Cross Linking and Rheological Characterization of Adsorbed Protein Layers at the Oil−Water Interface

Langmuir ◽  
2005 ◽  
Vol 21 (21) ◽  
pp. 9689-9697 ◽  
Author(s):  
Alexandre I. Romoscanu ◽  
Raffaele Mezzenga
Keyword(s):  
Cross Linking ◽  
Water Interface ◽  
Rheological Characterization ◽  
Adsorbed Protein ◽  
Oil Water

scholarly journals Toward Physicochemical and Rheological Characterization of Different Injectable Hyaluronic Acid Dermal Fillers Cross-Linked with Polyethylene Glycol Diglycidyl Ether

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 948
Author(s):  
Nicola Zerbinati ◽  
Sabrina Sommatis ◽  
Cristina Maccario ◽  
Maria Chiara Capillo ◽  
Giulia Grimaldi ◽  
...  
Keyword(s):  
Hyaluronic Acid ◽  
Polyethylene Glycol ◽  
Biological Activities ◽  
Diglycidyl Ether ◽  
Dermal Filler ◽  
Cross Linking ◽  
Matrix Structure ◽  
Dermal Fillers ◽  
Rheological Characterization

(1) Background: Injectable hyaluronic acid (HA) dermal fillers are used to restore volume, hydration and skin tone in aesthetic medicine. HA fillers differ from each other due to their cross-linking technologies, with the aim to increase mechanical and biological activities. One of the most recent and promising cross-linkers is polyethylene glycol diglycidyl ether (PEGDE), used by the company Matex Lab S.p.A., (Brindisi, Italy) to create the HA dermal filler PEGDE family. Over the last few years, several studies have been performed to investigate the biocompatibility and biodegradability of these formulations, but little information is available regarding their matrix structure, rheological and physicochemical properties related to their cross-linking technologies, the HA content or the degree of cross-linking. (2) Methods: Seven different injectable HA hydrogels were subjected to optical microscopic examination, cohesivity evaluation and rheological characterization in order to investigate their behavior. (3) Results: The analyzed cross-linked dermal fillers showed a fibrous “spiderweb-like” matrix structure, with each medical device presenting different and peculiar rheological features. Except for HA non cross-linked hydrogel 18 mg/mL, all showed an elastic and cohesive profile. (4) Conclusions: The comparative analysis with other literature works makes a preliminary characterization of these injectable medical devices possible.

Cross-Linking of Milk Proteins with Transglutaminase at the Oil−Water Interface

1997 ◽  
Vol 45 (7) ◽  
pp. 2514-2519 ◽  
Author(s):  
Merete Færgemand ◽  
Brent S. Murray ◽  
Eric Dickinson
Keyword(s):  
Milk Proteins ◽  
Cross Linking ◽  
Water Interface ◽  
Oil Water

scholarly journals Rheological Characterization of the Influence of Pomegranate Peel Extract Addition and Concentration in Chitosan and Gelatin Coatings

2021 ◽  
Vol 2 (3) ◽  
pp. 648-660
Author(s):  
Mirella Romanelli Vicente Bertolo ◽  
Rafael Leme ◽  
Virginia da Conceição Amaro Martins ◽  
Ana Maria de Guzzi Plepis ◽  
Stanislau Bogusz Junior
Keyword(s):  
Rheological Properties ◽  
Angular Frequency ◽  
Cross Linking ◽  
Rheological Characterization ◽  
Pomegranate Peel ◽  
All Solutions ◽  
Polymeric Solutions ◽  
Pomegranate Peel Extract ◽  
Peel Extract

In this study, the effects of an agro-industrial residue with active properties, pomegranate peel extract (PPE), were evaluated on the rheological properties of potential coatings based on chitosan (C) and gelatin (G). For this, rheological properties of the polymeric solutions were investigated in relation to PPE concentration (2 or 4 mg PPE g−1 solution), and to its incorporation order into the system (in C or in CG mixture). All solutions were more viscous than elastic (G″ > G′), and the change in PPE concentration had a greater influence accentuating the viscous character of the samples in which PPE was added to the CG mixture (CGPPE2 and CGPPE4). PPE addition to the CG mixture increased the angular frequency at the moduli crossover, indicating the formation of a more resistant polymeric network. This tendency was also observed in flow results, in which PPE addition decreased the pseudoplastic behavior of the solutions, due to a greater cross-linking between the polymers and the phenolic compounds. In general, all the studied solutions showed viscosities suitable for the proposed application, and it was possible to state the importance of standardizing the addition order of the components during the preparation of a coating.

Characterization of the microwave-induced boiling behaviour at oil/water interface

2020 ◽  
Vol 159 ◽  
pp. 120107
Author(s):  
Satoshi Sonobe ◽  
Yosuke Shibata ◽  
Yusuke Asakuma ◽  
Anita Hyde ◽  
Chi Phan
Keyword(s):  
Water Interface ◽  
Oil Water

Electrochemical characterization of an oil/water alternately wetted rotating cylinder electrode

CORROSION ◽  
10.5006/3638 ◽  
2020 ◽  
Author(s):  
Linxiao Zheng ◽  
Ziming Wang ◽  
Guang-Ling Song
Keyword(s):  
Rotating Cylinder ◽  
Water Interface ◽  
Current Waveform ◽  
Longitudinal Displacement ◽  
Flow Conditions ◽  
Rotating Cylinder Electrode ◽  
Electrochemical Current ◽  
Oil Water ◽  
Displacement Speed

To characterize the corrosion at oil/water interfaces, a vertically adjustable rotating cylinder electrode (VA-RCE) was developed based on the concept of “alternate wetting cell”, in which the electrochemical current reflecting the wet state of the RCE surface can be continuously monitored. Under a sinusoidal moving mode, the current waveform varied with the rotation rate and the longitudinal displacement speed or amplitude of the VA-RCE, implying that the dynamic wetting behavior of the VA-RCE surface in the oil/water interface region was influenced by the flow conditions; the replacement of oil phase by water phase became easier with increasing flow rate and alternating frequency of change between water wet and oil wet. The results also indicated that the wettability of the VA-RCE surface could be modified by the formation of corrosion products. All the results suggested that the VA-RCE could be used to quantitatively characterize the dynamic water/oil wetting state and the corrosion at an oil/water interface in a multiphase flow.

scholarly journals Stabilization of soybean oil by flaxseed gum and NMR characterization of its oil–water interface

2019 ◽  
Vol 17 (1) ◽  
pp. 892-899
Author(s):  
Mei-Qin Feng ◽  
Meng Wang ◽  
Jian Sun ◽  
Xing-Lian Xu ◽  
Guang-Hong Zhou
Keyword(s):  
Soybean Oil ◽  
Water Interface ◽  
Nmr Characterization ◽  
Oil Water ◽  
Flaxseed Gum

scholarly journals Characterization of Solids from Oilfield Emulsions

2005 ◽  
Vol 13 (6) ◽  
pp. 28-31
Author(s):  
Richard W. Cloud ◽  
Rebecca L. Ramsey ◽  
Robert A. Pultz ◽  
Michael K. Poindexter
Keyword(s):  
Crude Oil ◽  
Gas Evolution ◽  
Water Interface ◽  
Case Scenario ◽  
Pressure Drops ◽  
Liquid Phases ◽  
Oil Water ◽  
Water Gas ◽  
Oil Gas

Production of crude oil is generally accompanied by several other product phases, namely water, gas and solids. Pressure drops across chokes, concomitant gas evolution (due to pressure drops) and turbulence caused by various pipeline configurations can create difficult-to-resolve emulsions. Natural crude oil surfactants and solids exacerbate the problem further by migrating to the newly created oil-water interface and stabilizing the unwanted emulsions. Once the fluids arrive at the production facilities, a variety of vessels are employed to separate the oil, gas and water. Depending on the wettability of the solids, they will exit via one or both of the liquid phases. In a worse case scenario, the solids will accumulate at the oil-water interface.

THE ORIGIN, METABOLISM, AND STRUCTURE OF NORMAL HUMAN SERUM LIPOPROTEINS

1962 ◽  
Vol 40 (9) ◽  
pp. 1299-1326 ◽  
Author(s):  
F. A. Vandenheuvel
Keyword(s):  
Human Serum ◽  
Low Density Lipoproteins ◽  
Normal Human Serum ◽  
Low Density ◽  
Water Interface ◽  
Serum Lipoproteins ◽  
Adsorbed Protein ◽  
Normal Human ◽  
Oil Water ◽  
Film Balance

The main fractions obtained by ultracentrifugal separation of normal human serum lipoproteins form distinct classes. On the high-density side (d > 1.063) HDL1, HDL2, and HDL3; on the low-density side: LDL1, LDL2, and chylomicra are represented by particles of increasing density, lipid content, and diameter, the latter ranging from about 100 Å (HDL3) to about 15.000 Å (largest chylomicron).Distinctions between classes are evidenced by the action of solvents, the analysis of the N-terminal amino acids of peptides and immunochemical and metabolic properties.High-density lipoproteins (HDL) and low-density lipoproteins (LDL) form distinct groups displaying dissimilarities on the basis of many criteria. There can be little doubt that the origin, structure, and functions of the two groups are different. Among the LDL, LDL2, and LDL1 are both very similar and complex, LDL2 appearing to be a precursor of LDL1. HDL on the other hand may be partially derived from the chylomicra as a result of intravascular lipoprotein action upon some of these transient, very low-density lipoproteins with which they share characteristic peptides.Since no satisfactory structural model for the lipoproteins has yet been published, it was the purpose of this paper to re-examine all pertinent data and to present new speculations regarding these structures.It could be demonstrated that the lipoproteins on the low-density side are particles characterized by a protein coverage which is uniform over their extensive dimensional range and which corresponds to 36 A2 per amino acid residue. LDL1, the smallest of the group and the most abundant of the normal human serum lipoproteins, appears to consist of a single monolayer of lipids bearing adsorbed protein and surrounding a central core of occluded water. The general configuration of the adsorbed protein is still unknown. It is demonstrated that our present knowledge of the configuration of protein and synthetic polypeptide monolayers, most of which is derived from experiments with the film balance at air–water and petroleum ether – water (so-called oil–water) interface, cannot apply to these lipoproteins since there exists a considerable difference in physical and ionic topography between the experimental "oil–water" interface and the interface involved in lipoproteins.Part of the demonstration consists of the structural analysis of the lipid molecules involved. Diagrams representing these molecules, which are exact as to interatomic distances and bond angles are presented and used to explain the important phenomenon of sterol–phospholipid association. The latter is expected to play a considerable role in LDL1 (and presumably in the external lipid layer of LDL2 and chylomicra) where phospholipids and cholesterol (free and bound) represent 90% of the total molecular species with cholesterol (free and bound) accounting for two-thirds of them. By virtue of their associative properties, such molecules must exist in organized arrays conferring a directive influence to the lipid film on the configuration of the adsorbed protein. This should be quite different from the dispersive action of the disorganized petroleum ether layer in the so-called "oil–water" interface which induces partial random uncoiling of the protein chains.A demonstration of the method used in studying lipoprotein films by the use of diagrams is given. Its application to the cholesterol monolayer yielded for the limiting area a value in excellent agreement with that obtained with the film balance.

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