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1
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Effect of phospholipid and (phospho)lipase modification on interfacial properties of oil/water emulsion

100%
Wiącek A. E.
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
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2015
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vol. 70
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issue 1
EN
This review paper focused on the effect of typical phosphorlipid (or lecithin) and enzyme modification on electrokinetic parameters of oil/water emulsion. Physicochemical properties of the systems were investigated taking into account the effective diameter of the droplets as well as the zeta potentials using the dynamic light scattering technique. The effect of phospholipid and phospholipase modification on interfacial properties of o/w emulsion was examined as a function of temperature, pH and ionic strength (effect of Na+ or Ca2+ ions which occur in the physiological fluids). The particular role of Ca2+ ions in the dispersions with zwitterionic phospholipids (the main components of biological membrane) was confirmed.The phospholipids dipalmitoylphosphatidylcholine, DPPC or dioleoylphosphatidylcholine, DOPC having the same headgroup bound to the apolar tail composed of two saturated or unsaturated chains were used as stabilizing agents. The effective diameters do not always correlate with the zeta potentials. A possible reason for such behaviour might a mechanism different from the electrostatic stabilization. Phospholipids and their mixtures (e.g. lecithin) may undergo spontaneous aggregation in aqueous solution and selforganize into liposomes, which possess different sizes and surface affinities. These unique behaviours of phospholipid dispersion can be controlled using the investigated parameters. These findings are expected to increase in importance as phospholipid systems see more use in self-assembly applications.The other aim of the paper was the comparison of the enzyme phospholipase influence on lipid hydrolysis in the o/w emulsion environment. The work is the study which presents the twofold effect of ethanol dipoles on phosholipid hydrolysis. It is believed that the enzyme effect on the phospholipid aggregation behaviour at the oil-water interface will be helpful for understanding differentbiological phenomena.
2
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EFFECT OF CHITOSAN AND LIPID LAYERS DEPOSITED ONTO POLYETHYLENE TEREPHTHALATE (PET) ON ITS WETTING PROPERTIES

51%
Szafran K., Jurak M., Wiącek A. E.
Progress on Chemistry and Application of Chitin and its Derivatives
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2021
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vol. 26
210-221
EN
The wetting properties of chitosan (Ch) and single 1,2-dipalmitoylsn-glycero-3-phosphocholine (DPPC), cholesterol (Chol) and binary DPPC-Chol layers deposited onto polyethylene terephthalate activated by low-temperature air plasma (PETair) were examined. PET is widely used in tissue engineering, but its low hydrophilicity limits its integration with the surrounding tissues. Ch is a biocompatible polysaccharide, distinguished by its antimicrobial properties, widely distributed in medicine. DPPC and Chol are the major building components of cell membrane, so they can perfectly mimic membrane behaviour during contact with the Ch layer. Monolayers of lipids were deposited onto PETair with or without the Ch layer using the Langmuir-Blodgett technique. The total surface free energy (SFE) and its components changes were calculated from theoretical approaches. Wettability strongly depended on the monolayer composition as well as the Ch layer. The Ch film decreased the contact angle and increased SFE of the PET surface with the lipid monolayers due to specific organisation of molecules within the chitosan scaffold. The most promising combination of surface modification for tissue engineering applications seems to be the PETair/Ch/DPPC-Chol system.
3
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CHARACTERIZATION OF MIXED LANGMUIR MONOLAYERS OF CYCLOSPORINE A WITH THE PHOSPHOLIPID DPPC AT THE CHITOSAN SUBPHASE

51%
Woźniak K., Jurak M., Wiącek A. E.
Progress on Chemistry and Application of Chitin and its Derivatives
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2020
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vol. 25
227 - 235
EN
The properties of one-component and mixed monolayers of phospholipid 1,2–dipalmitoyl–sn–glycero–3–phosphocholine (DPPC) and polypeptide cyclosporine A (CsA) on the chitosan subphase were studied. DPPC is the main component that builds biological membranes, and CsA is an immunosuppressive drug typically used in medicine to prevent transplant rejections. The stability and reversibility of compression of these insoluble monolayers in the presence of chitosan (Ch) were examined by the Langmuir technique. The stability of the monolayers depended on the monolayer composition as well as the initial pressure (π0) of the relaxation process. The smallest changes in the relative pressure as a function of time were obtained at π0 = 10 mN/m. During compression–decompression cycles, the effect of chitosan was noticeable and caused isotherm shifts.
4
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WETTING PROPERTIES OF CHITOSAN-MODIFIED AND PLASMA-TREATED PEEK SURFACES

51%
Przykaza K., Jurak M., Wiącek A. E.
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EN
In this paper, the wettability of chitosan/phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine – DPPC), chitosan/lipid (cholesterol – Chol) and chitosan/protein (cyclosporine A – CsA) films on air plasma activated polyetheretherketone (PEEK) plates was studied. The layers were prepared using the solution spreading technique and their surface wetting properties were determined based on the measurements of the advancing and receding contact angles of water, formamide and diiodomethane. Moreover, based on the contact angle hysteresis model of Chibowski, values of total surface free energy were estimated. Significant changes in PEEK polarity were observed after plasma activation and modifications with Ch/DPPC, Ch/Chol and Ch/CsA layers. These molecules modulate the chitosan film surface by changing the type and magnitude of interactions, which is revealed in the values of surface free energy. These results may be important for the development and implementation of highly biocompatible bone substitution polymers coated with chitosan film with anti-fungal and anti-bactericidal properties. Those systems based on chitosan may also carry and release biologically active substances which could be relevant in the new generation of drug delivery systems.
5
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WETTABILITY OF CHITOSAN-MODIFIED AND LIPID/POLYPEPTIDE-COATED PEEK SURFACES

51%
Przykaza K., Woźniak K., Jurak M., Wiącek A. E.
Progress on Chemistry and Application of Chitin and its Derivatives
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2019
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vol. 24
172 - 182
EN
In the present paper, cold plasma-activated and chitosan-coated polyetheretherketone (PEEK) was covered with thin films of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, cholesterol, cyclosporine A, and their mixtures using the Langmuir-Blodgett technique. The thermodynamic function, i.e., surface free energy, of those systems was determined based on the contact angle hysteresis (CAH) approach. This parameter seems to be essential in determination of cell adhesion to polymeric materials and molecular interactions with living tissues. The obtained results show that the wettability and surface free energy of PEEK can be changed depending on the composition of the coating
6
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SURFACE CHARACTERISTICS OF DPPC MONOLAYERS DEPOSITED FROM TITANIUM DIOXIDE–CHITOSAN–HYALURONIC ACID SUBPHASES ON A GLASS SUPPORT

51%
Ładniak A., Jurak M., Wiącek A. E.
Progress on Chemistry and Application of Chitin and its Derivatives
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2019
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vol. 24
106 - 118
EN
The Langmuir-Blodgett technique was used to transfer the monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) from the subphase containing chitosan (Ch) and/or titanium(IV) oxide (TiO2) and/or hyaluronic acid (HA) on glass plates after a low-temperature air plasma treatment. The surface free energy and its components were determined on the basis of advancing and receding contact angle measurements of water (W), formamide (F), and diiodomethane (DM). To estimate the total surface free energy (𝛾𝑠𝑡𝑜𝑡), the contact angle hysteresis (CAH) model was used, and the obtained data were compared with the results calculated from the Lifshitz-van der Waals/acid–base (LWAB) approach. It was found that the subphase components modify the surface of the phospholipid monolayer by changing the type and magnitude of interactions. They were reflected as significant differences in the obtained values of total surface free energy and its components. These findings can help in the development of composite materials, thereby expanding the spectrum of applications for chitosan, TiO2, and HA, as well as understanding the interactions between biomaterial and cell.
7
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Wetting properties of phospholipid-polypeptide monolayers deposited onto polyethylene terephthalate

51%
Woźniak K. E., Jurak M., Wiącek A. E.
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
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2019
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vol. 74
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issue 2
EN
The paper presents changes in wettability of the unmodified and modified polyethylene terephthalate (PET) surfaces. A low temperature air plasma was used to activate the polymer surface and to change its hydrophilic–hydrophobic properties. Then, using the Langmuir-Blodgett technique, the Langmuir monolayers of 1,2–dipalmitoyl–sn–glycero–3–phosphocholine (DPPC) and cyclosporine A (CsA) with different molar fractions, i.e. χ=0.25, 0.50, 0.75, were deposited onto the activated PET surface. A series of DPPC and CsA monolayers was also transferred onto the PET-supported chitosan layer, previously produced by the dip-coating method. The wetting properties of such modified PET surfaces were then investigated by the contact angle measurements using three test liquids with well known surface tension components. The obtained results show that wettability depends on the composition of the deposited DPPC/CsA layer with or without chitosan. Presence of chitosan makes the DPPC/CsA film surface more polar due to specific organization of molecules that expose their polar heads outside.
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