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Cecchet F. Light on the interactions between nanoparticles and lipid membranes by interface-sensitive vibrational spectroscopy. Colloids Surf B Biointerfaces 2024; 241:114013. [PMID: 38865867 DOI: 10.1016/j.colsurfb.2024.114013] [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: 02/27/2024] [Revised: 05/10/2024] [Accepted: 06/03/2024] [Indexed: 06/14/2024]
Abstract
Nanoparticles are produced in natural phenomena or synthesized artificially for technological applications. Their frequent contact with humans has been judged potentially harmful for health, and numerous studies are ongoing to understand the mechanisms of the toxicity of nanoparticles. At the macroscopic level, the toxicity can be established in vitro or in vivo by measuring the survival of cells. At the sub-microscopic level, scientists want to unveil the molecular mechanisms of the first interactions of nanoparticles with cells via the cell membrane, before the toxicity cascades within the whole cell. Unveiling a molecular understanding of the nanoparticle-membrane interface is a tricky challenge, because of the chemical complexity of this system and its nanosized dimensions buried within bulk macroscopic environments. In this review, we highlight how, in the last 10 years, second-order nonlinear optical (NLO) spectroscopy, and specifically vibrational sum frequency generation (SFG), has provided a new understanding of the structural, physicochemical, and dynamic properties of these biological interfaces, with molecular sensitivity. We will show how the intrinsic interfacial sensitivity of second-order NLO and the chemical information of vibrational SFG spectroscopy have revealed new knowledge of the molecular mechanisms that drive nanoparticles to interact with cell membranes, from both sides, the nanoparticles and the membrane properties.
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Affiliation(s)
- Francesca Cecchet
- Laboratory of Lasers and Spectroscopies (LLS), Namur Institute of Structured Matter (NISM) and NAmur Institute for Life Sciences (NARILIS), University of Namur (UNamur), Belgium.
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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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Shaikh N, Bernhard SP, Walker RA. Surface Activity and Aggregation Behavior of Polyhydroxylated Fullerenes in Aqueous Solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10412-10418. [PMID: 35969487 DOI: 10.1021/acs.langmuir.2c01052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Polyhydroxylated fullerene (PHF) surface activity and aggregation behavior at the air-water interface were examined using surface tension and resonance-enhanced second harmonic generation (SHG). Surface tension data showed that PHFs are surface active with a limiting surface excess corresponding to 130 Å2/molecule in aqueous (Millipore water) solutions. Increasing the solution-phase ionic strength (through the addition of NaCl) reduces the PHF surface excess. Conductivity measurements show that PHFs carry a single charge, presumably negative. Surface-specific SHG experiments show a small but measurable fixed wavelength, nonlinear response from solutions having surface excess coverages as low as ∼400 Å2/molecule. The SHG response of PHF solutions in the low-concentration limit shows unexpected behavior, implying that at bulk concentrations below 0.06 mg/mL, PHF monomers adsorb to the surface and interfere destructively with the intrinsic nonlinear susceptibility of the aqueous/vapor interface, leading to a ∼75% reduction in the SH signal. Above a PHF concentration of 0.0.06 mg/mL, the SH signal begins to rise in the Millipore and 50 mM NaCl solutions but remains very low in the 500 mM NaCl solutions. From this behavior, we infer that an increased nonlinear optical response is due to adsorbed aggregates.
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Affiliation(s)
- Nida Shaikh
- Chemistry and Biochemistry Department, Montana State University, Bozeman, Montana 59717, United States
| | - Samuel P Bernhard
- Chemistry and Biochemistry Department, Montana State University, Bozeman, Montana 59717, United States
| | - Robert A Walker
- Chemistry and Biochemistry Department, Montana State University, Bozeman, Montana 59717, United States
- Montana Materials Science Program, Montana State University, Bozeman, Montana 59717, United States
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4
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Shiu RF, Chen LY, Lee HJ, Gong GC, Lee C. New insights into the role of marine plastic-gels in microplastic transfer from water to the atmosphere via bubble bursting. WATER RESEARCH 2022; 222:118856. [PMID: 35863277 DOI: 10.1016/j.watres.2022.118856] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
The pervasiveness of microplastics (MPs) in global oceans is raising concerns about their adverse impacts on ecosystems. The mechanistic understanding of MP transport is critical for evaluating its fate, flux, and ecological risks specifically. Currently, bubble bursting is believed to represent an important route for MP transfer from sea surfaces to the atmosphere. However, the detailed mechanisms of the complex physico-chemical interactions between MPs, water composition, and gel particles in the air-sea interface remain unknown. Our results suggested three steps for MP transfer between air-sea phases: (1) MPs incorporating into gel aggregates in the water column; (2) further accumulation of plastic-gel aggregate in the surface layer phase; finally (3) ejection of aggregates from the sea when bubbles of trapped air rise to the surface and burst. The water composition (e.g., high salinity, gel concentration and viscosity) can modulate plastic-gel aggregation and subsequent transport from water to the atmosphere. The possible mechanism may be closely tied to the formation of plastic-gel via cation-linking bridges, thereby enhancing plastic-gel ejection into air. Collectively, this work offers unique insights into the role of marine plastic-gels in determining MP fate and transport, especially at air-sea interfaces. The data also provide a better understanding of the corresponding mechanism that may explain the fates of missing plastics in the ocean.
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Affiliation(s)
- Ruei-Feng Shiu
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung City 202301, Taiwan; Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung City 202301, Taiwan.
| | - Lu-Yi Chen
- Department of Microbiology, Immunology and Biopharmaceuticals, National Chiayi University, Chiayi City 60004, Taiwan
| | - Hui-Ju Lee
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung City 202301, Taiwan
| | - Gwo-Ching Gong
- Institute of Marine Environment and Ecology, National Taiwan Ocean University, Keelung City 202301, Taiwan; Center of Excellence for the Oceans, National Taiwan Ocean University, Keelung City 202301, Taiwan
| | - Chuping Lee
- Department of Chemistry, Fu Jen Catholic University, New Taipei City 24205, Taiwan.
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5
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Shaikh N, Andriolo JM, Skinner JL, Walker RA. Carbon Nanoparticle-Induced Changes to Lipid Monolayer Structure at Water-Air Interfaces. J Phys Chem B 2022; 126:5667-5677. [PMID: 35877465 DOI: 10.1021/acs.jpcb.2c02526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Surface specific vibrational spectroscopy experiments together with surface tension measurements and spectroscopic ellipsometry data were used to characterize the effects of soluble carbon particulates on compressed and partially compressed lipid monolayers adsorbed to the water-air interface. The lipid monolayers consisted of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DPPC), and measurements were made for both tightly packed monolayers (40 Å2/molecule) and monolayers in their liquid condensed state (55 Å2/molecule). Langmuir trough data show that very small amounts of PHF (0.0075 mg/mL or 6.4 × 10-6 M) decrease lipid film compressibility. This finding supports a cooperative adsorption mechanism whereby the soluble PHFs are drawn to the surface and associate with the insoluble DPPC monolayer. Excess free energies (ΔGmixE) were positive, consistent with the cooperative adsorption mechanism, and although the excess free energies are small (≤1 kJ/mol), adsorbed PHF has measurable effects on monolayer structure. Further support for the cooperative adsorption mechanism at the water-air interface comes from vibrational sum frequency generation (VSFG) experiments. Low PHF concentrations (≤0.06 mg/mL) increase DPPC acyl chain ordering in liquid condensed lipid films and decrease DPPC acyl chain ordering and film thickness in tightly packed lipid films.
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Affiliation(s)
- Nida Shaikh
- Chemistry and Biochemistry Department, Montana State University, Bozeman, Montana 59717, United States
| | - Jessica M Andriolo
- Mechanical Engineering Department, Montana Technological University, Butte, Montana U.S. 59701, United States.,Montana Tech Nanotechnology Laboratory, Montana Technological University, Butte, Montana 59701, United States
| | - Jack L Skinner
- Mechanical Engineering Department, Montana Technological University, Butte, Montana U.S. 59701, United States.,Montana Tech Nanotechnology Laboratory, Montana Technological University, Butte, Montana 59701, United States.,Materials Science Ph.D. Program, Montana Technological University, Butte, Montana 59701, United States
| | - Robert A Walker
- Chemistry and Biochemistry Department, Montana State University, Bozeman, Montana 59717, United States.,Montana Materials Science Program, Montana State University, Bozeman, Montana 59717, United States
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6
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Yiyen G, Duck KV, Walker RA. Surfactant Adsorption to Gypsum Surfaces and the Effects on Solubility in Aqueous Solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2804-2810. [PMID: 35220715 DOI: 10.1021/acs.langmuir.1c02890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Vibrational sum frequency generation (VSFG) spectroscopy, conductometric titration measurements, and EDX elemental mapping were used to examine surfactant adsorption to the gypsum (010) surface and assess the effects of surfactant adsorption on gypsum solubility in aqueous solutions. Sodium dodecyl sulfate (SDS) and dodecyltrimethylammonium chloride (DTAC) were used as anionic and cationic surfactants, respectively. Gypsum/SDS interactions result in an ordered precipitate layer on the gypsum surface after water evaporation; gypsum/DTAC interaction did not show a similar effect, despite exposure of gypsum to equivalent amounts of surfactant. VSFG spectra showed that SDS molecules adsorb with their chains parallel to the gypsum surface; spectra from gypsum surfaces treated with DTAC, however, showed no measurable response, implying that these surfactants form disorganized aggregates with no polar ordering. Vibrational data were supported by independent EDX measurements that show a uniform distribution of SDS across the gypsum surface. In contrast, element-specific EDX images showed that DTAC clustered in tightly localized patches that left most of the gypsum surface exposed. The uniform adsorption of SDS on the gypsum surface suppresses long-term dissolution up to 40% when compared to samples exposed to DTAC. Gypsum samples in DTAC-containing solutions lose approximately the same amount of material to dissolution as samples immersed in pure water.
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7
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Analytical challenges of glycosaminoglycans at biological interfaces. Anal Bioanal Chem 2021; 414:85-93. [PMID: 34647134 PMCID: PMC8514262 DOI: 10.1007/s00216-021-03705-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 11/15/2022]
Abstract
The analysis of glycosaminoglycans (GAGs) is a challenging task due to their high structural heterogeneity, which results in diverse GAG chains with similar chemical properties. Simultaneously, it is of high importance to understand their role and behavior in biological systems. It has been known for decades now that GAGs can interact with lipid molecules and thus contribute to the onset of atherosclerosis, but their interactions at and with biological interfaces, such as the cell membrane, are yet to be revealed. Here, analytical approaches that could yield important knowledge on the GAG-cell membrane interactions as well as the synthetic and analytical advances that make their study possible are discussed. Due to recent developments in laser technology, we particularly focus on nonlinear spectroscopic methods, especially vibrational sum-frequency generation spectroscopy, which has the potential to unravel the structural complexity of heterogeneous biological interfaces in contact with GAGs, in situ and in real time.
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Carter-Fenk KA, Dommer AC, Fiamingo ME, Kim J, Amaro RE, Allen HC. Calcium bridging drives polysaccharide co-adsorption to a proxy sea surface microlayer. Phys Chem Chem Phys 2021; 23:16401-16416. [PMID: 34318808 DOI: 10.1039/d1cp01407b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Saccharides comprise a significant mass fraction of organic carbon in sea spray aerosol (SSA), but the mechanisms through which saccharides are transferred from seawater to the ocean surface and eventually into SSA are unclear. It is hypothesized that saccharides cooperatively adsorb to other insoluble organic matter at the air/sea interface, known as the sea surface microlayer (SSML). Using a combination of surface-sensitive infrared reflection-absorption spectroscopy and all-atom molecular dynamics simulations, we demonstrate that the marine-relevant, anionic polysaccharide alginate co-adsorbs to an insoluble palmitic acid monolayer via divalent cationic bridging interactions. Ca2+ induces the greatest extent of alginate co-adsorption to the monolayer, evidenced by the ∼30% increase in surface coverage, whereas Mg2+ only facilitates one-third the extent of co-adsorption at seawater-relevant cation concentrations due to its strong hydration propensity. Na+ cations alone do not facilitate alginate co-adsorption, and palmitic acid protonation hinders the formation of divalent cationic bridges between the palmitate and alginate carboxylate moieties. Alginate co-adsorption is largely confined to the interfacial region beneath the monolayer headgroups, so surface pressure, and thus monolayer surface coverage, only changes the amount of alginate co-adsorption by less than 5%. Our results provide physical and molecular characterization of a potentially significant polysaccharide enrichment mechanism within the SSML.
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Affiliation(s)
- Kimberly A Carter-Fenk
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
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Wang Z, Walter ED, Sassi M, Zhang X, Zhang H, Li XS, Chen Y, Cui W, Tuladhar A, Chase Z, Winkelman AD, Wang HF, Pearce CI, Clark SB, Rosso KM. The role of surface hydroxyls on the radiolysis of gibbsite and boehmite nanoplatelets. JOURNAL OF HAZARDOUS MATERIALS 2020; 398:122853. [PMID: 32768813 DOI: 10.1016/j.jhazmat.2020.122853] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
Understanding mechanistic pathways to radiolytic hydrogen generation by metal oxyhydroxide nanomaterials is challenging because of the difficulties of distinguishing key locations of OH bond scission, from structural interiors to hydroxylated surfaces to physi-sorbed water molecules. Here we exploited the interface-selectivity of vibrational sum frequency generation (VSFG) to isolate surface versus bulk hydroxyl groups for gibbsite and boehmite nanoplatelets before and after 60Co irradiation at dose levels of approximately 7.0 and 29.6 Mrad. While high-resolution microscopy revealed no effect on particle bulk and surface structures, VSFG results clearly indicated up to 83% and 94% radiation-induced surface OH bond scission for gibbsite and boehmite, respectively, a substantially higher proportion than observed for interior OH groups by IR and Raman spectroscopy. Electron paramagnetic spectroscopy revealed that the major radiolysis products bound in the mineral structures are trapped electrons, O, O2- and possibly F-centers in gibbsite, and H, O and O3- in boehmite, which persist on the time frame of several months. The entrapped radiolysis products appear to be highly stable, enduring re-hydration of particle surfaces, and likely reflect a permanent adjustment in the thermodynamic stabilities of these nanomaterials.
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Affiliation(s)
- Zheming Wang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States.
| | - Eric D Walter
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Michel Sassi
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Xin Zhang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Hailin Zhang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Xiaohong S Li
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Ying Chen
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Wenwen Cui
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Aashish Tuladhar
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Zizwe Chase
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Austin D Winkelman
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, China
| | | | - Carolyn I Pearce
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
| | - Sue B Clark
- Energy and Environmental Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States; Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Kevin M Rosso
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, United States
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Link KA, Spurzem GN, Tuladhar A, Chase Z, Wang Z, Wang H, Walker RA. Cooperative Adsorption of Trehalose to DPPC Monolayers at the Water–Air Interface Studied with Vibrational Sum Frequency Generation. J Phys Chem B 2019; 123:8931-8938. [DOI: 10.1021/acs.jpcb.9b07770] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - 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
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11
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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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