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Mapile AN, LeRoy MA, Fabrizio K, Scatena LF, Brozek CK. The Surface of Colloidal Metal-Organic Framework Nanoparticles Revealed by Vibrational Sum Frequency Scattering Spectroscopy. ACS NANO 2024; 18:13406-13414. [PMID: 38722052 DOI: 10.1021/acsnano.4c03758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Solvation shells strongly influence the interfacial chemistry of colloidal systems, from the activity of proteins to the colloidal stability and catalysis of nanoparticles. Despite their fundamental and practical importance, solvation shells have remained largely undetected by spectroscopy. Furthermore, their ability to assemble at complex but realistic interfaces with heterogeneous and rough surfaces remains an open question. Here, we apply vibrational sum frequency scattering spectroscopy (VSFSS), an interface-specific technique, to colloidal nanocrystals with porous metal-organic frameworks (MOFs) as a case study. Due to the porous nature of the solvent-particle boundary, MOF particles challenge conventional models of colloidal and interfacial chemistry. Their multiweek colloidal stability in the absence of conventional surface ligands suggests that stability may arise in part from solvation forces. Spectra of colloidally stable Zn(2-methylimidazolate)2 (ZIF-8) in polar solvents indicate the presence of ordered solvation shells, solvent-metal binding, and spontaneous ordering of organic bridging linkers within the MOF. These findings help explain the unexpected colloidal stability of MOF colloids, while providing a roadmap for applying VSFSS to wide-ranging colloidal nanocrystals in general.
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Affiliation(s)
- Ashley N Mapile
- Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Michael A LeRoy
- Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Kevin Fabrizio
- Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Lawrence F Scatena
- Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Carl K Brozek
- Department of Chemistry and Biochemistry, Materials Science Institute, University of Oregon, Eugene, Oregon 97403, United States
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2
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Sara RJ, Coers D, Behrman C, Bobay J, Subir M. Molecular Adsorption and Physicochemical Properties at Liquid/Liquid Nanoemulsion Soft Interfaces: Effect of Charge and Hydrophobicity. J Phys Chem B 2024. [PMID: 38498699 DOI: 10.1021/acs.jpcb.3c07907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Contrary to the popular adage, "Oil and water do not mix", evidence of mixtures comprising the two "immiscible" liquids is universal. In the presence of an emulsifier, oil and water mix to form a colloidal suspension known as emulsion. Their utility in many areas such as food chemistry, biomedical health sectors, catalysis, and the petroleum industry is well recognized. While their application in our society is pervasive, tantalizing fundamental questions regarding the chemistry that takes place at the oil/water soft interface still linger. For instance, do organic compounds show proclivity for this molecularly thin boundary and, if so, what forces, hydrophobic or pure electrostatic among others, drive the molecular interactions? The focus of this Article is on molecular adsorption at the interface of oil-in-water (O/W) nanoemulsion (NE) droplets. The effect of the interfacial surfactant charge (positive, negative, zwitterionic, and neutral) on the affinity of aromatic organic compounds on the O/W NEs has been studied. Using a second harmonic generation (SHG), a nonlinear light scattering technique, we have explored the adsorption equilibrium of charged and neutral organic dyes. By variation of the surfactant functional group and thereby the interfacial charge properties, the source of the adsorption interaction, if any, has been deduced. The population of surfactants containing a charged functional group at the O/W interface is found to be sparse, yet adsorption at some of these interfaces has been observed. A purely electrostatic Coulomb interaction plays a key role, but the presence of a charged interface does not necessitate molecular adsorption. Hydrophobic interactions are not a major driving force of adsorption for the SHG dyes studied. However, a possible pi-interaction is likely in explaining the accumulation of neutral aromatic compounds at the O/W NE interface. These intricate adsorption features are discussed in the context of NE interfacial charge properties and their stability upon molecular adsorption.
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Affiliation(s)
- Rubyat J Sara
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Derek Coers
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Charles Behrman
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Jaron Bobay
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
| | - Mahamud Subir
- Department of Chemistry, Ball State University, Muncie, Indiana 47306, United States
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3
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Changez M, Anwar MF, Alrahbi H. Olive Oil-Based Reverse Microemulsion for Stability and Topical Delivery of Methotrexate: In Vitro. ACS OMEGA 2024; 9:7012-7021. [PMID: 38371785 PMCID: PMC10870400 DOI: 10.1021/acsomega.3c08875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/18/2023] [Accepted: 01/17/2024] [Indexed: 02/20/2024]
Abstract
Hydrolysis of pharmaceutically active molecules can be in control under a confined environment of water-in-oil microemulsion. Stability of model drug methotrexate (MTX) in a sodium bis(2-ethylhexyl) sulfosuccinate (AOT) and olive oil microemulsion system has been evaluated. The physicochemical properties of AOT-MTX-water-olive oil reverse microemulsion (MTX-RM) were examined by UV-vis, Fourier transform infrared, and X-ray diffraction techniques, and the hydrodynamic size was determined by dynamic light scattering techniques and morphologies were characterized by a transmission electron microscope and atomic force microscope. In vitro permeation of MTX-RM through treated skin and its mechanism are evaluated by a UV-visible spectrophotometer, confocal laser scanning microscope, differential scanning calorimeter, and attenuated total reflecting infrared spectroscopy (ATR). The interaction of MTX with the AOT headgroup in confined environment RM enhanced the stability of MTX without affecting the molecular integrity at room temperature. Chemical stability of MTX in MTX-RM (W0 = 5) is significantly higher (∼97%) at room temperature for the study period of 1 year than in MTX-RM (W0 = 15) (∼72%). Interaction of MTX with the AOT headgroup is also visualized by a high-resolution transmission electron microscope and is in correlation with FT-IR data of MTX-RM. The skin fluxes of MTX are 15.1, 19.75, and 22.75 times higher at water content (W0) of 5, 10, and 15, respectively, in MTX-RM in comparison to aqueous solution of MTX. The enhanced amounts of the MTX were detected using CLSM in hair follicles, sweat glands, and epidermis layer of the skin. Merging of T2, T3, and T4 thermal peaks in one broad peak in treated skin endothermograph shows that carrier MTX-RM affects the lipid as well protein structure of the treated skin. ATR data of treated skin showed an increase in the intensity of the carbonyl peak at 1750 cm-1 (lipid), shifting of the amide II peaks, and separation of peaks in the range of 1060 to 1000 cm-1 (vibration mode of -CH2OH, C-O stretching, and C-OH bending peak of the carbohydrate) in comparison to control skin, which indicates that MTX-RM interacts with glycolipid and glycoprotein through carbohydrate hydroxy groups.
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Affiliation(s)
- Mohammad Changez
- College
of Health Science, University of Buraimi, Al Buraimi 512, Oman
| | - Mohammad Faiyaz Anwar
- Department
of Microbiology, All Indian Institute of
Medical Sciences AIIMS, New Delhi 110608, India
| | - Hilal Alrahbi
- College
of Health Science, University of Buraimi, Al Buraimi 512, Oman
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4
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Hammond OS, Elstone NS, Doutch J, Li P, Edler KJ. Evidence for an L 3 phase in ternary deep eutectics: composition-induced L 3-to-L α transition of AOT. NANOSCALE 2023; 15:19314-19321. [PMID: 37997686 DOI: 10.1039/d3nr03689h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
Pure and hydrated deep eutectic solvents (DES) are proposed to form self-assembled nanostructures within the fluid bulk, similar to the bicontinuous L3 phase common for ionic liquids (ILs). Labelled choline chloride : urea : water DES were measured using small-angle neutron scattering (SANS), showing no long-range nanostructure. However, solutions of the surfactant AOT in this DES yielded scattering consistent with the L3 "sponge" phase, which was fitted using the Teubner-Strey model. A disclike model gave local structural information, namely, a linear increase in radius versus solvent water content (w = molar ratio of DES : water), eventually forming large, turbid lamellar phases at 10w; an L3-to-Lα transition was observed. Simultaneous multi-contrast SANS fits show the surfactant headgroup region is dominated by interactions with poorly-soluble Na+ at low water contents, and numerically-superior [cholinium]+ as water content increases. The modified interfacial Gaussian curvature from cation : anion volume matching stabilizes the lamellar morphology, allowing the bilayer aggregation number to increase.
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Affiliation(s)
- Oliver S Hammond
- Centre for Sustainable Chemical Technologies & Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Naomi S Elstone
- Centre for Sustainable Chemical Technologies & Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - James Doutch
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford OX11 0QX, UK
| | - Peixun Li
- ISIS Neutron & Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell-Oxford OX11 0QX, UK
| | - Karen J Edler
- Centre for Sustainable Chemical Technologies & Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund 221 00, Sweden
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5
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Gu P, Luo X, Zhou S, Wang D, Li Z, Chai Y, Zhang Y, Shi S, Russell TP. Stabilizing Liquids Using Interfacial Supramolecular Assemblies. Angew Chem Int Ed Engl 2023; 62:e202303789. [PMID: 37198522 DOI: 10.1002/anie.202303789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 05/17/2023] [Accepted: 05/17/2023] [Indexed: 05/19/2023]
Abstract
Stabilizing liquids based on supramolecular assembly (non-covalent intermolecular interactions) has attracted significant interest, due to the increasing demand for soft, liquid-based devices where the shape of the liquid is far from the equilibrium spherical shape. The components comprising these interfacial assemblies must have sufficient binding energies to the interface to prevent their ejection from the interface when the assemblies are compressed. Here, we highlight recent advances in structuring liquids based on non-covalent intermolecular interactions. We describe some of the progress made that reveals structure-property relationships. In addition to treating advances, we discuss some of the limitations and provide a perspective on future directions to inspire further studies on structured liquids based on supramolecular assembly.
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Affiliation(s)
- Peiyang Gu
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Xiaobo Luo
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Shiyuan Zhou
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Danfeng Wang
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Zhongyu Li
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Yu Chai
- Department of Physics, City University of Hong Kong, Kowloon, P. R. China
| | - Yuzhe Zhang
- School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Shaowei Shi
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Thomas P Russell
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
- Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA 01003, USA
- Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba, Sendai, 980-8577, Japan
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6
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Carpenter AP, Golbek TW. "Nonlinear" pursuit of understanding pollutant accumulation and chemistry at environmental and biological interfaces. Biointerphases 2023; 18:058501. [PMID: 37728303 DOI: 10.1116/6.0003059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 08/25/2023] [Indexed: 09/21/2023] Open
Abstract
Over the past few decades, the public recognition of the prevalence of certain classes of pollutants, such as perfluoroalkyl substances and nanoplastics, within the environment, has sparked growing concerns over their potential impact on environmental and human health. Within both environmental and biological systems, the adsorption and structural organization of pollutants at aqueous interfaces can greatly impact the chemical reactivity and transformation. Experimentally probing chemical behavior at interfaces can often pose a problem due to bulk solvated molecules convoluting molecular signatures from interfacial molecules. To solve this problem, there exist interface-specific nonlinear spectroscopy techniques that can directly probe both macroscopic planar interfaces and nanoplastic interfaces in aqueous environments. These techniques can provide essential information such as chemical adsorption, structure, and reactivity at interfaces. In this perspective, these techniques are presented with obvious advantages for studying the chemical properties of pollutants adsorbed to environmental and biological interfaces.
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Affiliation(s)
- Andrew P Carpenter
- School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon 97331
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7
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Pullanchery S, Zhang L, Kulik S, Roke S. Interfacial Inversion, Interference, and IR Absorption in Vibrational Sum Frequency Scattering Experiments. J Phys Chem B 2023; 127:6795-6803. [PMID: 37470215 PMCID: PMC10405221 DOI: 10.1021/acs.jpcb.3c02727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/26/2023] [Indexed: 07/21/2023]
Abstract
Molecular interfacial structure greatly determines the properties of nano- and microscale systems. Vibrational sum frequency scattering (SFS) spectroscopy is a unique interface-selective tool to measure the interfacial vibrational spectrum of sub-micron to micron-scale objects dispersed in liquid and solid media. The interfacial structure is extracted from the interfacial susceptibility, a physical property derived from the intensity. Here, we describe the effect of infrared absorption that occurs in a bulk medium that is spectroscopically complex and use the results to investigate the effects of interfacial inversion, interfacial interference, and interfacial interference combined with absorption. We use the same three chemicals to do so, hexadecane oil, water, and a neutral Span80 surfactant. For all cases, the effective surface susceptibility can be retrieved from the intensity. We further find that inverting the phases results in different interfacial structures, even though they are composed of the same three chemicals, and explain this in terms of the different interactions that are necessary to stabilize the drops: steric stabilization for water drops in oil vs. charge stabilization for oil drops in water. Interfacial interference can be used to estimate the surface density of different compounds.
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Affiliation(s)
- S. Pullanchery
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering (IBI), School
of Engineering (STI), École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - L. Zhang
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering (IBI), School
of Engineering (STI), École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - S. Kulik
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering (IBI), School
of Engineering (STI), École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - S. Roke
- Laboratory
for Fundamental BioPhotonics, Institute of Bioengineering (IBI), School
of Engineering (STI), École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute
of Materials Science and Engineering (IMX), School of Engineering
(STI), École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Lausanne
Centre for Ultrafast Science, École
Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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8
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Kurapati R, Natarajan U. Tacticity and Ionization Effects on Adsorption Behavior of Poly(acrylic acid) and Poly(methacrylic acid) at the CCl 4–H 2O Interface Revealed by MD Simulations. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c02416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Raviteja Kurapati
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai600036, India
| | - Upendra Natarajan
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai600036, India
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9
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Xie K, Gorin B, Cerbus RT, Alvarez L, Rampnoux JM, Kellay H. Activity Induced Rigidity of Liquid Droplets. PHYSICAL REVIEW LETTERS 2022; 129:138001. [PMID: 36206417 DOI: 10.1103/physrevlett.129.138001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/18/2022] [Accepted: 08/25/2022] [Indexed: 06/16/2023]
Abstract
Here we show that encapsulating active Janus particles within a drop renders it more resistant to deformation. This drop is deformed under the action of an extensional flow. Such deformation is primarily resisted by the drop interfacial tension. When the particles are active under the action of laser illumination, the deformation decreases signaling an increase in effective tension or Laplace pressure. This increase is attributed to the activity of the particles. Our results using numerous drop sizes, particle number densities, and active velocities show that the obtained increase agrees surprisingly well, over an extended range, with a standard expression for the pressure engendered by an ensemble of active particles, proposed years ago but not tested yet in three dimensions.
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Affiliation(s)
- Kaili Xie
- Université de Bordeaux, CNRS, LOMA, UMR 5798, F-33405 Talence, France
| | - Benjamin Gorin
- Université de Bordeaux, CNRS, LOMA, UMR 5798, F-33405 Talence, France
| | - Rory T Cerbus
- Université de Bordeaux, CNRS, LOMA, UMR 5798, F-33405 Talence, France
| | - Laura Alvarez
- Université de Bordeaux, CNRS, CRPP, UMR 5031, 33600 Pessac, France
| | | | - Hamid Kellay
- Université de Bordeaux, CNRS, LOMA, UMR 5798, F-33405 Talence, France
- Institut Universitaire de France, 75005 Paris, France
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10
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Using Aerosol OT in Hexane Solution to Synthesize Calcium Nitrate Self-Healing Refined Microcapsules for Construction Applications. BUILDINGS 2022. [DOI: 10.3390/buildings12060751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The micro-encapsulation procedure of calcium nitrate in urea-formaldehyde shell is well known. The most recent developed method for the synthesis of the calcium nitrate self-healing micro-capsules was based on the in-situ polymerization using water-in-oil emulsion. Although the microcapsules’ yield was significantly improved using this approach, incorporating the micro-capsules into concrete mixes has been found to reduce strength. One potential strength reduction cause might be the presence of sulfonic acid as a component in the continuous (oil) phase. As the anionic surfactant, Aerosol OT (AOT) has been widely used to prepare water-in-oil emulsions and to form aggregates in non-polar solvents; submicron calcium nitrate refined microcapsules were synthesized using AOT in hexane solution. While the aqueous phase in the original encapsulation procedure has not been altered, the continuous organic phase was prepared by dissolving AOT in hexane. The prepared microcapsules were characterized using Scanning Electron Microscopy (SEM). The preliminary assessment of the effect of incorporating of the refined microcapsules into cementitious materials has been carried out by preparing mortar mixes using 75% capsules’ concentration (by weight of cement). The reported yield values, average shell thickness, and average diameter of the prepared microcapsules were found satisfactory. Moreover, the mortar samples containing calcium nitrate refined microcapsules that were prepared using the proposed method did not experience significant reduction in their mechanical properties. Hence, such encapsulation procedure may be adopted for further investigation of the self-healing efficiency in cementitious materials of the microcapsules prepared using the proposed procedure. Future work shall be directed towards this end.
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11
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Vratsanos MA, Gianneschi NC. Direct Observation of Emulsion Morphology, Dynamics, and Demulsification. ACS NANO 2022; 16:7783-7793. [PMID: 35302741 PMCID: PMC9836053 DOI: 10.1021/acsnano.2c00199] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Herein, we present the direct observation and quantification of a water-in-oil (w/o) emulsion, its destabilization, and the effect of additives on such processes at the nanoscale. This is achieved via liquid phase transmission electron microscopy (LPTEM), wherein a small volume of emulsion is encapsulated against vacuum in its liquid state to allow observation of its initial morphology and its evolution over time at excellent spatial and temporal resolution. Emulsions of this class are useful for delivering payloads of materials insoluble in their delivery medium and are currently widely used across food science, pharmaceuticals, and environmental applications. However, their utility is inherently limited by their thermodynamic tendency to demulsify, eventually leading to bulk phase separation. This occurs via several degradation mechanisms, operating at times collectively, and which are difficult to differentiate via traditional ensemble methods (e.g., light scattering), obscuring mechanistic nuances. LPTEM as a characterization technique has the potential to augment our understanding of emulsion behavior and improve performance and formulations. In this work, we also emphasize the importance of the included videographic Supporting Information data in demonstrating the behavior of the studied materials.
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Affiliation(s)
- Maria A Vratsanos
- Department of Materials Science & Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Nathan C Gianneschi
- Department of Materials Science & Engineering, Northwestern University, Evanston, Illinois 60208, United States
- International Institute for Nanotechnology, Simpson Querrey Institute, Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Department of Chemistry, Department of Biomedical Engineering, Department of Pharmacology, Northwestern University, Evanston, Illinois 60208, United States
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12
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Choose your own adventure: Picosecond or broadband vibrational sum-frequency generation spectroscopy. Biointerphases 2022; 17:031201. [PMID: 35513338 DOI: 10.1116/6.0001844] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Vibrational sum-frequency generation (VSFG) spectroscopy is a method capable of measuring chemical structure and dynamics within the interfacial region between two bulk phases. At the core of every experimental system is a laser source that influences the experimental capabilities of the VSFG spectrometer. In this article, we discuss the differences between VSFG spectrometers built with picosecond and broadband laser sources as it will impact everything from material costs, experimental build time, experimental capabilities, and more. A focus is placed on the accessibility of the two different SFG systems to newcomers in the SFG field and provides a resource for laboratories considering incorporating VSFG spectroscopy into their research programs. This Tutorial provides a model decision tree to aid newcomers when determining whether the picosecond or femtosecond laser system is sufficient for their research program and navigates through it for a few specific scenarios.
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13
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Pier Villegas G, Alvarado Mendoza AG, Guerrero Ram U EDrez LG, Rosales-Rivera LC, Aguilar J, Moscoso S U E Nchez FJ. Polymerization of aniline hydrochloride in reverse of microemulsion by batch and semicontinuous process using ionic and nonionic surfactants. Des Monomers Polym 2022; 25:89-97. [PMID: 35431615 PMCID: PMC9009907 DOI: 10.1080/15685551.2022.2063011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The polymerization of aniline hydrochloride by inverse microemulsion in a batch process and the semicontinuous process was studied as a function of the surfactant ionic and nonionic. Polymerizations were carried out at 60°C for 4 h with a yield polymer of circa 67 and 27% wt. for ionic and nonionic surfactants. The conductivity of synthesized polyaniline by the semicontinuous process is higher up to three orders of magnitude than that of the batch process for both surfactants. The calculating degree of oxidation by UV-Vis showed the relative intensities of the quinoid to benzenoid unit around one. The morphology was determined by Scanning Electron Microscopy (SEM) and observed that the formation of the different morphologies is due to the self-assembly behavior of surfactant. The diameter z-average particle size (Dz) was studied by Transmission Electron Microscopy (TEM), which determined that the diameter particle in a semicontinuous state is larger than the one produced in a batch; this is due to the control of monomer addition in the system. These findings suggest that the polymerization process and the type of surfactant influence the properties of polyaniline.
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Affiliation(s)
- G Pier Villegas
- Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - A G Alvarado Mendoza
- Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - L G Guerrero Ram U EDrez
- Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - L C Rosales-Rivera
- Departamento de Ingeniería Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - J Aguilar
- Departamento de Ciencias Tecnológicas, Centro Universitario de la Ciénega, Ocotlán, Jalisco, México
| | - F J Moscoso S U E Nchez
- Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara, Jalisco, México
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14
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Molecular Dynamics Simulation and Cryo-Electron Microscopy Investigation of AOT Surfactant Structure at the Hydrated Mica Surface. MINERALS 2022. [DOI: 10.3390/min12040479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Structural properties of the anionic surfactant dioctyl sodium sulfosuccinate (AOT or Aerosol-OT) adsorbed on the mica surface were investigated by molecular dynamics simulation, including the effect of surface loading in the presence of monovalent and divalent cations. The simulations confirmed recent neutron reflectivity experiments that revealed the binding of anionic surfactant to the negatively charged surface via adsorbed cations. At low loading, cylindrical micelles formed on the surface, with sulfate head groups bound to the surface by water molecules or adsorbed cations. Cation bridging was observed in the presence of weakly hydrating monovalent cations, while sulfate groups interacted with strongly hydrating divalent cations through water bridges. The adsorbed micelle structure was confirmed experimentally with cryogenic electronic microscopy, which revealed micelles approximately 2 nm in diameter at the basal surface. At higher AOT loading, the simulations reveal adsorbed bilayers with similar surface binding mechanisms. Adsorbed micelles were slightly thicker (2.2–3.0 nm) than the corresponding bilayers (2.0–2.4 nm). Upon heating the low loading systems from 300 K to 350 K, the adsorbed micelles transformed to a more planar configuration resembling bilayers. The driving force for this transition is an increase in the number of sulfate head groups interacting directly with adsorbed cations.
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15
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Kataoka-Hamai C, Kawakami K. Hydrocarbon Penetration into Phospholipid Monolayers Formed at Hydrocarbon-Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:3720-3728. [PMID: 35289166 DOI: 10.1021/acs.langmuir.1c03269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Phospholipid monolayers formed at oil-water interfaces are used for various biological applications. However, monolayer structures are not well understood. Herein, we investigated hydrocarbon partitioning in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine monolayers formed at hydrocarbon-water interfaces using fluorescence microscopy and pendant drop tensiometry. The monolayers strongly interacted with squalene, n-hexadecane, n-tetradecane, n-dodecane, n-decane, and n-butylcyclohexane. These alkane and alkylcyclohexane molecules remained within the monolayers during area compression. In contrast, the monolayers interacted weakly with n-pentylbenzene and n-butylbenzene. These alkylbenzenes were gradually removed from the monolayers upon area compression and were completely expelled at an area per lipid of ∼70 Å2. Surface pressure analysis indicated that the ability of hydrocarbons to penetrate the monolayers was enhanced in the order of n-butylbenzene < n-pentylbenzene < n-butylcyclohexane < n-hexadecane.
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Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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16
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Machado N, Bruininks BMH, Singh P, Dos Santos L, Dal Pizzol C, Dieamant GDC, Kruger O, Martin AA, Marrink SJ, Souza PCT, Favero PP. Complex nanoemulsion for vitamin delivery: droplet organization and interaction with skin membranes. NANOSCALE 2022; 14:506-514. [PMID: 34913938 DOI: 10.1039/d1nr04610a] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Lipid nanoemulsions are promising nanomaterials for drug delivery applications in food, pharmaceutical and cosmetic industries. Despite the noteworthy commercial interest, little is known about their supramolecular organization, especially about how such multicomponent formulations interact with cell membranes. In the present work, coarse-grained molecular dynamics simulations have been employed to study the self-assembly of a 15-component lipid nanoemulsion droplet containing vitamins A and E for skin delivery. Our results display aspects of the unique "onion-like" agglomeration between the chemical constituents in the different layers of the lipid nanodroplet. Vitamin E molecules are more concentrated in the center of the droplet together with other hydrophobic constituents such as the triglycerides with long tails. On the other hand, vitamin A occupies an intermediate layer between the core and the co-emulsifier surface of the nanodroplet, together with lecithin phospholipids. Coarse-grained molecular dynamics simulations were also performed to provide insight into the first steps involved in absorption and penetration of the nanodroplet through skin membrane models, representing an intracellular (hair follicle infundibulum) and intercellular pathway (stratum corneum) through the skin. Our data provide a first view on the complex organization of commercial nanoemulsion and its interaction with skin membranes. We expect our results to open the way towards the rational design of such nanomaterials.
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Affiliation(s)
- Neila Machado
- Institute of Research and Development, Universidade do Vale do Paraíba, Av. Shishima Hifumi 2911, 12244-000, São José dos Campos, São Paulo, Brazil
- UFABC Universidade Federal do ABC, Avenida dos Estados, 5001, 09210-580, Santo André, São Paulo, Brazil.
| | - Bart M H Bruininks
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Priyanka Singh
- Institute of Research and Development, Universidade do Vale do Paraíba, Av. Shishima Hifumi 2911, 12244-000, São José dos Campos, São Paulo, Brazil
| | - Laurita Dos Santos
- Institute of Research and Development, Universidade do Vale do Paraíba, Av. Shishima Hifumi 2911, 12244-000, São José dos Campos, São Paulo, Brazil
- Biomedical Engineering Innovation Center, Biomedical Vibrational Spectroscopy Group. Universidade Brasil UnBr, Rua Carolina Fonseca 235, 08230-030, Itaquera, São Paulo, Brazil.
| | - Carine Dal Pizzol
- Grupo Boticário, Av. Rui Barbosa, 4110, 83055-010, Parque da Fonte, São José dos Pinhais, Paraná, Brazil
| | - Gustavo de C Dieamant
- Grupo Boticário, Av. Rui Barbosa, 4110, 83055-010, Parque da Fonte, São José dos Pinhais, Paraná, Brazil
| | - Odivania Kruger
- Grupo Boticário, Av. Rui Barbosa, 4110, 83055-010, Parque da Fonte, São José dos Pinhais, Paraná, Brazil
| | - Airton A Martin
- Biomedical Engineering Innovation Center, Biomedical Vibrational Spectroscopy Group. Universidade Brasil UnBr, Rua Carolina Fonseca 235, 08230-030, Itaquera, São Paulo, Brazil.
- DermoProbes - Research, Innovation and Technological Development, Av. Cassiano Ricardo, 601, Sala 73-74, 12246-870, São José dos Campos, SP, Brazil
| | - Siewert J Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Paulo C T Souza
- Groningen Biomolecular Sciences and Biotechnology Institute and Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
- Molecular Microbiology and Structural Biochemistry (MMSB, UMR 5086), CNRS, University of Lyon, Lyon, France.
| | - Priscila P Favero
- Biomedical Engineering Innovation Center, Biomedical Vibrational Spectroscopy Group. Universidade Brasil UnBr, Rua Carolina Fonseca 235, 08230-030, Itaquera, São Paulo, Brazil.
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17
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van Dam EP, Gouzy R, Pelan E, Velikov KP, Bakker HJ. Water reorientation dynamics in colloidal water-oil emulsions. Phys Chem Chem Phys 2021; 23:27024-27030. [PMID: 34846395 DOI: 10.1039/d1cp03182a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study the molecular-scale properties of colloidal water-oil emulsions consisting of 120-290 nm oil droplets embedded in water. This type of emulsion can be prepared with low concentrations of surfactants and is usually kinetically stable. Even though colloidal water-oil emulsions are used ubiquitously, their molecular properties are still poorly understood. Here we study the orientational dynamics of water molecules in these emulsions using polarization resolved pump-probe infrared spectroscopy, for varying surfactant concentrations, droplet sizes, and temperatures. We find that the majority of the water molecules reorients with the same time constant as in bulk water, while a small fraction of the water molecules reorients on a much longer time scale. These slowly reorienting water molecules are interacting with the surface of the oil droplets. The fraction of slowly orienting water molecules is proportional to the oil volume fraction, and shows a negligible dependence on the average droplet size. This finding indicates that the total surface area of the oil droplets is quite independent of the average droplet size, which indicates that the larger oil droplets are quite corrugated, showing large protrusions into the water phase.
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Affiliation(s)
| | - Roland Gouzy
- Unilever Innovation Centre Wageningen, Bronland 14, 6708 WH Wageningen, The Netherlands
| | - Eddie Pelan
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Krassimir P Velikov
- Unilever Innovation Centre Wageningen, Bronland 14, 6708 WH Wageningen, The Netherlands.,Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.,Soft Condensed Matter, Debye Institute for NanoMaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Huib J Bakker
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
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18
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Sun T, Wyslouzil BE. Freezing of Dilute Aqueous-Alcohol Nanodroplets: The Effect of Molecular Structure. J Phys Chem B 2021; 125:12329-12343. [PMID: 34709826 DOI: 10.1021/acs.jpcb.1c06188] [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
We investigate vapor-liquid nucleation and subsequent freezing of aqueous-alcohol nanodroplets containing 1-pentanol, 1-hexanol, and their 3-isomers. The aerosols are produced in a supersonic nozzle, where condensation and freezing are characterized by static pressure and Fourier transform Infrared (FTIR) spectroscopy measurements. At fixed water concentrations, the presence of alcohol enables particle formation at higher temperatures since both the equilibrium vapor pressure above the critical clusters and the cluster interfacial free energy are decreased relative to the pure water case. The disappearance of a small free OH peak, observed for pure water droplets, when alcohols are added and shifts in the CH peaks as a function of alcohol chain length reveal varying surface partitioning preferences of the alcohols. Changes in the FTIR spectra during freezing, as well as changes in the ice component derived from self-modeling curve resolution analysis, show that 1-hexanol and 1-pentanol perturb freezing less than their branched isomers do. This behavior may reflect the molecular footprints of the alcohols, the available surface area of the droplets, and not only alcohol solubility. The presence of alcohols also lowers the freezing temperature relative to that of pure water, but when there is clear evidence for the formation of ice, the ice nucleation rates change by less than a factor of ∼2-3 for all cases studied.
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Affiliation(s)
- Tong Sun
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States
| | - Barbara E Wyslouzil
- William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210, United States.,Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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19
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Tran E, Richmond GL. Interfacial Steric and Molecular Bonding Effects Contributing to the Stability of Neutrally Charged Nanoemulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:12643-12653. [PMID: 34662126 DOI: 10.1021/acs.langmuir.1c02020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In cosmetic, pharmaceutical, and food applications, many active ingredients have limited bioavailability in an aqueous environment, and in that context, nanoemulsions provide a mechanism for encapsulation, protection, and transport. These dispersed oil droplets are on the order of 100s of nanometers in diameter and owe their long-term stability to emulsifiers that are commonly charged. More recently, applications have been utilizing nonionic species as stabilizing agents due to their enhanced biosafety. DLVO (named after Derjaguin, Landau, Verwey, and Overbeek) theory has been central in the description of colloid stability, which emphasizes repulsive electrostatic forces, while extended DLVO theory also accounts for steric effects. Past studies of nanoemulsions have largely employed charged surfactants and polyelectrolytes, making it difficult to decouple electrostatic and steric effects as they relate to droplet stability. To better understand steric and molecular factors contributing to the stability of "uncharged" droplets, we have created nanoemulsions with sodium dodecyl sulfate (SDS) and poly(N-vinylacetamide) (PNVA). Though SDS is anionic, with PNVA coating the droplet surfaces, the ζ-potentials of these nanoemulsions are ∼0 mV. Despite minimizing electrostatic contributions, these nanoemulsions are stable for upward of a month with interesting dynamics. By employing dynamic light scattering, vibrational sum frequency scattering spectroscopy, and calculating interaction pair potentials using extended DLVO theory, we learn that the thickness of the PNVA layer plays a critical role in stabilizing these "uncharged" nanoemulsions. Beyond the sterics, the molecular conformation of the PNVA strands also contributes to the droplet stability. The adsorbed PNVA strands are shown to form stratified, rigid polymer networks that prevent the nanoemulsions from rapid destabilization.
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Affiliation(s)
- Emma Tran
- University of Oregon, Eugene, Oregon 97403, United States
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20
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Foster MJ, Carpenter AP, Richmond GL. Dynamic Duo: Vibrational Sum Frequency Scattering Investigation of pH-Switchable Carboxylic Acid/Carboxylate Surfactants on Nanodroplet Surfaces. J Phys Chem B 2021; 125:9629-9640. [PMID: 34402616 DOI: 10.1021/acs.jpcb.1c05508] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Surfactants containing pH-switchable, carboxylic acid moieties are utilized in a variety of environmental, industrial, and biological applications that require controlled stability of hydrophobic droplets in water. For nanoemulsions, kinetically stable oil droplets in water, surface adsorption of the anionic form of the carboxylic acid surfactant stabilizes the droplet, whereas a dominant surface presence of the neutral form leads to destabilization. Through the use of dynamic light scattering, ζ-potential, and vibrational sum frequency scattering spectroscopy (VSFSS), we investigate this mechanism and the relative surface population of the neutral and charged species as pH is adjusted. We find that the relative population of the two surfactant species at the droplet surface is distinctly different than their bulk equilibrium concentrations. The ζ-potential measurements show that the surface concentration of the charged surfactant stays nearly constant throughout the stabilizing pH range. In contrast, VSFSS shows that the neutral carboxylic acid form increasingly adsorbs to the surface with increased acidity. The spectral features of the headgroup vibrational modes confirm this behavior and go further to reveal additional molecular details of their adsorption. A significant hydrogen-bonding interaction occurs between the headgroups that, along with hydrophobic chain-chain interactions, assists in drawing more carboxylic acid surfactant to the interface. The charged surfactant provides the stabilizing force for these droplets, while the neutral surfactant introduces complexity to the interfacial structure as the pH is lowered. The results are significantly different than what has been found for the planar oil/water studies where stabilization of the interface is not a factor.
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Affiliation(s)
- Marc J Foster
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Andrew P Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
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21
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Carpenter AP, Foster MJ, Jones KK, Richmond GL. Effects of Salt-Induced Charge Screening on AOT Adsorption to the Planar and Nanoemulsion Oil-Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:8658-8666. [PMID: 34260854 DOI: 10.1021/acs.langmuir.0c03606] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nanoemulsions, nanosized droplets of oil, are easily stabilized by interfacial electric fields from the adsorption of ionic surfactants. While mean-field theories can be used to describe the impact of these interfacial fields on droplet stability, the influence of these fields on the adsorption properties of ionic surfactants is not well-understood. In this work, we study the adsorption of the surfactant sodium dioctyl sulfosuccinate (AOT) at the nanoemulsion and planar oil-water interfaces and investigate how salt-induced charge-screening affects AOT adsorption. In the absence of salt, vibrational sum-frequency scattering spectroscopy measurements reveal the ΔGads and the maximum surface density is the same for AOT at the hexadecane nanoemulsion surface as at the planar hexadecane-H2O interface. Upon the addition of NaCl, an increase in AOT surface density is detected at both interfaces, indicating that repulsive electrostatic interactions between AOT monomers are the dominant force limiting surfactant adsorption at both interfaces. The bulky alkyl chains of AOT molecules cause our observations in this study to differ from those found in previous studies investigating the adsorption of linear-chain ionic surfactants to the nanoemulsion surface. These results provide necessary information for understanding factors limiting the adsorption of ionic surfactants to nanodroplet surfaces and highlight the need for further studies into the adsorption properties of more complex macromolecules at nanoemulsion surfaces.
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Affiliation(s)
- Andrew P Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Marc J Foster
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Konnor K Jones
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
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22
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Kataoka-Hamai C, Kawakami K. Determining the Dependence of Interfacial Tension on Molecular Area for Phospholipid Monolayers Formed at Silicone Oil-Water and Tricaprylin-Water Interfaces by Vesicle Fusion. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:7527-7535. [PMID: 34115510 DOI: 10.1021/acs.langmuir.1c01021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phospholipid monolayers formed at oil-water interfaces have been used to explore biological interface properties. Thus, monolayer systems need to be quantitatively understood. Previously, we investigated the formation of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) monolayers at silicone oil-water interfaces to determine the dependence of interfacial tension, γ, on the area per lipid, a, compared to that of the closely packed monolayers, acp. This study aims to develop a method to obtain the γ-a relationship from the γ-a/acp data by investigating POPC monolayers at the silicone oil-water and tricaprylin-water interfaces. Pendant drop tensiometry was used to obtain the dependence of γ on a/acp. Furthermore, by calculating the surface pressure, Π, from γ and multiplying a/acp with an estimated acp value, the dependence of Π on a was obtained. When a value approximately equal to the a of POPC bilayers was assigned to acp, the resultant Π-a profile partially or approximately completely overlapped with the Π-a isotherms obtained for the monolayers at the air-water interface using a Langmuir trough. The overlap for the silicone oil-water interface occurred at a ≤ 77 Å2, while that for the tricaprylin-water interface occurred in approximately the entire a region. The results indicate that the Π of the condensed monolayers is little affected by bulk oil. Thus, the γ-a relationship for the oil-water interface can be determined by comparing the compression isotherm with the one obtained for the air-water interface.
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Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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23
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Tran E, Mapile AN, Richmond GL. Peeling back the layers: Investigating the effects of polyelectrolyte layering on surface structure and stability of oil-in-water nanoemulsions. J Colloid Interface Sci 2021; 599:706-716. [PMID: 33984763 DOI: 10.1016/j.jcis.2021.04.115] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/14/2021] [Accepted: 04/21/2021] [Indexed: 12/21/2022]
Abstract
HYPOTHESIS Layer-by-layer deposition of polyelectrolytes is a useful technique for modifying surface functionalities. For drug delivery systems, alternating layers of biopolymers coat nanoemulsions, which house and protect the cargo until the time and destination of delivery. Here, we investigate molecular factors contributing to the stability and interfacial properties of nanoemulsions prepared by a co-adsorption of polymers poly(styrene sulfonate) and polyethylenimine (PEI), and surfactant dodecyltrimethylammonium bromide. We hypothesize the interplay between electrosteric and hydrophobic effects upon multi-polymer co-adsorption contributes to both macroscopic and molecular-level interfacial properties of nanoemulsions. EXPERIMENTS To probe interfacial layering properties, we use vibrational sum frequency scattering spectroscopy with ζ-potential measurements to determine the adsorptive behavior and molecular conformational arrangement of the polymer layers. Complementing these interfacial studies are dynamic light scattering experiments measuring the nanoemulsion size distribution and polydispersity index over a 30-day period. FINDINGS Our light scattering, ζ-potential, and spectroscopic results of the nanoemulsion surface show that the duration of droplet stability and the degree of molecular orientation of adsorbed polymers can be tuned by surfactant concentration, PEI concentration, and pH. These results illustrate how molecular surface properties of multi-polymer coated nanoemulsions contribute to synergistic effects and droplet stability, enabling advancements in applications surrounding biopharmaceuticals, cosmetics, and food sciences.
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Affiliation(s)
- Emma Tran
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, United States.
| | - Ashley N Mapile
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, United States.
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403, United States.
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24
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Baryiames CP, Garrett P, Baiz CR. Bursting the bubble: A molecular understanding of surfactant-water interfaces. J Chem Phys 2021; 154:170901. [PMID: 34241044 DOI: 10.1063/5.0047377] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Surfactant science has historically emphasized bulk, thermodynamic measurements to understand the microemulsion properties of greatest industrial significance, such as interfacial tensions, phase behavior, and thermal stability. Recently, interest in the molecular properties of surfactants has grown among the physical chemistry community. This has led to the application of cutting-edge spectroscopic methods and advanced simulations to understand the specific interactions that give rise to the previously studied bulk characteristics. In this Perspective, we catalog key findings that describe the surfactant-oil and surfactant-water interfaces in molecular detail. We emphasize the role of ultrafast spectroscopic methods, including two-dimensional infrared spectroscopy and sum-frequency-generation spectroscopy, in conjunction with molecular dynamics simulations, and the role these techniques have played in advancing our understanding of interfacial properties in surfactant microemulsions.
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Affiliation(s)
- Christopher P Baryiames
- Department of Chemistry, University of Texas at Austin, 105 E 24th St. Stop A5300, Austin, Texas 78712-1224, USA
| | - Paul Garrett
- Department of Chemistry, University of Texas at Austin, 105 E 24th St. Stop A5300, Austin, Texas 78712-1224, USA
| | - Carlos R Baiz
- Department of Chemistry, University of Texas at Austin, 105 E 24th St. Stop A5300, Austin, Texas 78712-1224, USA
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25
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Heo E, Noh S, Lee U, Le TH, Lee H, Jo H, Lee S, Yoon H. Surfactant-in-Polymer Templating for Fabrication of Carbon Nanofibers with Controlled Interior Substructures: Designing Versatile Materials for Energy Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2007775. [PMID: 33739582 DOI: 10.1002/smll.202007775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/17/2021] [Indexed: 06/12/2023]
Abstract
A simple, scalable, surfactant-in-polymer templating approach is demonstrated to create controlled long-range secondary substructures in a primary structure. A metal bis(2-ethylhexyl) sulfosuccinate (MAOT) as the surfactant is shown to be capable of serving as a sacrificial template and metal precursor in carbon nanofibers. The low interfacial tension and controllable dimensions of the MAOT are maintained in the solid-phase polymer, even during electrospinning and heat-treatment processes, allowing for the long-range uniform formation of substructures in the nanofibers. The MAOT content is found to be a critical parameter for tailoring the diameter of the nanofibers and their textural properties, such as size and volume of interior pores. The metal counterion species in the MAOT determine the introduction of metallic phases in the nanofiber interior. The incorporation of MAOT with Na as the counterion into the polymer phase leads to the formation of a built-in pore structure in the nanofibers. In contrast, MAOT with Fe as a counterion generates unique iron-in-pore substructures in the nanofibers (FeCNFs). The FeCNFs exhibit outstanding charge storage and water splitting performances. As a result, the MAOT-in-polymer templating approach can be extended to combinations of various metal precursors and thus create desirable functionalities for different target applications.
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Affiliation(s)
- Eunseo Heo
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Seonmyeong Noh
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Unhan Lee
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Thanh-Hai Le
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Haney Lee
- Alan G. MacDiarmid Energy Research Institute, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Hyemi Jo
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Sanghyuck Lee
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
| | - Hyeonseok Yoon
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
- Alan G. MacDiarmid Energy Research Institute, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 61186, South Korea
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26
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Wang Z, Li P, Ma K, Chen Y, Webster JRP, Campana M, Yan Z, Penfold J, Thomas RK. Multivalent counterion induced multilayer adsorption at the air-water interface in dilute Aerosol-OT solutions. J Colloid Interface Sci 2021; 597:223-232. [PMID: 33872879 DOI: 10.1016/j.jcis.2021.03.183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/29/2021] [Accepted: 03/30/2021] [Indexed: 11/28/2022]
Abstract
The formation of surface multilayer structures, induced by the addition of multivalent counterions in dilute surfactant solutions, has been widely observed in a range of anionic surfactants. The phenomenon is associated with the ability to manipulate surface properties, especially in the promotion of enhanced surface wetting, and in the presence of an extensive near surface reservoir for rapid surface delivery of surfactant and other active components. HYPOTHESIS In the single alkyl chain anionic surfactants, such as sodium dodecysulfate, SDS, sodium alkylethoxylsulfate, SAES, and alkylestersulfonate, AES, surface multilayer formation is promoted by trivalent counterions such as Al3+, and is generally not observed with divalent counterions, such as Ca2+ or with monovalent counterions. In the di-alkyl chain anionic surfactant, dodecylbenzenesulfonate, LAS, surface multilayer formation now occurs in the presence of divalent counterions. It is attributed to the closer proximity of a bulk lamellar phase, resulting in a greater tendency for surface multilayer formation, and hence should occur in other di-alkyl chain anionic surfactants. EXPERIMENTS Aerosol-OT, AOT, is one of the most commonly used di-alkyl chain anionic surfactants, and is extensively used as an emulsifying, wetting and dispersing agent. This paper reports on predominantly neutron reflectivity, NR, measurements which explore the nature of surface multilayer formation of the sodium salt of AOT at the air-solution interface with the separate addition of Ca2+ and Al3+ counterions. FINDINGS In the AOT concentration range 0.5 to 2.0 mM surface multilayer formation occurs at the air-solution interface with the addition of Ca2+ or Al3+ counterions. Although the evolution in the surface structure with surfactant and counterion concentration is broadly similar to those reported for SDS, SAES and AES, some notable differences occur. In particular the surfactant and counterion concentration thresholds for surface multilayer formation are higher for Ca2+ than for Al3+. The differences encountered reflect the greater affinity of the di-alkyl chain structure for lamellar formation, and how the surface packing is controlled in part by the headgroup structure and the associated counterion binding affinity.
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Affiliation(s)
- Zi Wang
- School of Science, State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, China; ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Peixun Li
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Kun Ma
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Yao Chen
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - John R P Webster
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Mario Campana
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Zifeng Yan
- School of Science, State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Qingdao 266580, China.
| | - Jeff Penfold
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK; Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK.
| | - Robert K Thomas
- Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ, UK
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Carpenter AP, Christoffersen EL, Mapile AN, Richmond GL. Assessing the Impact of Solvent Selection on Vibrational Sum-Frequency Scattering Spectroscopy Experiments. J Phys Chem B 2021; 125:3216-3229. [PMID: 33739105 DOI: 10.1021/acs.jpcb.1c00188] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The development of vibrational sum-frequency scattering (S-VSF) spectroscopy has opened the door to directly probing nanoparticle surfaces with an interfacial and chemical specificity that was previously reserved for planar interfacial systems. Despite its potential, challenges remain in the application of S-VSF spectroscopy beyond simplified chemical systems. One such challenge includes infrared absorption by an absorptive continuous phase, which will alter the spectral lineshapes within S-VSF spectra. In this study, we investigate how solvent vibrational modes manifest in S-VSF spectra of surfactant stabilized nanoemulsions and demonstrate how corrections for infrared absorption can recover the spectral features of interfacial solvent molecules. We also investigate infrared absorption for systems with the absorptive phase dispersed in a nonabsorptive continuous phase to show that infrared absorption, while reduced, will still impact the S-VSF spectra. These studies are then used to provide practical recommendations for anyone wishing to use S-VSF to study nanoparticle surfaces where absorptive solvents are present.
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Affiliation(s)
- Andrew P Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Evan L Christoffersen
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Ashley N Mapile
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
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Arif Kamal M, Pal A. Topological changes accompanying the phase transitions in AOT-water binary system in the presence of a strongly binding counter-ion. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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29
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Behera US, Sangwai JS. Nanofluids of Kaolinite and Silica in Low Saline Seawater (LowSal) with and without Surfactant: Interfacial Tension and Wettability Alteration of Oil–Water–Rock System for Low Salinity-Enhanced Oil Recovery. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c04853] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Uma Sankar Behera
- Enhanced Oil Recovery Laboratory, Petroleum Engineering Programme, Department of Ocean Engineering, Indian Institute of Technology Madras, Chennai 600 036, India
| | - Jitendra S. Sangwai
- Enhanced Oil Recovery Laboratory, Petroleum Engineering Programme, Department of Ocean Engineering, Indian Institute of Technology Madras, Chennai 600 036, India
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Baryiames CP, Ma E, Baiz CR. Ions Slow Water Dynamics at Nonionic Surfactant Interfaces. J Phys Chem B 2020; 124:11895-11900. [DOI: 10.1021/acs.jpcb.0c09086] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher P. Baryiames
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
| | - Emily Ma
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Carlos R. Baiz
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States
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31
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Kataoka-Hamai C, Kawakami K. Determination of the Coverage of Phosphatidylcholine Monolayers Formed at Silicone Oil–Water Interfaces by Vesicle Fusion. J Phys Chem B 2020; 124:8719-8727. [DOI: 10.1021/acs.jpcb.0c06310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chiho Kataoka-Hamai
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kohsaku Kawakami
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
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32
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Smolentsev N, Roke S. Self-Assembly at Water Nanodroplet Interfaces Quantified with Nonlinear Light Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9317-9322. [PMID: 32654491 DOI: 10.1021/acs.langmuir.0c01887] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The interfaces of water micro- and nanodroplets drive environmental, medical, catalytic, biological, and chemical biphasic processes. The interfacial droplet structure and electrostatics greatly determine the reactivity and efficiency of these processes. Droplet interfacial properties are elusive and generally inferred from bulk measurements and are therefore anything but exact. Here, we quantify the interfacial ordering of water and the electrostatic surface potential of nanoscale water droplets in an apolar liquid using angle-resolved polarimetric second-harmonic scattering. We also present a method to determine the amount of free charges in the hydrophobic phase, reaching a sensitivity that is 3 orders of magnitude better than conductivity measurements. Investigating the structural and surface electrostatic changes induced by AOT surfactant adsorption, we find that both the hydrogen bonding as well as the electrostatics strongly depend on the surfactant concentration. Above the critical micelle concentration, the interface mediates micelle self-assembly.
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Affiliation(s)
- N 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
| | - S 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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33
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Tran E, Carpenter AP, Richmond GL. Probing the Molecular Structure of Coadsorbed Polyethylenimine and Charged Surfactants at the Nanoemulsion Droplet Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9081-9089. [PMID: 32668900 DOI: 10.1021/acs.langmuir.0c01095] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nanoemulsions, nanoscale oil droplets dispersed in an aqueous medium, can be stabilized by polymer-surfactant (PS) mixtures, making them ubiquitous in commercial, industrial, and pharmaceutical applications. It is well-known that the presence of PS layers coadsorbed at the droplet surface plays a significant role in droplet stability and functionality; however, little is understood about the molecular nature of this coadsorption. Such insights are especially important for application in drug delivery where physiological conditions can vary the environmental pH and significantly impact stabilization. Hence, the focus of this study examines the surface properties of ∼300 nm nanoemulsions stabilized by the coadsorption of polyethylenimine (PEI) and charged alkyl surfactants sodium dodecyl sulfate (SDS) and dodecyltrimethylammonium bromide (DTAB). PEI is a common charge-tunable polymer used in nanocarrier templates. This study employs vibrational sum frequency scattering spectroscopy, coupled with ζ-potential and surface pressure measurements performed as a function of varying concentrations and pH. The surface specific spectroscopic results reported herein reveal that PEI adsorption and molecular ordering is influenced by both electrostatic and hydrophobic interactions. While the degree of PEI adsorption is stronger in the presence of anionic SDS than cationic DTAB, for both surfactants, PEI is molecularly disordered in acidic conditions and adopts a persistent net ordering as the solution pH becomes more basic. Both surfactants also display degrees of interfacial conformational ordering that is altered by the presence of the coadsorbed polymer. These results demonstrate the molecular-level diversity in PEI behavior at the droplet interface and provide insight into how such behavior can be controlled to yield nanocarrier technology with specific functions and enhanced efficacy.
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Affiliation(s)
- Emma Tran
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Andrew P Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
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34
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Carpenter AP, Altman RM, Tran E, Richmond GL. How Low Can You Go? Molecular Details of Low-Charge Nanoemulsion Surfaces. J Phys Chem B 2020; 124:4234-4245. [DOI: 10.1021/acs.jpcb.0c03293] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Andrew P. Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Rebecca M. Altman
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Emma Tran
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
| | - Geraldine L. Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon 97405, United States
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Zhao L, Zhu Z, Ma L, Li Y. O/W Nanoemulsion as an Adjuvant for an Inactivated H3N2 Influenza Vaccine: Based on Particle Properties and Mode of Carrying. Int J Nanomedicine 2020; 15:2071-2083. [PMID: 32273703 PMCID: PMC7104212 DOI: 10.2147/ijn.s232677] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 03/10/2020] [Indexed: 12/25/2022] Open
Abstract
Background and Purpose Adjuvant can reduce vaccine dosage and acquire better immune protection to the body, which helps to deal with the frequent outbreaks of influenza. Nanoemulsion adjuvants have been proved efficient, but the relationship between their key properties and the controlled release which greatly affects immune response is still unclear. The present work explores the role of factors such as particle size, the polydispersity index (PDI), stability and the safety of nanoemulsions by optimizing the water concentration, oil phase and modes of carrying, to explain the impact of those key factors above on adjuvant effect. Methods Isopropyl myristate (IPM), white oil, soybean oil, and grape-kernel oil were chosen as the oil phase to explore their roles in emulsion characteristics and the adjuvant effect. ICR mice were immunized with an emulsion-inactivated H3N2 split influenza vaccine mixture, to compare the nanoemulsion’s adjuvant with traditional aluminium hydroxide or complete Freund’s adjuvant. Results Particle size of all the nanoemulsion formed in our experiment ranged from 20 nm to 200 nm and did not change much when diluted with water, while the PDI decreased obviously, indicating that the particles tended to become more dispersive. Formulas with 80% or 85.6% water concentration showed significant higher HAI titer than aluminium hydroxide or complete Freund’s adjuvant, and adsorption rather than capsule mode showed higher antigen delivery efficiency. As mentioned about oil phase, G (IPM), F (white oil), H (soybean oil), and I (grape-kernel oil) showed a decreasing trend in their adjuvant efficiency, and nanoemulsion G was the best adjuvant with smaller and uniform particle size. Conclusion Emulsions with a smaller, uniform particle size had a better adjuvant effect, and the adsorption mode was generally more efficient than the capsule mode. The potential adjuvant order of the different oils was as follows: IPM > white oil > soybean oil > grape-kernel oil.
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Affiliation(s)
- Lanhua Zhao
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Kunming 650118, People's Republic of China.,Institute of Pathogenic Biology, School of Medicine, University of South China, Hengyang, 421001, People's Republic of China
| | - Zhe Zhu
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Kunming 650118, People's Republic of China
| | - Lei Ma
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Kunming 650118, People's Republic of China
| | - Yingbo Li
- Institute of Medical Biology, Chinese Academy of Medical Sciences, Peking Union Medical College, Kunming 650118, People's Republic of China
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36
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Kaur G, Chaudhary M, Jena KC, Singh N. Terbium(iii)-coated carbon quantum dots for the detection of clomipramine through aggregation-induced emission from the analyte. NEW J CHEM 2020. [DOI: 10.1039/d0nj01814g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
CQD-Tb: a selective chemosensor for detecting the antidepressant drug clomipramine in aqueous media.
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Affiliation(s)
- Gurpreet Kaur
- Post Graduate Department of Chemistry
- Sri Guru Gobind Singh College
- Chandigarh
- India
| | - Monika Chaudhary
- Centre for Biomedical Engineering
- Indian Institute of Technology Ropar
- Roopnagar
- India
| | - Kailash C. Jena
- Centre for Biomedical Engineering
- Indian Institute of Technology Ropar
- Roopnagar
- India
- Department of Physics
| | - Narinder Singh
- Department of Chemistry, Indian Institute of Technology Ropar
- Roopnagar
- India
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37
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Paiva F, Boromand A, Maia J, Secchi A, Calado V, Khani S. Interfacial aggregation of Janus rods in binary polymer blends and their effect on phase separation. J Chem Phys 2019; 151:114907. [PMID: 31542012 DOI: 10.1063/1.5100134] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Janus particles interfacially self-assemble into different structures when incorporated into multiphase systems. Dissipative particle dynamics simulations are employed herein to investigate the interplay between aggregation mechanisms and phase separation in polymer blends. Shorter rods with a standing configuration become increasingly "caged" or trapped in larger aggregates as weight fraction increases, which is reflected in the way that their diffusion is coupled to their aggregation rates. Janus rods of higher aspect ratios that are tilted at the interface aggregate side-by-side and are able to hinder phase separation kinetics. This is due to a combination of individual Janus rod conformations at the interface, their intrinsic aggregation mechanisms, aggregate fractal dimension, and aggregation rates, and can also be traced back to the scaling of the diffusion coefficient of aggregates with their size. Findings presented provide insight into the mechanisms governing two dimensionally growing colloidal aggregates at fluid interfaces, more specifically, those associated with Janus particles, and shed light on the potential of these systems in paving the way for designing new functional materials.
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Affiliation(s)
- F Paiva
- Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, USA
| | - A Boromand
- Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, USA
| | - J Maia
- Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, USA
| | - A Secchi
- Chemical Engineering Graduate Program (COPPE), Universidade Federal do Rio de Janeiro, Rua Horácio Macedo 2030, Cidade Universitária, Rio de Janeiro, RJ 21941-909, Brazil
| | - V Calado
- School of Chemistry, Universidade Federal do Rio de Janeiro, Rua Horácio Macedo 2030, Cidade Universitária, Rio de Janeiro, RJ 21941-909, Brazil
| | - S Khani
- Department of Macromolecular Science and Engineering, Case Western Reserve University, 2100 Adelbert Road, Cleveland, Ohio 44106, USA
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Baryiames CP, Teel M, Baiz CR. Interfacial H-Bond Dynamics in Reverse Micelles: The Role of Surfactant Heterogeneity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:11463-11470. [PMID: 31407910 DOI: 10.1021/acs.langmuir.9b01693] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Characterizing the hydrogen bond structure and dynamics at surfactant interfaces is essential for understanding how microscopic interactions translate to bulk microemulsion properties. Heterogeneous blends containing tens or hundreds of surfactants are common in the industry, but the most fundamental studies have been carried out on micelles composed of a single surfactant species. Therefore, the effect of surfactant heterogeneity on the interfacial structure and dynamics remains poorly understood. Here, we use ultrafast two-dimensional infrared spectroscopy and molecular dynamics simulations to characterize sub-picosecond solvation dynamics as a function of the surfactant composition in ∼120 nm water-in-oil reverse micelles. We probe the ester carbonyl vibrations of nonionic sorbitan surfactants, which are located precisely at the interface between the polar and nonpolar regions, and as such, report on the interfacial water dynamics. We show a 7% increase in hydrogen bond populations together with a 37% slowdown of interfacial hydrogen bond dynamics in heterogeneous mixtures containing hundreds of species, compared to more uniform compositions. Simulations, which are in semiquantitative agreement with experiments, indicate that structural diversity leads to decreased packing efficiency, which in turn drives water further into the otherwise hydrophobic region. Interestingly, this increase in hydration is accompanied by a slowdown of dynamics, indicating that water molecules solvating surfactants are conformationally constrained. These studies demonstrate that the composition and heterogeneity are key factors in determining interfacial properties.
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Affiliation(s)
| | - Morgan Teel
- University of Texas at Austin , Austin 78712 , Texas , United States
| | - Carlos R Baiz
- University of Texas at Austin , Austin 78712 , Texas , United States
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Qian Y, Deng GH, Lapp J, Rao Y. Interfaces of Gas-Aerosol Particles: Relative Humidity and Salt Concentration Effects. J Phys Chem A 2019; 123:6304-6312. [PMID: 31253043 DOI: 10.1021/acs.jpca.9b03896] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The growth of aerosol particles is intimately related to chemical reactions in the gas phase and particle phase and at gas-aerosol particle interfaces. While chemical reactions in gas and particle phases are well documented, there is very little information regarding interface-related reactions. The interface of gas-aerosol particles not only facilitates a physical channel for organic species to enter and exit but also provides a necessary lane for culturing chemical reactions. The physical and chemical properties of gas-particle interfaces have not been studied extensively, nor have the reactions occurring at the interfaces been well researched. This is mainly due to the fact that there is a lack of suitable in situ interface-sensitive analytical techniques for direct measurements of interfacial properties. The motivation behind this research is to understand how interfaces play a role in the growth of aerosol particles. We have developed in situ interface-specific second harmonic scattering to examine interfacial behaviors of molecules of aerosol particles under different relative humidity (RH) and salt concentrations. Both the relative humidity and salt concentration can change the particle size and the phase of the aerosol. RH not only varies the concentration of solutes inside aerosol particles but also changes interfacial hydration in local regions. Organic molecules were found to exhibit distinct behaviors at the interfaces and bulk on NaCl particles under different RH levels. Our quantitative analyses showed that the interfacial adsorption free energies remain unchanged while interfacial areas increase as the relative humidity increases. Furthermore, the surface tension of NaCl particles decreases as the RH increases. Our experimental findings from the novel nonlinear optical scattering technique stress the importance of interfacial water behaviors on aerosol particles in the atmosphere.
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Affiliation(s)
- Yuqin Qian
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Gang-Hua Deng
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Jordan Lapp
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Yi Rao
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
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Aminian A, ZareNezhad B. Oil-detachment from the calcium carbonate surfaces via the actions of surfactant, nanoparticle and low salinity brine: An insight from molecular dynamic simulation. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2019.03.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Surfactant-mediated enzymatic superactivity in water/ionic liquid mixtures, evaluated on a model hydrolytic reaction catalyzed by α-chymotrypsin. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.03.106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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42
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Carpenter AP, Tran E, Altman RM, Richmond GL. Formation and surface-stabilizing contributions to bare nanoemulsions created with negligible surface charge. Proc Natl Acad Sci U S A 2019; 116:9214-9219. [PMID: 31019075 PMCID: PMC6511027 DOI: 10.1073/pnas.1900802116] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The stabilization of nanoemulsions, nanosized oil droplets dispersed in water, is commonly achieved through the addition of surfactants and polymers. However, nanoemulsions in the absence of emulsifiers have been observed to acquire a significant negative charge at their surface, which ultimately contributes to their stability. While the source of this negative charge is disputed to this day, its presence is taken as an inherent property of the aqueous-hydrophobic interface. This report provides a look at the molecular structure and bonding characteristics of bare aqueous-hydrophobic nanoemulsion interfaces. We report the creation of bare nanoemulsions with near zero surface charge, which are marginally stable for several days. The process of creating these low-charge nanoemulsions (LCNEs) required rigorous cleaning procedures and proper solvent storage conditions. Using vibrational sum-frequency scattering spectroscopy, we measure the structure and bonding of the interfacial aqueous and hydrophobic phases. The surfaces of these LCNE samples possess a measurable free OH vibration, not found in previous studies and indicative of a clean interface. Tuning the nanoemulsion charge through addition of anionic surfactants, modeling potential surface-active contaminants, we observe the free OH to disappear and a reorientation of the interfacial hydrophobic molecules at micromolar surfactant concentrations. Notably, the free OH vibration provides evidence for stronger dispersion interactions between water molecules and the hydrophobic phase at the LCNE surface compared with similar planar water-alkane interfaces. We propose the stronger bonding interactions, in addition to an ordered interfacial aqueous layer, contribute to the delayed droplet coalescence and subsequent phase separation.
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Affiliation(s)
- Andrew P Carpenter
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403
| | - Emma Tran
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403
| | - Rebecca M Altman
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403
| | - Geraldine L Richmond
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR 97403
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Estabrook DA, Ennis AF, Day RA, Sletten EM. Controlling nanoemulsion surface chemistry with poly(2-oxazoline) amphiphiles. Chem Sci 2019; 10:3994-4003. [PMID: 31015940 PMCID: PMC6457192 DOI: 10.1039/c8sc05735d] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/26/2019] [Indexed: 12/12/2022] Open
Abstract
Emulsions are dynamic materials that have been extensively employed within pharmaceutical, food and cosmetic industries. However, their use beyond conventional applications has been hindered by difficulties in surface functionalization, and an inability to selectively control physicochemical properties. Here, we employ custom poly(2-oxazoline) block copolymers to overcome these limitations. We demonstrate that poly(2-oxazoline) copolymers can effectively stabilize nanoscale droplets of hydrocarbon and perfluorocarbon in water. The controlled living polymerization of poly(2-oxazoline)s allows for the incorporation of chemical handles into the surfactants such that covalent modification of the emulsion surface can be performed. Through post-emulsion modification of these new surfactants, we are able to access nanoemulsions with modified surface chemistries, yet consistent sizes. By decoupling size and surface charge, we explore structure-activity relationships involving the cellular uptake of nanoemulsions in both macrophage and non-macrophage cell lines. We conclude that the cellular uptake and cytotoxicity of poly(2-oxazoline)-stabilized droplets can be systematically tuned via chemical modification of emulsion surfaces.
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Affiliation(s)
- Daniel A Estabrook
- Department of Chemistry and Biochemistry , University of California , 607 Charles E. Young, Dr. E. , Los Angeles , CA 90095 , USA .
| | - Amanda F Ennis
- Department of Chemistry and Biochemistry , University of California , 607 Charles E. Young, Dr. E. , Los Angeles , CA 90095 , USA .
| | - Rachael A Day
- Department of Chemistry and Biochemistry , University of California , 607 Charles E. Young, Dr. E. , Los Angeles , CA 90095 , USA .
| | - Ellen M Sletten
- Department of Chemistry and Biochemistry , University of California , 607 Charles E. Young, Dr. E. , Los Angeles , CA 90095 , USA .
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Wilson CJ, Bommarius AS, Champion JA, Chernoff YO, Lynn DG, Paravastu AK, Liang C, Hsieh MC, Heemstra JM. Biomolecular Assemblies: Moving from Observation to Predictive Design. Chem Rev 2018; 118:11519-11574. [PMID: 30281290 PMCID: PMC6650774 DOI: 10.1021/acs.chemrev.8b00038] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Biomolecular assembly is a key driving force in nearly all life processes, providing structure, information storage, and communication within cells and at the whole organism level. These assembly processes rely on precise interactions between functional groups on nucleic acids, proteins, carbohydrates, and small molecules, and can be fine-tuned to span a range of time, length, and complexity scales. Recognizing the power of these motifs, researchers have sought to emulate and engineer biomolecular assemblies in the laboratory, with goals ranging from modulating cellular function to the creation of new polymeric materials. In most cases, engineering efforts are inspired or informed by understanding the structure and properties of naturally occurring assemblies, which has in turn fueled the development of predictive models that enable computational design of novel assemblies. This Review will focus on selected examples of protein assemblies, highlighting the story arc from initial discovery of an assembly, through initial engineering attempts, toward the ultimate goal of predictive design. The aim of this Review is to highlight areas where significant progress has been made, as well as to outline remaining challenges, as solving these challenges will be the key that unlocks the full power of biomolecules for advances in technology and medicine.
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Affiliation(s)
- Corey J. Wilson
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Andreas S. Bommarius
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Julie A. Champion
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Yury O. Chernoff
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Laboratory of Amyloid Biology & Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg 199034, Russia
| | - David G. Lynn
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Anant K. Paravastu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Chen Liang
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Ming-Chien Hsieh
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Jennifer M. Heemstra
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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Wiebenga-Sanford BP, Washington JB, Cosgrove B, Palomares EF, Vasquez DA, Rithner CD, Levinger NE. Sweet Confinement: Glucose and Carbohydrate Osmolytes in Reverse Micelles. J Phys Chem B 2018; 122:9555-9566. [DOI: 10.1021/acs.jpcb.8b07406] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Jack B. Washington
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Brett Cosgrove
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Eduardo F. Palomares
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Derrick A. Vasquez
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Christopher D. Rithner
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Nancy E. Levinger
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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Olenick LL, Troiano JM, Smolentsev N, Ohno PE, Roke S, Geiger FM. Polycation Interactions with Zwitterionic Phospholipid Monolayers on Oil Nanodroplet Suspensions in Water (D2O) Probed by Sum Frequency Scattering. J Phys Chem B 2018; 122:5049-5056. [DOI: 10.1021/acs.jpcb.8b00309] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Laura L. Olenick
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Julianne M. Troiano
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Nikolay Smolentsev
- 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
| | - Paul E. Ohno
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, 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
| | - Franz M. Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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Importance of Emulsification in Calibrating Infrared Spectroscopes for Analyzing Water Contamination in Used or In-Service Engine Oil. LUBRICANTS 2018. [DOI: 10.3390/lubricants6020035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Makarem M, Lee CM, Sawada D, O'Neill HM, Kim SH. Distinguishing Surface versus Bulk Hydroxyl Groups of Cellulose Nanocrystals Using Vibrational Sum Frequency Generation Spectroscopy. J Phys Chem Lett 2018; 9:70-75. [PMID: 29232139 DOI: 10.1021/acs.jpclett.7b02729] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In plant cell walls and cellulose-containing composites, nanocrystalline cellulose interacts with water molecules or matrix polymers through hydrogen bonding of the hydroxyl groups at the cellulose surface. These interactions play key roles in cellulose assembly in plant cell walls and mechanical properties of cellulose composites; however, they could not be studied properly due to the spectroscopic difficulty of selectively detecting the surface hydroxyl groups of nanocrystalline domains. This study employed the sum frequency scattering principle to distinguish the hydroxyl groups inside of the crystalline nanodomain of cellulose and those exposed at the surface of crystalline domains. The comparison of the spectra at various scattering angles revealed that the OH peak near ∼3450 cm-1 comes from the weakly hydrogen-bonded OH groups at the surface of crystalline cellulose. Also, a time delay measurement found that the sharp vibrational features observed near 3700 cm-1 can be attributed to isolated OH groups not accessible by ambient water molecules. These findings allow the distinction of surface versus bulk OH groups in sum frequency generation vibrational spectroscopy.
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Affiliation(s)
- Mohamadamin Makarem
- Department of Chemical Engineering, Materials Research Insitute, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Christopher M Lee
- Department of Chemical Engineering, Materials Research Insitute, Pennsylvania State University , University Park, Pennsylvania 16802, United States
| | - Daisuke Sawada
- Biology and Soft Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Hugh M O'Neill
- Biology and Soft Matter Division, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Seong H Kim
- Department of Chemical Engineering, Materials Research Insitute, Pennsylvania State University , University Park, Pennsylvania 16802, United States
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Development of triptolide-nanoemulsion gels for percutaneous administration: physicochemical, transport, pharmacokinetic and pharmacodynamic characteristics. J Nanobiotechnology 2017; 15:88. [PMID: 29202753 PMCID: PMC5715633 DOI: 10.1186/s12951-017-0323-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 11/25/2017] [Indexed: 12/24/2022] Open
Abstract
Background This work aimed to provide useful information on the use of nanoemulsions for the percutaneous administration of triptolide. Lipid nanosystems have great potential for transdermal drug delivery. Nanoemulsions and nanoemulsion gels were prepared to enhance percutaneous permeation. Microstructure and in vitro/in vivo percutaneous delivery characteristics of triptolide (TPL)-nanoemulsions and TPL-nanoemulsion gels were compared. The integrity of the nanoemulsions and nanoemulsion gels during transdermal delivery and its effects on the surface of skin were also investigated. The penetration mechanisms of nanoemulsions and nanoemulsion gels were investigated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). The transport characteristics of fluorescence-labelled nanoemulsions were probed using laser scanning confocal microscopy. A chronic dermatitis/eczema model in mice ears and the pharmacodynamic of the TPL-nanoemulsion gels were also investigated. Results Compared to TPL gels, significantly greater cumulative amounts of TPL-nanoemulsion gels and TPL-nanoemulsions penetrated rat skin in vitro. The in vivo microdialysis showed the concentration–time curve AUC0–t for TPL-NPs is bigger than the TPL-gels. At the same time, TPL-NPs had a larger effect on the surface of skin. By hydrating keratin and changing the structure of both the stratum corneum lipids and keratin, nanoemulsions and nanoemulsion gels influence skin to promote percutaneous drug penetration. Both hairfollicles and the stratum corneum are also important in this transdermal drug delivery system. Moderate and high dosages of the TPL-nanoemulsion gels can significantly improve the symptoms of dermatitis/eczema inflammation and edema erythematic in mice ears and can reduce the expression of IFN-γ and IL-4. Moreover, the TPL-nanoemulsion gels cause less gastrointestinal damage than that of the Tripterygium wilfordii oral tablet does. Conclusions Nanoemulsions could be suitable for transdermal stably releasing drugs and maintaining the effective drug concentration. The TPL-nanoemulsion gels provided higher percutaneous amounts than other carriers did. These findings suggest that nanoemulsion gels could be promising percutaneous carriers for TPL. The TPL-nanoemulsion gels have a significant treatment effect on dermatitis/eczema in the mice model and is expected to provide a new, low-toxicity and long-term preparation for the clinical treatment of dermatitis/eczema in transdermal drug delivery systems. Electronic supplementary material The online version of this article (10.1186/s12951-017-0323-0) contains supplementary material, which is available to authorized users.
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