Lithuania
| | - Gediminas Niaura
- Department of Organic Chemistry, Center for Physical Sciences and Technology (FTMC), Saulėtekis ave. 3, LT-10257 Vilnius, Lithuania.
| | - Simona Strazdaite
- Department of Organic Chemistry, Center for Physical Sciences and Technology (FTMC), Saulėtekis ave. 3, LT-10257 Vilnius, Lithuania
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6
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Maltseva D, Gonella G, Ruysschaert JM, Bonn M. Phospholipid acyl tail affects lipid headgroup orientation and membrane hydration. J Chem Phys 2022; 156:234706. [PMID: 35732527 DOI: 10.1063/5.0092237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Biomembrane hydration is crucial for understanding processes at biological interfaces. While the effect of the lipid headgroup has been studied extensively, the effect (if any) of the acyl chain chemical structure on lipid-bound interfacial water has remained elusive. We study model membranes composed of phosphatidylethanolamine (PE) and phosphatidylcholine (PC) lipids, the most abundant lipids in biomembranes. We explore the extent to which the lipid headgroup packing and associated water organization are affected by the lipid acyl tail unsaturation and chain length. To this end, we employ a combination of surface-sensitive techniques, including sum-frequency generation spectroscopy, surface pressure measurements, and Brewster angle microscopy imaging. Our results reveal that the acyl tail structure critically affects the headgroup phosphate orientational distribution and lipid-associated water molecules, for both PE and PC lipid monolayers at the air/water interface. These insights reveal the importance of acyl chain chemistry in determining not only membrane fluidity but also membrane hydration.
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Affiliation(s)
- Daria Maltseva
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Grazia Gonella
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Jean-Marie Ruysschaert
- Laboratory for the Structure and Function of Biological Membranes, Université Libre de Bruxelles, Boulevard du Triomphe, 1050 Brussels, Belgium
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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7
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Hou Y, Li J, Li B, Yuan Q, Gan W. Combined Second Harmonic Generation and Fluorescence Analyses of the Structures and Dynamics of Molecules on Lipids Using Dual-Probes: A Review. Molecules 2022; 27:molecules27123778. [PMID: 35744902 PMCID: PMC9231091 DOI: 10.3390/molecules27123778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 01/25/2023] Open
Abstract
Revealing the structures and dynamic behaviors of molecules on lipids is crucial for understanding the mechanism behind the biophysical processes, such as the preparation and application of drug delivery vesicles. Second harmonic generation (SHG) has been developed as a powerful tool to investigate the molecules on various lipid membranes, benefiting from its natural property of interface selectivity, which comes from the principle of even order nonlinear optics. Fluorescence emission, which is in principle not interface selective but varies with the chemical environment where the chromophores locate, can reveal the dynamics of molecules on lipids. In this contribution, we review some examples, which are mainly from our recent works focusing on the application of combined spectroscopic methods, i.e., SHG and two-photon fluorescence (TPF), in studying the dynamic behaviors of several dyes or drugs on lipids and surfactants. This review demonstrates that molecules with both SHG and TPF efficiencies may be used as intrinsic dual-probes in plotting a clear physical picture of their own behaviors, as well as the dynamics of other molecules, on lipid membranes.
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Affiliation(s)
- Yi Hou
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, China; (Y.H.); (J.L.); (B.L.)
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Jianhui Li
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, China; (Y.H.); (J.L.); (B.L.)
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Bifei Li
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, China; (Y.H.); (J.L.); (B.L.)
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Qunhui Yuan
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, China;
| | - Wei Gan
- Shenzhen Key Laboratory of Flexible Printed Electronics Technology, School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen 518055, China; (Y.H.); (J.L.); (B.L.)
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
- Correspondence:
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8
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Wang H, Hu XH, Wang HF. Temporal and Chirp Effects of Laser Pulses on the Spectral Lineshape in Sum-Frequency Generation Vibrational Spectroscopy. J Chem Phys 2022; 156:204706. [DOI: 10.1063/5.0088506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Assignment and interpretation of the sum-frequency generation vibrational spectra (SFG-VS) depend on the ability to measure and understand the factors affecting the SFG-VS spectral lineshape accurately and reliably. In the past, the formulation of the polarization selection rules for SFG-VS and the development of the sub-wavenumber high-resolution broadband SFG-VS (HR-BB-SFG-VS) have provided solutions for many of these needs. However, despite these advantages, HR-BB-SFG-VS has not been widely adopted. The majority of SFG measurements so far still relies on the picosecond scanning SFG-VS (ps-SFG-VS) or the conventional broadband SFG-VS (BB-SFG-VS) with the spectral resolution around (mostly above) 10 cm-1, which also results in less ideal spectral lineshape in the SFG spectra due to the temporal and chirp effects of the laser pulses used in experiment. In this report, the temporal and the chirp effects of laser pulses with different profiles in the SFG experiment on the measured SFG-VS spectral lineshape are examined through spectral simulation. In addition, the experimental data of a classical model system, i.e., OTS (octadecyltrichlorosilane) monolayer on glass, obtained from the ps-SFG-VS, the BB-SFG-VS, and the HR-BB-SFG-VS measurements, are directly compared and examined. These results show that temporal and chirp effects are often significant in the conventional BB-SFG-VS, resulting lineshape distortions and peak position shifts besides spectral broadening. Such temporal and chirp effects are less significant in the ps scanning SFG-VS. For the HR-BB-SFG-VS, spectral broadening, and temporal and chirp effects are insignificant, making HR-BB-SFG-VS the choice for accurate and reliable measurement and analysis of SFG-VS spectra.
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9
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Li P, Wang L, Sun M, Yao J, Li W, Lu W, Zhou Y, Zhang G, Hu C, Zheng W, Wei F. Binding affinity and conformation of a conjugated AS1411 aptamer at a cationic lipid bilayer interface. Phys Chem Chem Phys 2022; 24:9018-9028. [PMID: 35381056 DOI: 10.1039/d1cp05753g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aptamers have been widely used in the detection, diagnosis, and treatment of cancer. Owing to their special binding affinity toward cancer-related biomarkers, aptamers can be used for targeted drug delivery or bio-sensing/bio-imaging in various scenarios. The interfacial properties of aptamers play important roles in controlling the surface charge, recognition efficiency, and binding affinity of drug-delivering lipid-based carriers. In this research, the interfacial behaviors, such as surface orientation, molecular conformation, and adsorption kinetics of conjugated AS1411 molecules at different cationic lipid bilayer interfaces were investigated by sum frequency generation vibrational spectroscopy (SFG-VS) in situ and in real-time. It is shown that the conjugated AS1411 molecules at the DMTAP bilayer interface show a higher binding affinity but with slower binding kinetics compared to the DMDAP bilayer interface. The analysis results also reveal that the thymine residues of cholesteryl conjugated AS1411 molecules show higher conformational ordering compared to the thymine residues of the alkyl chain conjugated AS1411 molecules. These understandings provide unique molecular insight into the aptamer-lipid membrane interactions, which may help researchers to improve the efficiency and safety of aptamer-related drug delivery systems.
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Affiliation(s)
- Penghua Li
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Liqun Wang
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Meng Sun
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Jiyuan Yao
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Wenhui Li
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China. .,Institution for Interdisciplinary Research, Jianghan University, Wuhan, Hubei, 430056, China
| | - Wangting Lu
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China. .,Institution for Interdisciplinary Research, Jianghan University, Wuhan, Hubei, 430056, China
| | - Youhua Zhou
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Geng Zhang
- Department of Chemistry, College of Science, Huazhong Agricultural University, No. 1, Shizishan Street, Wuhan 430070, China
| | - Chenglong Hu
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China.
| | - Wanquan Zheng
- Institution for Interdisciplinary Research, Jianghan University, Wuhan, Hubei, 430056, China.,Institut des Sciences Moléculaires d'Orsay, Université Paris-Sud, 91405 Orsay Cedex, France
| | - Feng Wei
- Key Laboratory of Optoelectronic Chemical Materials and Devices, Ministry of Education, & School of Optoelectronic Materials and Technology, Jianghan University, Wuhan 430056, China. .,Institution for Interdisciplinary Research, Jianghan University, Wuhan, Hubei, 430056, China
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10
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Sofińska K, Lupa D, Chachaj-Brekiesz A, Czaja M, Kobierski J, Seweryn S, Skirlińska-Nosek K, Szymonski M, Wilkosz N, Wnętrzak A, Lipiec E. Revealing local molecular distribution, orientation, phase separation, and formation of domains in artificial lipid layers: Towards comprehensive characterization of biological membranes. Adv Colloid Interface Sci 2022; 301:102614. [PMID: 35190313 DOI: 10.1016/j.cis.2022.102614] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/28/2022] [Accepted: 02/01/2022] [Indexed: 01/01/2023]
Abstract
Lipids, together with molecules such as DNA and proteins, are one of the most relevant systems responsible for the existence of life. Selected lipids are able to assembly into various organized structures, such as lipid membranes. The unique properties of lipid membranes determine their complex functions, not only to separate biological environments, but also to participate in regulatory functions, absorption of nutrients, cell-cell communication, endocytosis, cell signaling, and many others. Despite numerous scientific efforts, still little is known about the reason underlying the variability within lipid membranes, and its biochemical significance. In this review, we discuss the structural complexity of lipid membranes, as well as the importance to simplify studied systems in order to understand phenomena occurring in natural, complex membranes. Such systems require a model interface to be analyzed. Therefore, here we focused on analytical studies of artificial systems at various interfaces. The molecular structure of lipid membranes, specifically the nanometric thickens of molecular bilayer, limits in a major extent the choice of highly sensitive methods suitable to study such structures. Therefore, we focused on methods that combine high sensitivity, and/or chemical selectivity, and/or nanometric spatial resolution, such as atomic force microscopy, nanospectroscopy (tip-enhanced Raman spectroscopy, infrared nanospectroscopy), phase modulation infrared reflection-absorption spectroscopy, sum-frequency generation spectroscopy. We summarized experimental and theoretical approaches providing information about molecular structure and composition, lipid spatial distribution (phase separation), organization (domain shape, molecular orientation) of lipid membranes, and real-time visualization of the influence of various molecules (proteins, drugs) on their integrity. An integral part of this review discusses the latest achievements in the field of lipid layer-based biosensors.
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11
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Golbek TW, Schmüser L, Rasmussen MH, Poulsen TB, Weidner T. Lasalocid Acid Antibiotic at a Membrane Surface Probed by Sum Frequency Generation Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:3184-3192. [PMID: 32069059 DOI: 10.1021/acs.langmuir.9b03752] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Carboxyl polyether ionophores (CPIs) are widely used as veterinary antibiotics and to increase food utilization in ruminating animals. Furthermore, CPIs can target drug-resistant bacteria, but detailed knowledge about their mode-of-action is needed to develop agents with a reasonable therapeutic index. It has been suggested that ionophores bind to membranes and incur large structural changes to shield a bound ion from the hydrophobic environment of the lipid bilayer for transport. One crucial piece of information is missing, however: Is it necessary for the free ionophore to adsorb on the membrane surface before interacting with a cation to facilitate cross-membrane ion transport? To answer this question, we applied sum-frequency generation (SFG) vibrational spectroscopy and surface tensiometry to identify the interaction between the prototypical CPI lasalocid acid (LA) and a model membrane. Observed changes in the surface pressure demonstrate that the free LA undergoes a self-assembly process with the lipid monolayer. Spectra taken from the lipid monolayer show that the free acid inserts partially into the lipid monolayer and then after complexation with sodium chloride disrupts the lipid monolayer. Overall, this study strongly suggests that this must be the crucial step of LA and metal ion complexation that allows the ionophore to traverse a lipid membrane.
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Affiliation(s)
| | - Lars Schmüser
- Department of Chemistry, Aarhus University, 8000 Aarhus, Denmark
| | | | - Thomas B Poulsen
- Department of Chemistry, Aarhus University, 8000 Aarhus, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000 Aarhus, Denmark
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12
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Ojha D, Kaliannan NK, Kühne TD. Time-dependent vibrational sum-frequency generation spectroscopy of the air-water interface. Commun Chem 2019. [DOI: 10.1038/s42004-019-0220-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Abstract
Vibrational sum-frequency generation spectroscopy is a powerful method to study the microscopic structure and dynamics of interfacial systems. Here we demonstrate a simple computational approach to calculate the time-dependent, frequency-resolved vibrational sum-frequency generation spectrum (TD-vSFG) of the air-water interface. Using this approach, we show that at the air-water interface, the transition of water molecules with bonded OH modes to free OH modes occurs at a time scale of $$\sim$$
~
3 ps, whereas water molecules with free OH modes rapidly make a transition to a hydrogen-bonded state within $$\sim$$
~
2 ps. Furthermore, we also elucidate the origin of the observed differential dynamics based on the time-dependent evolution of water molecules in the different local solvent environments.
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13
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Li P, Shen Y, Wang L, Lu W, Li W, Chen K, Zhou Y, Shen L, Wei F, Zheng W. The electric double layer structure modulates poly-dT 25 conformation and adsorption kinetics at the cationic lipid bilayer interface. SOFT MATTER 2019; 15:4445-4453. [PMID: 31011740 DOI: 10.1039/c9sm00321e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The conformation and adsorption kinetics of oligonucleotides at lipid membrane interfaces are crucial to their biological functions, but are yet not clearly understood. Poly-dT oligonucleotide molecules have been widely used as primers for reverse translation of RNA molecules, as well as a surface recognition agent for mRNA purification and extraction. In this research, the adsorption processes of poly-dT25 on lipid membranes in different ionic solutions were investigated by sum frequency generation vibrational spectroscopy (SFG-VS) together with a single molecule tracking technique in situ and in real time. These systematic studies provide us with molecular insight into the chemical and physical nature of oligonucleotide-membrane interactions, and show us how the electric double layer (EDL) structure changes the conformation and adsorption kinetics of oligonucleotides. The SFG-VS results indicate that an increase of ionic concentration not only decreases the adsorption density of oligonucleotides but also changes the conformation of oligonucleotides from an elongated conformation to a coiled conformation, causing stronger thermodynamic interactions with membranes, as demonstrated by single molecule tracking techniques. It is also shown that the ionic solution can tune the balance between the surface diffusion rate and solution diffusion rate of oligonucleotides significantly. These results demonstrated that the spectra and kinetics collected by in situ label-free SFG-VS detection and the single molecular tracking technique can provide new molecular insights into the mechanisms of oligonucleotide-membrane interactions. These new understandings may help researchers to control the assembly of oligonucleotide-liposome complexes and to improve the efficiency of transportation and delivery of oligonucleotide molecules.
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Affiliation(s)
- PengHua Li
- Institution for Interdisciplinary Research, & Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Jianghan University, Wuhan, Hubei 430056, China.
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14
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Ma Y, Hou J, Hao W, Liu J, Meng L, Lu Z. Influence of riboflavin on the oxidation kinetics of unsaturated fatty acids at the air/aqueous interface revealed by sum frequency generation vibrational spectroscopy. Phys Chem Chem Phys 2019; 20:17199-17207. [PMID: 29900453 DOI: 10.1039/c8cp00975a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Riboflavin, a common nutrient also known as vitamin B2, is known to potentially play important roles in preventing lipid peroxidations. However, the detailed antioxidant mechanisms, especially the influence of riboflavin on lipid oxidations at biological interfaces, have not yet been fully explored. In the current study, the effect of riboflavin molecules on the oxidation kinetics of monounsaturated cis-11-eicosenoic acid (EA) at the air/water interface was systematically investigated using sum frequency generation vibrational spectroscopy (SFG-VS). It was discovered that the oxidation rates of the interfacial EA molecules can be reduced by about two to three times in the presence of riboflavin in the aqueous subphase. Further SFG-VS measurements under the protection of nitrogen purging gas showed that more tightly packed and ordered monolayer structures were formed by the surface adsorption of riboflavin molecules, making the C[double bond, length as m-dash]C bonds less accessible to the gas phase oxidative species. These results suggested that the antioxidant mechanism for riboflavin in the vicinity of biomembranes may not necessarily involve other reducing agents. They also show the great importance of interfacial molecular structures in biologically relevant chemical reactions.
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Affiliation(s)
- Yingxue Ma
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
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15
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Chen Y, Okur HI, Lütgebaucks C, Roke S. Zwitterionic and Charged Lipids Form Remarkably Different Structures on Nanoscale Oil Droplets in Aqueous Solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1042-1050. [PMID: 29019694 DOI: 10.1021/acs.langmuir.7b02896] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The molecular structure of zwitterionic and charged monolayers on small oil droplets in aqueous solutions is determined using a combined second harmonic and sum frequency study. From the interfacial vibrational signature of the acyl chains and phosphate headgroups as well as the response of the hydrating water, we find that zwitterionic and charged lipids with identical acyl chains form remarkably different monolayers. Zwitterionic phospholipids form a closely packed monolayer with highly ordered acyl tails. In contrast, the charged phospholipids form a monolayer with a low number density and disordered acyl tails. The charged headgroups are oriented perpendicular to the monolayer rather than parallel, as is the case for zwitterionic lipids. These significant differences between the two types of phospholipids indicate important roles of phospholipid headgroups in the determination of properties of cellular membranes and lipid droplets. The observed behavior of charged phospholipids is different from expectations based on studies performed on extended planar interfaces, at which condensed monolayers are readily formed. The difference can be explained by nanoscale related changes in charge condensation behavior that has its origin in a different balance of interfacial intermolecular interactions.
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Affiliation(s)
- Yixing Chen
- Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Halil I Okur
- Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Cornelis Lütgebaucks
- Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Sylvie Roke
- Laboratory for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), and Institute of Materials Science (IMX), School of Engineering (STI), and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
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16
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Wang L, Shen Y, Yang Y, Lu W, Li W, Wei F, Zheng G, Zhou Y, Zheng W, Cao Y. Stern-Layer Adsorption of Oligonucleotides on Lamellar Cationic Lipid Bilayer Investigated by Polarization-Resolved SFG-VS. ACS OMEGA 2017; 2:9241-9249. [PMID: 30023605 PMCID: PMC6045418 DOI: 10.1021/acsomega.7b01214] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 11/29/2017] [Indexed: 06/08/2023]
Abstract
The molecular interaction between the oligonucleotides and lipid membranes is the key to the functions of virus, aptamer, and various oligonucleotide-based materials. In this study, the conformational changes of oligonucleotides (dT25) on lamellar cationic 1,2-dimyristoyl-3-trimethylammonium-propane (DMTAP) bilayer were investigated by polarization-resolved sum frequency generation vibrational spectroscopy (SFG-VS) in situ. The SFG-VS spectra within different wavenumber ranges were analyzed to give conformation details of thymine groups, phosphate groups, and OD/OH groups and to provide a comprehensive and fundamental understanding of the oligonucleotide adsorption on a model bilayer. It is shown that the adsorption of dT25 on DMTAP bilayer reaches maximum at CdT ≈ 500 nM. And the conformation of dT25 molecules change significantly when surface charge of DMTAP bilayer reaches the point of zero charge (PZC) at CdT ≈ 100 nM. Combined spectroscopic evidences also indicate that the formation of electric double layer at the DMTAP/dT25 surface follows the Gouy-Chapman-Stern model. The analysis results also show that the symmetric PO2- stretching mode of oligonucleotide molecules can serve as a sensitive vibration molecular probe for quantifying the oligonucleotide/lipid charge ratio and determine the point of zero charge (PZC) of lipid bilayer surface, which may help researchers to control the layer-by-layer assembly of oligonucleotide-lipid complexes and to improve the efficiency genetic therapy against cancer and viral infections.
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Affiliation(s)
- Liqun Wang
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Yang Shen
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Yanbo Yang
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Wangting Lu
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Wenhui Li
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Feng Wei
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Guang Zheng
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Youhua Zhou
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
| | - Wanquan Zheng
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
- Institut
des Sciences Moléculaires d’Orsay, Université Paris-Sud, 91405 Orsay Cedex, France
| | - Yuancheng Cao
- Institution
for Interdisciplinary Research, & Key Laboratory
of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Life
Science, School of Physics and Information Engineering, and School of Chemical and Environmental
Engineering, Jianghan University, 430056 Wuhan, Hubei, P. R. China
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17
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Chase HM, Chen S, Fu L, Upshur MA, Rudshteyn B, Thomson RJ, Wang HF, Batista VS, Geiger FM. Orientations of nonlocal vibrational modes from combined experimental and theoretical sum frequency spectroscopy. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.01.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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18
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Licari G, Cwiklik L, Jungwirth P, Vauthey E. Exploring Fluorescent Dyes at Biomimetic Interfaces with Second Harmonic Generation and Molecular Dynamics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3373-3383. [PMID: 28314372 DOI: 10.1021/acs.langmuir.7b00403] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The adsorption of a DNA fluorescent probe belonging to the thiazole orange family at the dodecane/water and dodecane/phospholipid/water interfaces has been investigated using a combination of surface second harmonic generation (SSHG) and all-atomistic molecular dynamics (MD) simulations. Both approaches point to a high affinity of the cationic dye for the dodecane/water interface with a Gibbs free energy of adsorption on the order of -45 kJ/mol. Similar affinity was observed with a monolayer of negatively charged DPPG (1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol)) lipids. On the other hand, no significant adsorption could be found with the zwitterionic DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) lipids. This was rationalized in terms of Coulombic interactions between the monolayer surface and the cationic dye. The similar affinity for the interface with and without DPPG, despite the favorable Coulombic attraction in the latter case, could be explained after investigating the interfacial orientation of the dye. In the absence of a monolayer, the dye adsorbs with its molecular plane almost flat at the interface, whereas in the presence of DPPG it has to intercalate into the monolayer and adopt a significantly different orientation to benefit from the electrostatic stabilization.
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Affiliation(s)
- Giuseppe Licari
- Department of Physical Chemistry, University of Geneva , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Lukasz Cwiklik
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences , Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences , Flemingovo nam. 2, 16610 Prague 6, Czech Republic
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
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Wei F, Xia WX, Hu ZJ, Li WH, Zhang JY, Zheng WQ. Laser Linewidth and Spectral Resolution in Infrared Scanning Sum Frequency Generation Vibrational Spectroscopy System. CHINESE J CHEM PHYS 2016. [DOI: 10.1063/1674-0068/29/cjcp1601001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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