1
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Chattopadhyay M, Krok E, Orlikowska-Rzeznik H, Piatkowski L. Cooperativity between sodium ions and water molecules facilitates lipid mobility in model cell membranes. Chem Sci 2023; 14:4002-4011. [PMID: 37063804 PMCID: PMC10094088 DOI: 10.1039/d2sc06836b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Cellular membranes are surrounded by an aqueous buffer solution containing various ions, which influence the hydration layer of the lipid head groups. At the same time, water molecules hydrating the lipids play a major role in facilitating the organisation and dynamics of membrane lipids. Employing fluorescence microscopy imaging and fluorescence recovery after photobleaching measurements, we demonstrate that the cooperativity between water and sodium (Na+) ions is crucial to maintain lipid mobility upon the removal of the outer hydration layer of the lipid membrane. Under similar hydration conditions, lipid diffusion ceases in the absence of Na+ ions. We find that Na+ ions (and similarly K+ ions) strengthen the water clathrate cage around the lipid phosphocholine headgroup and thus prevent its breaking upon removal of bulk water. Intriguingly, Ca2+ and Mg2+ do not show this effect. In this article, we provide a detailed molecular-level picture of ion specific dependence of lipid mobility and membrane hydration properties.
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Affiliation(s)
| | - Emilia Krok
- Institute of Physics, Poznan University of Technology Piotrowo 3 60-965 Poznan Poland
| | | | - Lukasz Piatkowski
- Institute of Physics, Poznan University of Technology Piotrowo 3 60-965 Poznan Poland
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2
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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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3
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Han XF, Sun WH, Wang SJ, Lu XL. Sum frequency spectroscopy studies on cell membrane fusion induced by divalent cations. CHINESE J CHEM PHYS 2022. [DOI: 10.1063/1674-0068/cjcp2110213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cell membrane fusion is a fundamental biological process involved in a number of cellular living functions. Regarding this, divalent cations can induce fusion of the lipid bilayers through binding and bridging of divalent cations to the charged lipids, thus leading to the cell membrane fusion. How-ever, the elaborate mechanism of cell membrane fusion induced by divalent cations is still needed to be elucidated. Here, surface/interface sensitive sum frequency generation vibrational spectroscopy (SFG-VS) and dynamic light scattering (DLS) were applied in this research to study the responses of phospholipid monolayer to the exposure of divalent metal ions i.e. Ca2+ and Mg2+. According to the particle size distribution results measured by DLS experiments, it was found that Ca2+ could induce inter-vesicular fusion while Mg2+ could not. An octadecyltrichlorosilane self-assembled monolayer (OTS SAM)-lipid monolayer system was designed to model the cell membrane for the SFG-VS experiment. Ca2+ could interact with the lipid PO2− head groups more strongly, resulting in cell membrane fusion more easily, in comparison with Mg2+. No specific interaction between the two metal cations and the C=O groups was observed. However, the C=O orientations changed more after Ca2+-PO2− binding than Mg2+ mediation on lipid monolayer. Meanwhile, Ca2+ could induce dehydration of the lipids (which should be related to the strong Ca2+-PO2− interaction), leading to the reduced hindrance for cell membrane fusion.
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Affiliation(s)
- Xiao-feng Han
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, National Demonstration Center for Experimental, Biomedical Engineering Education, Southeast University, Nanjing 210096, China
| | - Wen-hua Sun
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, National Demonstration Center for Experimental, Biomedical Engineering Education, Southeast University, Nanjing 210096, China
| | - Shu-jing Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, National Demonstration Center for Experimental, Biomedical Engineering Education, Southeast University, Nanjing 210096, China
| | - Xiao-lin Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, National Demonstration Center for Experimental, Biomedical Engineering Education, Southeast University, Nanjing 210096, China
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4
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Rimoli CV, de Oliveira Pedro R, Miranda PB. Interaction mechanism of chitosan oligomers in pure water with cell membrane models studied by SFG vibrational spectroscopy. Colloids Surf B Biointerfaces 2022; 219:112782. [PMID: 36063719 DOI: 10.1016/j.colsurfb.2022.112782] [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: 05/18/2022] [Revised: 08/10/2022] [Accepted: 08/17/2022] [Indexed: 11/20/2022]
Abstract
Chitosan is a versatile and biocompatible cationic antimicrobial polymer obtained from sustainable sources that is effective against a wide range of microorganisms. Although it is soluble only at low pH, chitosan oligomers (ChitO) are soluble in pure water and thus more appropriate for antibacterial applications. Although there is a vast literature on chitosan's antimicrobial activity, the molecular details of its interaction with biomembranes remain unclear. Here we investigate these molecular interactions by resorting to phospholipid Langmuir films (zwitterionic DPPC and anionic DPPG) as simplified membrane models (for mammalian and bacterial membranes, respectively), and using SFG vibrational spectroscopy to probe lipid tail conformation, headgroup dynamics and interfacial water orientation. For comparison, we also investigate the interactions of another simple cationic antimicrobial polyelectrolyte, poly(allylamine) hydrochloride - PAH. By forming the lipid films over the polyelectrolyte solutions, we found that both have only a very small interaction with DPPC, but PAH adsorption is able to invert the interfacial water orientation (membrane potential). This might explain why ChitO is compatible with mammalian cells, while PAH is toxic. In contrast, their interaction with DPPG films is much stronger, even more so for ChitO, with both insertion within the lipid film and interaction with the oppositely charged headgroups. Again, PAH adsorption inverts the membrane potential, while ChitO does not. Finally, ChitO interaction with DPPG is weaker if the antimicrobial is injected underneath a pre-assembled Langmuir film, and its interaction mode depends on the time interval between end of film compression and ChitO injection. These differences between ChitO and PAH effects on the model membranes highlight the importance of molecular structure and intermolecular interactions for their bioactivity, and therefore this study may provide insights for the rational design of more effective antimicrobial molecules.
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Affiliation(s)
- Caio Vaz Rimoli
- Sao Carlos Physics Institute, University of Sao Paulo, CP 369, Sao Carlos CEP 13560-970, SP, Brazil; Laboratoire Kastler Brossel, ENS-Université PSL, CNRS, Sorbonne Université, College de France, 24 Rue Lhomond, F-75005 Paris, France
| | - Rafael de Oliveira Pedro
- Sao Carlos Physics Institute, University of Sao Paulo, CP 369, Sao Carlos CEP 13560-970, SP, Brazil; Department of exact and earth sciences, Minas Gerais State University (UEMG), Ituiutaba CEP 38302-192, MG, Brazil
| | - Paulo B Miranda
- Sao Carlos Physics Institute, University of Sao Paulo, CP 369, Sao Carlos CEP 13560-970, SP, Brazil.
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5
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Cheng V, Conboy JC. Inhibitory Effect of Lanthanides on Native Lipid Flip-Flop. J Phys Chem B 2022; 126:7651-7663. [PMID: 36129784 DOI: 10.1021/acs.jpcb.2c04039] [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 influence of ytterbium ions (Yb3+), a commonly used paramagnetic NMR chemical shift reagent, on the physical properties and flip-flop kinetics of dipalmitoylphosphatidylcholine (DPPC) planar supported lipid bilayers (PSLBs) was investigated. Langmuir isotherm studies revealed that Yb3+ interacts strongly with the phosphate headgroup of DPPC, evidenced by the increases in shear and compression moduli. Using sum-frequency vibrational spectroscopy, changes in the acyl chain ordering and phase transition temperature were also observed, consistent with Yb3+ interacting with the phosphate headgroup of DPPC. The changes in the physical properties of the membrane were also observed to be concentration dependent, with more pronounced modification observed at low (50 μM) Yb3+ concentrations compared to 6.5 mM Tb3+, suggesting a cross-linking mechanism between adjacent DPPC lipids. Additionally, the changes in membrane packing and phase transition temperatures in the presence of Tris buffer suggested that a putative Yb(Tris)3+ complex forms that coordinates to the PC headgroup. The kinetics of DPPC flip-flop in the gel and liquid crystalline (lc) phases were substantially inhibited in the presence of Yb3+, regardless of the Yb3+ concentration. Analysis of the flip-flop kinetics under the framework of transition state theory revealed that the free energy barrier to flip-flop in both the gel and lc phases was substantial increased over a pure DPPC membrane. In the gel phase, the trend in the free energy barrier appeared to follow the trend in the shear moduli, suggesting that the Yb3+-DPPC headgroup interaction was driving the increase in the activation free energy barrier. In the lc phase, activation free energies of DPPC flip-flop in the presence of 50 μM or 6.5 mM Yb3+ were found to mirror the free energies of TEMPO-DPPC flip-flop, leading to the conclusion that the strong interaction between Yb3+ and the PC headgroup was essentially manifested as a headgroup charge modification. These studies illustrate that the presence of the lanthanide Yb3+ results in significant modification to the lipid membrane physical properties and, more importantly, results in a pronounced inhibition of native lipid flip-flop.
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Affiliation(s)
- Victoria Cheng
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - John C Conboy
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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6
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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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7
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Li Y, Feng R, Liu M, Guo Y, Zhang Z. Mechanism by Which Cholesterol Induces Sphingomyelin Conformational Changes at an Air/Water Interface. J Phys Chem B 2022; 126:5481-5489. [PMID: 35839485 DOI: 10.1021/acs.jpcb.2c03127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This work investigates the interactions in cholesterol and sphingomyelin monolayers at the molecular level by high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The SFG spectra of natural egg sphingomyelin (ESM) as a function of cholesterol concentration are obtained at an air/water interface under different polarization combinations. The analysis of the spectra shows that cholesterol can induce sphingomyelin conformational changes at an air/water interface. The mechanism is proposed. When cholesterol is inserted into the ESM monolayer, the inherent intramolecular hydrogen bonds between the phosphate moiety and 3OH in the sphingosine backbones are destroyed. During this process, the sphingosine backbones become more ordered, while the conformation of the N-linked long acid chain remains unaltered. The OH of the cholesterol head group can bind to the -PO-2 of the ESM molecule, and the orientation of the -PO-2 in the head groups changes to be more parallel to the interface.
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Affiliation(s)
- Yiyi Li
- Beijing National Laboratory for Molecular Sciences, Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rongjuan Feng
- Beijing National Laboratory for Molecular Sciences, Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Minghua Liu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuan Guo
- Beijing National Laboratory for Molecular Sciences, Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhen Zhang
- Beijing National Laboratory for Molecular Sciences, Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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8
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Du R, Li X, Ma YH, Luo Y, Wang C, Ma Q, Lu X. Exploring Interfacial Hydrolysis of Artificial Neutral Lipid Monolayer and Bilayer Catalyzed by Phospholipase C. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:8104-8113. [PMID: 35749224 DOI: 10.1021/acs.langmuir.2c00995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Phospholipase C (PLC) represents an important type of enzymes with the feature of hydrolyzing phospholipids at the position of the glycerophosphate bond, among which PLC extracted from Bacillus cereus (BC-PLC) has been extensively studied owing to its similarity to hitherto poorly characterized mammalian analogues. This study focuses on investigating the interfacial hydrolysis mechanism of phosphatidylcholine (PC) monolayer and bilayer membranes catalyzed by BC-PLC using sum frequency generation vibrational spectroscopy (SFG-VS) and laser scanning confocal microscopy (LSCM). We found that, upon interfacial hydrolysis, BC-PLC was adsorbed onto the lipid interface and catalyzed the lipolysis with no net orientation, as evidenced by the silent amide I band, indicating that ordered PLC alignment was not a prerequisite for the enzyme activity, which is very different from what we have reported for phospholipase A1 (PLA1) and phospholipase A2 (PLA2) [Kai, S. Phys. Chem. Chem. Phys. 2018, 20(1), 63-67; Wang, F. Langmuir 2019, 35(39), 12831-12838; Zhang, F. Langmuir 2020, 36(11), 2946-2953]. For the PC monolayer, one of the two hydrolysates, phosphocholine, desorbed from the interface into the aqueous phase, while the other one, diacylglycerol (DG), stayed well packed with high order at the interface. For the PC bilayer, phosphocholine dispersed into the aqueous phase too, similar to the monolayer case; however, DG, presumably formed clusters with the unreacted lipid substrates and desorbed from the interface. With respect to both the monolayer and bilayer cases, mechanistic schematics were presented to illustrate the different interfacial hydrolysis processes. Therefore, this model experimental study in vitro provides significant molecular-level insights and contributes necessary knowledge to reveal the lipolysis kinetics with respect to PLC and lipid membranes with monolayer and bilayer structures.
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Affiliation(s)
- Rongrong Du
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
| | - Xu Li
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
| | - Yong-Hao Ma
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
| | - Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
| | - Chu Wang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
| | - Qian Ma
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, Nanjing 210029, P. R. China
- Department of General Dentistry, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing 210029, P. R. China
| | - Xiaolin Lu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, P. R. China
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9
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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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10
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Kumal RR, Wimalasiri PN, Servis MJ, Uysal A. Thiocyanate Ions Form Antiparallel Populations at the Concentrated Electrolyte/Charged Surfactant Interface. J Phys Chem Lett 2022; 13:5081-5087. [PMID: 35653184 DOI: 10.1021/acs.jpclett.2c00934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Anions play significant roles in the separation of lanthanides and actinides. The molecular-scale details of how these anions behave at aqueous interfaces are not well understood, especially at high ionic strengths. Here, we describe the interfacial structure of thiocyanate anions at a soft charged interface up to 5 M bulk concentration with combined classical and phase-sensitive vibrational sum frequency generation (PS-VSFG) spectroscopy and molecular dynamics (MD) simulations. At low concentrations thiocyanate ions are mostly oriented with their sulfur end pointing toward the charged surfactants. The VSFG signal reaches a plateau at around 100 mM bulk concentration, followed by significant changes above 1 M. At high concentrations a new thiocyanate population emerges with their sulfur end pointing toward the bulk liquid. The -CN stretch frequency is different for up and down oriented SCN- ions, indicating different coordination environments. These results provide key molecular-level insights for the interfacial behavior of complex anions in highly concentrated solutions.
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Affiliation(s)
- Raju R Kumal
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Pubudu N Wimalasiri
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Michael J Servis
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Ahmet Uysal
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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11
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Judd KD, Gonzalez NM, Yang T, Cremer PS. Contact Ion Pair Formation Is Not Necessarily Stronger than Solvent Shared Ion Pairing. J Phys Chem Lett 2022; 13:923-930. [PMID: 35050629 DOI: 10.1021/acs.jpclett.1c03576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Vibrational sum frequency spectroscopy (VSFS) and pressure-area Langmuir trough measurements were used to investigate the binding of alkali metal cations to eicosyl sulfate (ESO4) surfactants in monolayers at the air/water interface. The number density of sulfate groups could be tuned by mixing the anionic surfactant with eicosanol. The equilibrium dissociation constant for K+ to the fatty sulfate interface showed 10 times greater affinity than for Li+ and approximately 3 times greater than for Na+. All three cations formed solvent shared ion pairs when the mole fraction of ESO4 was 0.33 or lower. Above this threshold charge density, Li+ formed contact ion pairs with the sulfate headgroups, presumably via bridging structures. By contrast, K+ only bound to the sulfate moieties in solvent shared ion pairing configurations. The behavior for Na+ was intermediate. These results demonstrate that there is not necessarily a correlation between contact ion pair formation and stronger binding affinity.
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Affiliation(s)
- Kenneth D Judd
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Nicole M Gonzalez
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Tinglu Yang
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Paul S Cremer
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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12
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Deplazes E, Tafalla BD, Murphy C, White J, Cranfield CG, Garcia A. Calcium Ion Binding at the Lipid-Water Interface Alters the Ion Permeability of Phospholipid Bilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:14026-14033. [PMID: 34784471 DOI: 10.1021/acs.langmuir.1c02016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Calcium ions (Ca2+) play a fundamental role in membrane-associated physiological processes. Ca2+ can also significantly modulate the physicochemical properties of phospholipid bilayers, but whether this occurs at physiologically relevant concentrations is difficult to determine because of the uncertainty in the reported affinity of Ca2+ for phospholipid bilayers. In this article, we determine the apparent affinity of Ca2+ for zwitterionic phospholipid bilayers using tethered bilayer lipid membranes (tBLMs) used in conjunction with swept-frequency electrical impedance spectroscopy (EIS). We report that Ca2+ binds to phospholipid bilayers at physiologically relevant concentrations and modulates membrane permeability. We present direct experimental evidence that this effect is governed by specific interactions with select lipid headgroup moieties, which is supported by data from molecular dynamics (MD) simulations. This is the first reported use of tBLM/EIS to estimate cation-membrane affinity. Combined with MD simulations, this technique provides a novel methodology to elucidate the molecular details of cation-membrane interactions at the water-phospholipid interface.
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Affiliation(s)
- Evelyne Deplazes
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
| | | | - Christopher Murphy
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Jacqueline White
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Charles G Cranfield
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Alvaro Garcia
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia
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13
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Morris C, Kent TW, Shen F, Wojcikiewicz EP, Du D. Effects of the Hydrophilic N-Terminal Region on Aβ-Mediated Membrane Disruption. J Phys Chem B 2021; 125:7671-7678. [PMID: 34252282 DOI: 10.1021/acs.jpcb.1c03413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Amyloidogenesis of amyloid-β (Aβ) peptides is intimately related to pathological neurodegeneration in Alzheimer's disease. Here, we investigated the membrane damage activity of Aβ40 and its derivatives that contain mutation at the N-terminal charged residues using a membrane leakage assay. A model 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) phospholipid vesicle encapsulating the fluorescent dye carboxyfluorescein was used in the study. Our results show that the mutations of the N-terminal charged residues of Aβ40 significantly affect the peptide-induced membrane leakage. The results suggest that favorable electrostatic interactions of the N-terminal charged residues and the phosphatidylcholine membrane surface are crucial in Aβ-mediated membrane permeation. The flexible and charge-rich N-terminal region may play a critical role in directing Aβ self-association on the membrane surface and in anchoring and stabilizing the peptide aggregates inserted in the phospholipid membrane, which are closely related with membrane disruption activity of Aβ. The results provide new mechanistic insight into the Aβ-mediated membrane damage process, which may be critical for understanding the mechanism of Aβ neurotoxicity in Alzheimer's disease.
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Affiliation(s)
- Clifford Morris
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Thomas W Kent
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Fengyun Shen
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Ewa P Wojcikiewicz
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Deguo Du
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
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14
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Abstract
The ubiquity of aqueous solutions in contact with charged surfaces and the realization that the molecular-level details of water-surface interactions often determine interfacial functions and properties relevant in many natural processes have led to intensive research. Even so, many open questions remain regarding the molecular picture of the interfacial organization and preferential alignment of water molecules, as well as the structure of water molecules and ion distributions at different charged interfaces. While water, solutes and charge are present in each of these systems, the substrate can range from living tissues to metals. This diversity in substrates has led to different communities considering each of these types of aqueous interface. In this Review, by considering water in contact with metals, oxides and biomembranes, we show the essential similarity of these disparate systems. While in each case the classical mean-field theories can explain many macroscopic and mesoscopic observations, it soon becomes apparent that such theories fail to explain phenomena for which molecular properties are relevant, such as interfacial chemical conversion. We highlight the current knowledge and limitations in our understanding and end with a view towards future opportunities in the field.
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15
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Szekeres GP, Krekic S, Miller RL, Mero M, Pagel K, Heiner Z. The interaction of chondroitin sulfate with a lipid monolayer observed by using nonlinear vibrational spectroscopy. Phys Chem Chem Phys 2021; 23:13389-13395. [PMID: 34105546 PMCID: PMC8207512 DOI: 10.1039/d1cp01975a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The first vibrational sum-frequency generation (VSFG) spectra of chondroitin sulfate (CS) interacting with dipalmitoyl phosphatidylcholine (DPPC) at air–liquid interface are reported here, collected at a laser repetition rate of 100 kHz. By studying the VSFG spectra in the regions of 1050–1450 cm−1, 2750–3180 cm−1, and 3200–3825 cm−1, it was concluded that in the presence of Ca2+ ions, the head groups together with the head-group-bound water molecules in the DPPC monolayer are strongly influenced by the interaction with CS, while the organization of the phospholipid tails remains mostly unchanged. The interactions were observed at a CS concentration below 200 nM, which exemplifies the potential of VSFG in studying biomolecular interactions at low physiological concentrations. The VSFG spectra recorded in the O–H stretching region at chiral polarization combination imply that CS molecules are organized into ordered macromolecular superstructures with a chiral secondary structure. Chondroitin sulfate interacts with the headgroups of a lipid monolayer at the air–liquid interface and shows a chiral secondary structure.![]()
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Affiliation(s)
- Gergo Peter Szekeres
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany. and Department of Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Szilvia Krekic
- School of Analytical Sciences Adlershof, Humboldt-Universität zu Berlin, Albert-Einstein-Straße 5-11, 12489 Berlin, Germany. and Institute of Biophysics, Biological Research Centre, Temesvári krt. 62, 6726, Szeged, Hungary and Doctoral School of Multidisciplinary Medical Sciences, University of Szeged, Dugonics tér 13, 6720, Szeged, Hungary
| | - Rebecca L Miller
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Mark Mero
- Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2a, 12489 Berlin, Germany
| | - Kevin Pagel
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany. and Department of Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Zsuzsanna Heiner
- School of Analytical Sciences Adlershof, Humboldt-Universität zu Berlin, Albert-Einstein-Straße 5-11, 12489 Berlin, Germany.
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16
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Gupta R, Singh A, Srihari V, Ghosh SK. Ionic Liquid-Induced Phase-Separated Domains in Lipid Multilayers Probed by X-ray Scattering Studies. ACS OMEGA 2021; 6:4977-4987. [PMID: 33644605 PMCID: PMC7905935 DOI: 10.1021/acsomega.0c06014] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 01/28/2021] [Indexed: 05/16/2023]
Abstract
A cellular membrane, primarily a lipid bilayer, surrounds the internal components of a biological cell from the external components. This self-assembled bilayer is known to be perturbed by ionic liquids (ILs) causing malfunctioning of a cellular organism. In the present study, surface-sensitive X-ray scattering techniques have been employed to understand this structural perturbation in a lipid multilayer system formed by a zwitterionic phospholipid, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine. The ammonium and phosphonium-based ILs with methanesulfonate anions are observed to induce phase-separated domains in the plane of a bilayer. The lamellar X-ray diffraction peaks suggest these domains to correlate across the bilayers in a smectic liquid crystalline phase. This induced IL-rich lamellar phase has a very low lamellar repeat distance, suggesting the formation of an interdigitated bilayer. The IL-poor phase closely related to the pristine lipid phase shows a decrement in the in-plane chain lattice parameters with a reduced tilt angle. The ammonium and phosphonium-based ILs with a relatively bulky anion, p-toluenemethanesulfonate, have shown a similar effect.
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Affiliation(s)
- Ritika Gupta
- Department
of Physics, School of Natural Sciences, Shiv Nadar University, NH 92, Tehsil Dadri, G. B. Nagar, Uttar Pradesh 201314, India
| | - Arnab Singh
- Surface
Physics and Material Science Division, Saha
Institute of Nuclear Physics, AF Block, Bidhannagar, Kolkata 700064, India
| | - Velaga Srihari
- High
Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Sajal K. Ghosh
- Department
of Physics, School of Natural Sciences, Shiv Nadar University, NH 92, Tehsil Dadri, G. B. Nagar, Uttar Pradesh 201314, India
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17
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Neal JF, Saha A, Zerkle MM, Zhao W, Rogers MM, Flood AH, Allen HC. Molecular Recognition and Hydration Energy Mismatch Combine To Inform Ion Binding Selectivity at Aqueous Interfaces. J Phys Chem A 2020; 124:10171-10180. [DOI: 10.1021/acs.jpca.0c09568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jennifer F. Neal
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ankur Saha
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mia M. Zerkle
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wei Zhao
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Mickey M. Rogers
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Amar H. Flood
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Heather C. Allen
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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18
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Poyton MF, Pullanchery S, Sun S, Yang T, Cremer PS. Zn 2+ Binds to Phosphatidylserine and Induces Membrane Blebbing. J Am Chem Soc 2020; 142:18679-18686. [PMID: 33078929 DOI: 10.1021/jacs.0c09103] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Herein, we show that Zn2+ binds to phosphatidylserine (PS) lipids in supported lipid bilayers (SLBs), forming a PS-Zn2+ complex with an equilibrium dissociation constant of ∼100 μM. Significantly, Zn2+ binding to SLBs containing more than 10 mol % PS induces extensive reordering of the bilayer. This reordering is manifest through bright spots of high fluorescence intensity that can be observed when the bilayer contains a dye-labeled lipid. Measurements using atomic force microscopy (AFM) reveal that these spots represent three-dimensional unilamellar blebs. Bleb formation is ion specific, inducible by exposing the bilayer to μM concentrations of Zn2+ but not Mg2+, Cu2+, Co2+, or Mn2+. Moreover, Ca2+ can induce some blebbing at mM concentrations but not nearly as effectively as Zn2+. The interactions of divalent metal cations with PS lipids were further investigated by a combination of vibrational sum frequency spectroscopy (VSFS) and surface pressure-area isotherm measurements. VSFS revealed that Zn2+ and Ca2+ were bound to the phosphate and carboxylate moieties on PS via contact ion pairing, dehydrating the lipid headgroup, whereas Mg2+ and Cu2+ were bound without perturbing the hydration of these functional groups. Additionally, Zn2+ was found to dramatically reduce the area per lipid in lipid monolayers, while Mg2+ and Cu2+ did not. Ca2+ could also reduce the area per lipid but only when significantly higher surface pressures were applied. These measurements suggest that Zn2+ caused lipid blebbing by decreasing the area per lipid on the side of the bilayer to which the salt was exposed. Such findings have implications for blebbing, fusion, oxidation, and related properties of PS-rich membranes in biological systems where Zn2+ concentrations are asymmetrically distributed.
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19
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Nakata S, Yamaguchi Y, Fukuhara K, Hishida M, Kitahata H, Katsumoto Y, Umino Y, Denda M, Kumazawa N. Characteristic responses of a 1,2-dioleoyl-sn-glycero-3-phosphocholine molecular layer to monovalent and divalent metal cations. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Ren HC, Yuan JN, Chen TN, Selvaraj G, Kaliamurthi S, Zhang XQ, Wei D, Ji GF, Zhang ZM. Computational insights of two‐dimensional infrared spectroscopy under electric fields in phosphorylcholine. INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY 2020. [DOI: 10.1002/qua.26169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Hai Chao Ren
- School of Physical SciencesUniversity of Science and Technology of China Hefei China
- National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid PhysicsChinese Academy of Engineering Physics Mianyang China
| | - Jiao Nan Yuan
- College of ScienceHenan University of Technology Zhengzhou China
| | - Tu Nan Chen
- The First Affiliated HospitalArmy Medical University Chongqing China
| | - Gurudeeban Selvaraj
- College of Food Science and EngineeringHenan University of Technology Zhengzhou China
| | - Satyavani Kaliamurthi
- College of Food Science and EngineeringHenan University of Technology Zhengzhou China
| | - Xiu Qing Zhang
- National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid PhysicsChinese Academy of Engineering Physics Mianyang China
- Institude of Atomic and Molecular Physics, College of Physical Science and TechnologySichuan University Chengdu China
| | - Dong‐Qing Wei
- College of Food Science and EngineeringHenan University of Technology Zhengzhou China
- College of Life Science and BiotechnologyShanghai Jiao Tong University Shanghai China
| | - Guang Fu Ji
- National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid PhysicsChinese Academy of Engineering Physics Mianyang China
| | - Zeng Ming Zhang
- School of Physical SciencesUniversity of Science and Technology of China Hefei China
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21
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Li S, Wu L, Zhang X, Jiang X. The Structure of Water Bonded to Phosphate Groups at the Electrified Zwitterionic Phospholipid Membranes/Aqueous Interface. Angew Chem Int Ed Engl 2020; 59:6627-6630. [DOI: 10.1002/anie.202000511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Shanshan Li
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Lie Wu
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
| | - Xiaofei Zhang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Xiue Jiang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
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22
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Li S, Wu L, Zhang X, Jiang X. The Structure of Water Bonded to Phosphate Groups at the Electrified Zwitterionic Phospholipid Membranes/Aqueous Interface. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Shanshan Li
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Lie Wu
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
| | - Xiaofei Zhang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Xiue Jiang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
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23
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Zhang Z, Hao C, Liu H, Zhang X, Sun R. Cholesterol mediates spontaneous insertion of Lycium barbarum polysaccharides in biomembrane model. ADSORPTION 2019. [DOI: 10.1007/s10450-019-00180-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Zander T, Wieland DCF, Raj A, Salmen P, Dogan S, Dėdinaitė A, Garamus VM, Schreyer A, Claesson PM, Willumeit-Römer R. Influence of high hydrostatic pressure on solid supported DPPC bilayers with hyaluronan in the presence of Ca 2+ ions. SOFT MATTER 2019; 15:7295-7304. [PMID: 31483431 DOI: 10.1039/c9sm01066a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The molecular mechanisms responsible for outstanding lubrication of natural systems, like articular joints, have been the focus of scientific research for several decades. One essential aspect is the lubrication under pressure, where it is important to understand how the lubricating entities adapt under dynamic working conditions in order to fulfill their function. We made a structural investigation of a model system consisting of two of the molecules present at the cartilage interface, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and hyaluronan, at high hydrostatic pressure. Phospholipid layers are found at the cartilage surfaces and are able to considerably reduce friction. Their behavior under load and varied solution conditions is important as pressures of 180 bar are encountered during daily life activities. We focus on how divalent ions, like Ca2+, affect the interaction between DPPC and hyaluronan, as other investigations have indicated that calcium ions influence their interaction. It could be shown that already low amounts of Ca2+ strongly influence the interaction of hyaluronan with DPPC. Our results suggest that the calcium ions increase the amount of adsorbed hyaluronan indicating an increased electrostatic interaction. Most importantly, we observe a modification of the DPPC phase diagram as hyaluronan absorbs to the bilayer which results in an Lα-like structure at low temperatures and a decoupling of the leaflets forming an asymmetric bilayer structure.
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Affiliation(s)
- Thomas Zander
- Helmholtz-Zentrum Geesthacht, Centre for Materials and Costal Research, Institute of Materials Research, Max-Planck-Straße 1, 21502 Geesthacht, Germany.
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25
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Okur HI, Tarun OB, Roke S. Chemistry of Lipid Membranes from Models to Living Systems: A Perspective of Hydration, Surface Potential, Curvature, Confinement and Heterogeneity. J Am Chem Soc 2019; 141:12168-12181. [DOI: 10.1021/jacs.9b02820] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Halil I. Okur
- Laboratory for Fundamental BioPhotonics
(LBP), Institute of Bioengineering (IBI) and Institute of Materials
Science (IMX), School of Engineering (STI) and Lausanne Center for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Orly B. Tarun
- Laboratory for Fundamental BioPhotonics
(LBP), Institute of Bioengineering (IBI) and Institute of Materials
Science (IMX), School of Engineering (STI) and Lausanne Center 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 Center for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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26
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Link KA, Spurzem GN, Tuladhar A, Chase Z, Wang Z, Wang H, Walker RA. Organic Enrichment at Aqueous Interfaces: Cooperative Adsorption of Glucuronic Acid to DPPC Monolayers Studied with Vibrational Sum Frequency Generation. J Phys Chem A 2019; 123:5621-5632. [DOI: 10.1021/acs.jpca.9b02255] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Katie A. Link
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Gabrielle N. Spurzem
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Aashish Tuladhar
- Physical Sciences Division, Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Zizwe Chase
- Department of Physics and Astronomy, Howard University, Washington, D.C. 20059, United States
| | - Zheming Wang
- Physical Sciences Division, Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Hongfei Wang
- Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200433, China
| | - Robert A. Walker
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
- Montana Materials Science Program, Montana State University, Bozeman, Montana 59717, United States
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27
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Chang H, Gnanasekaran K, Gianneschi NC, Geiger FM. Bacterial Model Membranes Deform (resp. Persist) upon Ni2+ Binding to Inner Core (resp. O-Antigen) of Lipopolysaccharides. J Phys Chem B 2019; 123:4258-4270. [DOI: 10.1021/acs.jpcb.9b02762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- HanByul Chang
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Karthikeyan Gnanasekaran
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Nathan C. Gianneschi
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Franz M. Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
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28
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Neal JF, Zhao W, Grooms AJ, Smeltzer MA, Shook BM, Flood AH, Allen HC. Interfacial Supramolecular Structures of Amphiphilic Receptors Drive Aqueous Phosphate Recognition. J Am Chem Soc 2019; 141:7876-7886. [DOI: 10.1021/jacs.9b02148] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jennifer F. Neal
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wei Zhao
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Alexander J. Grooms
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Morgan A. Smeltzer
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Brittany M. Shook
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Amar H. Flood
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Heather C. Allen
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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29
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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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30
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Zdrali E, Baer MD, Okur HI, Mundy CJ, Roke S. The Diverse Nature of Ion Speciation at the Nanoscale Hydrophobic/Water Interface. J Phys Chem B 2019; 123:2414-2423. [DOI: 10.1021/acs.jpcb.8b10207] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Evangelia Zdrali
- Laboratory for fundamental BioPhotonics, Institutes of Bioengineering and Materials Science and Engineering, School of Engineering, and Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Marcel D. Baer
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Halil I. Okur
- Laboratory for fundamental BioPhotonics, Institutes of Bioengineering and Materials Science and Engineering, School of Engineering, and Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Christopher J. Mundy
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Sylvie Roke
- Laboratory for fundamental BioPhotonics, Institutes of Bioengineering and Materials Science and Engineering, School of Engineering, and Lausanne Centre for Ultrafast Science, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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31
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Pullanchery S, Yang T, Cremer PS. Introduction of Positive Charges into Zwitterionic Phospholipid Monolayers Disrupts Water Structure Whereas Negative Charges Enhances It. J Phys Chem B 2018; 122:12260-12270. [DOI: 10.1021/acs.jpcb.8b08476] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Shi P, Zhang H, Lin L, Song C, Chen Q, Li Z. Molecular dynamics study of the effect of inorganic salts on the monolayer of four surfactants at the oil/water interface. J DISPER SCI TECHNOL 2018. [DOI: 10.1080/01932691.2018.1462200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Peng Shi
- Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, People's Republic of China
- College of Chemical Engineering, Harbin Institute of Petroleum, Harbin, People's Republic of China
| | - Hui Zhang
- Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, People's Republic of China
| | - Lin Lin
- Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, People's Republic of China
| | - Chunhui Song
- Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, People's Republic of China
| | - Qingguo Chen
- Key Laboratory of Engineering Dielectrics and Its Application of Ministry of Education & College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, People's Republic of China
| | - Zesheng Li
- Key Laboratory of Cluster Science of Ministry of Education & School of Chemistry, Beijing Institute of Technology, Beijing, People's Republic of China
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33
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Li S, Du L, Tsona NT, Wang W. The interaction of trace heavy metal with lipid monolayer in the sea surface microlayer. CHEMOSPHERE 2018; 196:323-330. [PMID: 29310068 DOI: 10.1016/j.chemosphere.2017.12.157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 12/17/2017] [Accepted: 12/22/2017] [Indexed: 06/07/2023]
Abstract
Lipid molecules and trace heavy metals are enriched in sea surface microlayer and can be transferred into the sea spray aerosol. To better understand their impact on marine aerosol generation and evolution, we investigated the interaction of trace heavy metals including Fe3+, Pb2+, Zn2+, Cu2+, Ni2+, Cr3+, Cd2+, and Co2+, with dipalmitoylphosphatidylcholine (DPPC) monolayers at the air-water interface. Phase behavior of the DPPC monolayer on heavy metal solutions was probed with surface pressure-area (π-A) isotherms. The conformation order and orientation of DPPC alkyl chains were characterized by infrared reflection-absorption spectroscopy (IRRAS). The π-A isotherms show that Zn2+ and Fe3+ strongly interact with DPPC molecules, and induce condensation of the monolayers in a concentration-dependent manner. IRRAS spectra show that the formation of cation-DPPC complex gives rise to conformational changes and immobilization of the headgroups. The current results suggest that the enrichment of Zn2+ in sea spray aerosols is due to strong binding to the DPPC film. The interaction of Fe3+ with DPPC monolayers can significantly influence their surface organizations through the formation of lipid-coated particles. These results suggest that the sea surface microlayer is capable of accumulating much higher amounts of these metals than the subsurface water. The organic and metal pollutants may transfer into the atmosphere by this interaction.
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Affiliation(s)
- Siyang Li
- Environment Research Institute, Shandong University, Shanda South Road 27, 250100 Shandong, China
| | - Lin Du
- Environment Research Institute, Shandong University, Shanda South Road 27, 250100 Shandong, China.
| | - Narcisse T Tsona
- Environment Research Institute, Shandong University, Shanda South Road 27, 250100 Shandong, China
| | - Wenxing Wang
- Environment Research Institute, Shandong University, Shanda South Road 27, 250100 Shandong, China
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34
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Li Y, Feng R, Lin L, Liu M, Guo Y, Zhang Z. Ordering effects of cholesterol on sphingomyelin monolayers investigated by high-resolution broadband sum-frequency generation vibrational spectroscopy. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2017.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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35
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Zhang J, Yang W, Tan J, Ye S. In situ examination of a charged amino acid-induced structural change in lipid bilayers by sum frequency generation vibrational spectroscopy. Phys Chem Chem Phys 2018; 20:5657-5665. [PMID: 29412195 DOI: 10.1039/c7cp07389e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The interactions between amino acids (AAs) and membranes represent various short-range and long-range interactions for biological phenomena; however, they are still poorly understood. In this study, we used cationic lysine and arginine as AA models, and systematically investigated the interactions between charged AAs and lipid bilayers using sum frequency generation vibrational spectroscopy (SFG-VS) in situ and in real time. The AA-induced dynamic structural changes of the lipid bilayer were experimentally monitored using the spectral features of CD2, CD3, the lipid head phosphate, and carbonyl groups in real time. Time-dependent SFG changes in the structure of the lipid bilayer provide direct evidence for the different interactions of lysine and arginine with the membrane. It was found that the discrepancy between lysine and arginine in binding with the lipid bilayer is due to the nature of the terminal functional groups. Arginine exhibits a more drastic impact on the membrane than lysine. SFG responses of the acyl chains, phosphate groups, and carbonyl groups provide evidence that the interaction between AAs and the membrane most likely follows an electrostatics and hydrogen bond-induced defect model. This work presents an exemplary method for comprehensive investigations of interactions between membranes and other functionally significant substances.
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Affiliation(s)
- Jiahui Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
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36
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Adams EM, Verreault D, Jayarathne T, Cochran RE, Stone EA, Allen HC. Surface organization of a DPPC monolayer on concentrated SrCl 2 and ZnCl 2 solutions. Phys Chem Chem Phys 2018; 18:32345-32357. [PMID: 27854367 DOI: 10.1039/c6cp06887a] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Transition metals are known to be enriched in organic-coated marine aerosols, but the impact these cations have on their surface properties is not well understood. Here the effect of Zn2+ enrichment on the surface properties of a dipalmitoylphosphatidylcholine (DPPC) monolayer was investigated and compared to that of the alkaline earth metal Sr2+, an ion not enriched in aerosols. Phase behavior of the DPPC film on concentrated aqueous solutions was probed with surface pressure-area isotherms while domain morphology was monitored with Brewster angle microscopy (BAM). Infrared reflection-absorption spectroscopy (IRRAS) and vibrational sum frequency generation (VSFG) spectroscopy were used to assess the impact of cations on the conformation and orientation of alkyl chains as well as the hydration state of the carbonyl and phosphatidylcholine (PC) moieties. Results of compression isotherms and BAM show that Zn2+ strongly interacts with DPPC molecules, and induces condensation of the monolayer while Sr2+ only weakly interacts with the monolayer in expanded phases. Conformational order and orientation of alkyl chains in the condensed phase are not significantly altered by either cation. IRRAS indicates that Sr2+ has weak interactions with the PC headgroup. Zn2+ ions cause dehydration of carbonyl groups and binds to the phosphate group in a 2 : 1 bridging complex. Findings here suggest that Sr2+ is not enriched in aerosols because it behaves similar to a monovalent ion and only weakly interacts with the monolayer, while enrichment of Zn2+ is due to strong binding to the lipid film.
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Affiliation(s)
- Ellen M Adams
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
| | - Dominique Verreault
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
| | | | - Richard E Cochran
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| | - Elizabeth A Stone
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, USA
| | - Heather C Allen
- Department of Chemistry & Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
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37
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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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38
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Wellen Rudd BA, Vidalis AS, Allen HC. Thermodynamic versus non-equilibrium stability of palmitic acid monolayers in calcium-enriched sea spray aerosol proxy systems. Phys Chem Chem Phys 2018; 20:16320-16332. [DOI: 10.1039/c8cp01188e] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Calcium ions bind to palmitic acid monolayers at the air–aqueous interface resulting in changes of both thermodynamic and non-equilibrium stability.
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Affiliation(s)
| | - Andrew S. Vidalis
- Department of Chemistry & Biochemistry
- The Ohio State University
- Columbus
- USA
| | - Heather C. Allen
- Department of Chemistry & Biochemistry
- The Ohio State University
- Columbus
- USA
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39
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Lee YK, Yu KJ, Kim Y, Yoon Y, Xie Z, Song E, Luan H, Feng X, Huang Y, Rogers JA. Kinetics and Chemistry of Hydrolysis of Ultrathin, Thermally Grown Layers of Silicon Oxide as Biofluid Barriers in Flexible Electronic Systems. ACS APPLIED MATERIALS & INTERFACES 2017; 9:42633-42638. [PMID: 29178781 PMCID: PMC6800003 DOI: 10.1021/acsami.7b15302] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Flexible electronic systems for bioimplants that offer long-term (multidecade) stability and safety in operation require thin, biocompatible layers that can prevent biofluid penetration. Recent work shows that ultrathin films of silicon dioxide thermally grown (TG-SiO2) on device-grade silicon wafers and then released as transferrable barriers offer a remarkable set of attributes in this context. This paper examines the chemical stability of these materials in aqueous solutions with different combinations of chemistries that are present in biofluids. Systematic measurements reveal the dependence of the dissolution rate of TG-SiO2 on concentrations of cations (Na+, K+, Mg2+, Ca2+) and anions (Cl-, HPO42-) at near-neutral pH. Certain results are consistent with previous studies on bulk samples of quartz and nanoparticles of amorphous silica; others reveal significant catalyzing effects associated with divalent cations at high pH and with specific anions at high ionic strength. In particular, Ca2+ and HPO42- greatly enhance and silicic acid greatly reduces the rates. These findings establish foundational data of relevance to predicting lifetimes of implantable devices that use TG-SiO2 as biofluid barriers, and of other classes of systems, such as environmental monitors, where encapsulation against water penetration is important.
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Affiliation(s)
- Yoon Kyeung Lee
- Department of Chemistry, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
| | - Ki Jun Yu
- Department of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Yerim Kim
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
| | - Younghee Yoon
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
| | - Zhaoqian Xie
- Department of Civil and Environmental Engineering, Mechanical Engineering, and Materials Science and Engineering, McCormick School of Engineering, and Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60208, United States
- AML, Department of Engineering Mechanics, Center for Mechanics and Materials, Tsinghua University, Beijing 100084, China
| | - Enming Song
- Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana–Champaign, Urbana, Illinois 61801, United States
- Department of Materials Science, Fudan University, Shanghai 200433, P.R. China
| | - Haiwen Luan
- Department of Civil and Environmental Engineering, Mechanical Engineering, and Materials Science and Engineering, McCormick School of Engineering, and Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60208, United States
| | - Xue Feng
- AML, Department of Engineering Mechanics, Center for Mechanics and Materials, Tsinghua University, Beijing 100084, China
| | - Yonggang Huang
- Department of Civil and Environmental Engineering, Mechanical Engineering, and Materials Science and Engineering, McCormick School of Engineering, and Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60208, United States
| | - John A. Rogers
- Center for Bio-Integrated Electronics, Departments of Materials Science and Engineering, Biomedical Engineering, Chemistry, Mechanical Engineering, Electrical Engineering and Computer Science, and Neurological Surgery, Simpson Querrey Institute for Nano/biotechnology, McCormick School of Engineering, and Feinberg School of Medicine, Northwestern University, Evanston, Illinois 60208, United States
- Corresponding Author
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40
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Martí J. Free-energy surfaces of ionic adsorption in cholesterol-free and cholesterol-rich phospholipid membranes. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2017.1391383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Jordi Martí
- Department of Physics, Technical University of Catalonia-Barcelona Tech, Barcelona, Spain
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41
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Feng RJ, Lin L, Li YY, Liu MH, Guo Y, Zhang Z. Effect of Ca 2+ to Sphingomyelin Investigated by Sum Frequency Generation Vibrational Spectroscopy. Biophys J 2017; 112:2173-2183. [PMID: 28538154 DOI: 10.1016/j.bpj.2017.04.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 04/06/2017] [Accepted: 04/17/2017] [Indexed: 10/19/2022] Open
Abstract
The interactions between Ca2+ ions and sphingomyelin play crucial roles in a wide range of cellular activities. However, little is known about the molecular details of the interactions at interfaces. In this work, we investigated the interactions between Ca2+ ions and egg sphingomyelin (ESM) Langmuir monolayers at the air/water interface by subwavenumber high-resolution broadband sum frequency generation vibrational spectroscopy (HR-BB-SFG-VS). We show that Ca2+ ions can induce ordering of the acyl chains in the ESM monolayer. An analysis of the one alkyl-chain-deuterated ESM revealed that the Ca2+ ions do not affect the N-linked saturated fatty acid chain, although they make the sphingosine backbone become ordered. Further analysis of the SFG-VS spectra shows that the interactions between ESM and Ca2+ ions make the orientation of the methyl group at the end of sphingosine backbone change from pointing downward to pointing upward. Moreover, a large blue shift of the phosphate group at the CaCl2 solution interface indicates, to our knowledge, new cation binding modes. Such binding causes the phosphate moiety to dehydrate, resulting in the conformation change of the phosphate moiety. Based on these results, we propose the molecular mechanism that Ca2+ ions can bind to the phosphate group and subsequently destroy the intramolecular hydrogen bond between the 3-hydroxyl group and the phosphate oxygen, which results in an ordering change of the sphingosine backbone. These findings illustrate the potential application of HR-BB-SFG-VS to investigate lipid-cation interactions and the calcium channel modulated by lipid domain formation through slight structural changes in the membrane lipid. It will also shed light on the interactions of complex molecules at surfaces and interfaces.
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Affiliation(s)
- Rong-Juan Feng
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Lu Lin
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; National Center for Nanoscience and Technology, Beijing, China
| | - Yi-Yi Li
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Ming-Hua Liu
- National Center for Nanoscience and Technology, Beijing, China; Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | - Yuan Guo
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
| | - Zhen Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.
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42
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Okur HI, Chen Y, Smolentsev N, Zdrali E, Roke S. Interfacial Structure and Hydration of 3D Lipid Monolayers in Aqueous Solution. J Phys Chem B 2017; 121:2808-2813. [DOI: 10.1021/acs.jpcb.7b00609] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- 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
| | - 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
| | - Nikolay Smolentsev
- 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
| | - Evangelia Zdrali
- 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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43
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Bilkova E, Pleskot R, Rissanen S, Sun S, Czogalla A, Cwiklik L, Róg T, Vattulainen I, Cremer PS, Jungwirth P, Coskun Ü. Calcium Directly Regulates Phosphatidylinositol 4,5-Bisphosphate Headgroup Conformation and Recognition. J Am Chem Soc 2017; 139:4019-4024. [PMID: 28177616 PMCID: PMC5364432 DOI: 10.1021/jacs.6b11760] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The orchestrated recognition of phosphoinositides and concomitant intracellular release of Ca2+ is pivotal to almost every aspect of cellular processes, including membrane homeostasis, cell division and growth, vesicle trafficking, as well as secretion. Although Ca2+ is known to directly impact phosphoinositide clustering, little is known about the molecular basis for this or its significance in cellular signaling. Here, we study the direct interaction of Ca2+ with phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), the main lipid marker of the plasma membrane. Electrokinetic potential measurements of PI(4,5)P2 containing liposomes reveal that Ca2+ as well as Mg2+ reduce the zeta potential of liposomes to nearly background levels of pure phosphatidylcholine membranes. Strikingly, lipid recognition by the default PI(4,5)P2 lipid sensor, phospholipase C delta 1 pleckstrin homology domain (PLC δ1-PH), is completely inhibited in the presence of Ca2+, while Mg2+ has no effect with 100 nm liposomes and modest effect with giant unilamellar vesicles. Consistent with biochemical data, vibrational sum frequency spectroscopy and atomistic molecular dynamics simulations reveal how Ca2+ binding to the PI(4,5)P2 headgroup and carbonyl regions leads to confined lipid headgroup tilting and conformational rearrangements. We rationalize these findings by the ability of calcium to block a highly specific interaction between PLC δ1-PH and PI(4,5)P2, encoded within the conformational properties of the lipid itself. Our studies demonstrate the possibility that switchable phosphoinositide conformational states can serve as lipid recognition and controlled cell signaling mechanisms.
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Affiliation(s)
- Eva Bilkova
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,German Center for Diabetes Research (DZD e.V.) , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Roman Pleskot
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,Institute of Experimental Botany, Academy of Sciences of the Czech Republic , v.v.i., Rozvojová 263, 16502 Prague 6, Czech Republic
| | - Sami Rissanen
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland
| | | | - Aleksander Czogalla
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,Laboratory of Cytobiochemistry, Faculty of Biotechnology, University of Wrocław , Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Lukasz Cwiklik
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic , v.v.i., Dolejskova 3, 18223 Prague 8, Czech Republic
| | - Tomasz Róg
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland.,Department of Physics, University of Helsinki , P.O. Box 64, FI-00014, Helsinki, Finland
| | - Ilpo Vattulainen
- Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland.,Department of Physics, University of Helsinki , P.O. Box 64, FI-00014, Helsinki, Finland.,MEMPHYS- Center for Biomembrane Physics, University of Southern Denmark , DK-5230 Odense, Denmark
| | | | - Pavel Jungwirth
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic , Flemingovo náměstí 2, 16610 Prague 6, Czech Republic.,Department of Physics, Tampere University of Technology , P.O. Box 692, FI-33101 Tampere, Finland
| | - Ünal Coskun
- Paul Langerhans Institute Dresden of the Helmholtz Zentrum München at the University Hospital and Faculty of Medicine Carl Gustav Carus of TU Dresden, Technische Universität Dresden , Fetscher Strasse 74, 01307 Dresden, Germany.,German Center for Diabetes Research (DZD e.V.) , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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44
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Feng RJ, Li X, Zhang Z, Lu Z, Guo Y. Spectral assignment and orientational analysis in a vibrational sum frequency generation study of DPPC monolayers at the air/water interface. J Chem Phys 2016; 145:244707. [DOI: 10.1063/1.4972564] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Rong-Juan Feng
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xia Li
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhen Zhang
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhou Lu
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Yuan Guo
- Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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45
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Zhang T, Cathcart MG, Vidalis AS, Allen HC. Cation effects on phosphatidic acid monolayers at various pH conditions. Chem Phys Lipids 2016; 200:24-31. [DOI: 10.1016/j.chemphyslip.2016.06.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 05/11/2016] [Accepted: 06/01/2016] [Indexed: 11/29/2022]
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46
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Adams EM, Casper CB, Allen HC. Effect of cation enrichment on dipalmitoylphosphatidylcholine (DPPC) monolayers at the air-water interface. J Colloid Interface Sci 2016; 478:353-64. [DOI: 10.1016/j.jcis.2016.06.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/02/2016] [Accepted: 06/03/2016] [Indexed: 01/07/2023]
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47
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van der Vegt NFA, Haldrup K, Roke S, Zheng J, Lund M, Bakker HJ. Water-Mediated Ion Pairing: Occurrence and Relevance. Chem Rev 2016; 116:7626-41. [DOI: 10.1021/acs.chemrev.5b00742] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nico F. A. van der Vegt
- Eduard-Zintl-Institut
für Anorganische und Physikalische Chemie and Center of Smart
Interfaces, Technische Universität Darmstadt, Alarich-Weiss-Strasse
10, 64287 Darmstadt, Germany
| | - Kristoffer Haldrup
- Physics
Department, NEXMAP Section, Technical University of Denmark, Fysikvej
307, 2800 Kongens
Lyngby, Denmark
| | - Sylvie Roke
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering, and Institute
of Materials Science, School of Engineering, and Lausanne Centre for
Ultrafast Science, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Junrong Zheng
- College
of Chemistry and Molecular Engineering, Beijing National Laboratory
for Molecular Sciences, Peking University, Beijing 100871, China
- Department
of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005-1892, United States
| | - Mikael Lund
- Division
of Theoretical Chemistry, Department of Chemistry, Lund University, SE-22100 Lund, Sweden
| | - Huib J. Bakker
- FOM Institute AMOLF, Science
Park 104, 1098 XG Amsterdam, The Netherlands
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48
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Smolentsev N, Lütgebaucks C, Okur HI, de Beer AGF, Roke S. Intermolecular Headgroup Interaction and Hydration as Driving Forces for Lipid Transmembrane Asymmetry. J Am Chem Soc 2016; 138:4053-60. [DOI: 10.1021/jacs.5b11776] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Nikolay Smolentsev
- 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
| | - 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
| | - Alex G. F. de Beer
- 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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49
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Casper CB, Verreault D, Adams EM, Hua W, Allen HC. Surface Potential of DPPC Monolayers on Concentrated Aqueous Salt Solutions. J Phys Chem B 2016; 120:2043-52. [PMID: 26761608 DOI: 10.1021/acs.jpcb.5b10483] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Clayton B. Casper
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Dominique Verreault
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Ellen M. Adams
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Wei Hua
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Heather C. Allen
- Department of Chemistry and
Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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50
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Yang J, Bonomi M, Calero C, Martí J. Free energy landscapes of sodium ions bound to DMPC–cholesterol membrane surfaces at infinite dilution. Phys Chem Chem Phys 2016; 18:9036-41. [DOI: 10.1039/c5cp05527j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Typical configuration of two DMPC lipids and one cholesterol molecule solvating one sodium ion, together with two additional water molecules.
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Affiliation(s)
- Jing Yang
- Department of Physics
- Technical University of Catalonia-Barcelona Tech
- 08034 Barcelona
- Spain
| | | | - Carles Calero
- Center for Polymer Studies and Department of Physics
- Boston University
- Boston
- USA
| | - Jordi Martí
- Department of Physics
- Technical University of Catalonia-Barcelona Tech
- 08034 Barcelona
- Spain
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