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Hongbo Zeng - One of the best experts on this subject based on the ideXlab platform.

  • Molecular interactions of mussel protective coating protein, mcfp-1, from Mytilus californianus
    'Elsevier BV', 2019
    Co-Authors: Ds Hwang, Yang Liu, Hongbo Zeng
    Abstract:

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (similar to 20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible Cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO3. Cohesion of mcfp-1 was gradually reduced with increasing the ionic Strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the Cohesion Strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the Cohesion. These results suggest that the Cohesion of mcfp-1 films is mainly mediated by cation-it interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (similar to 20 mol% of total amino acids of mcfp-1), and pi-pi interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating. (C) 2011 Elsevier Ltd. All rights reserved.X1146Nsciescopu

  • molecular interactions of mussel protective coating protein mcfp 1 from mytilus californianus
    Biomaterials, 2012
    Co-Authors: Dong Soo Hwang, Yang Liu, Hongbo Zeng
    Abstract:

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (~20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible Cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO(3). Cohesion of mcfp-1 was gradually reduced with increasing the ionic Strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the Cohesion Strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the Cohesion. These results suggest that the Cohesion of mcfp-1 films is mainly mediated by cation-π interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (~20 mol% of total amino acids of mcfp-1), and π-π interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating.

Senol Yilmaz - One of the best experts on this subject based on the ideXlab platform.

  • an evaluation of plasma sprayed coatings based on al2o3 and al2o3 13 wt tio2 with bond coat on pure titanium substrate
    Ceramics International, 2009
    Co-Authors: Senol Yilmaz
    Abstract:

    Abstract In this study, the effects of bond coat on the properties of Al 2 O 3 and Al 2 O 3 –13 wt.% TiO 2 coatings, which is plasma sprayed onto a commercial pure titanium substrate with and without Ni–5 wt.% Al (METCO 450 NS) as bond coating layer were investigated in terms of microhardness, bonding Strength and surface roughness. Optical and scanning electron microscopy (SEM) examinations revealed that there is a uniform coating layer with no spalling and delamination. However, there is a little amount of porosity. The results indicated that the application of bond coat layer in the plasma spraying of Al 2 O 3 and Al 2 O 3 –13 wt.% TiO 2 on pure titanium substrate has increased the hardness and bonding Strength of coatings. While the adhesive bonding is dominant without bond coat, the cohesive bonding is dominant with the application of the bond coating layer. It has been observed that percentage of Cohesion Strength was about three times higher than that of adhesion Strength.

  • the effect of bond coat on mechanical properties of plasma sprayed al2o3 and al2o3 13 wt tio2 coatings on aisi 316l stainless steel
    Vacuum, 2005
    Co-Authors: Senol Yilmaz, Mediha Ipek, Gozde F Celebi, Cuma Bindal
    Abstract:

    Abstract In this study, Al 2 O 3 and Al 2 O 3 –13 wt% TiO 2 were plasma sprayed onto AISI 316L stainless-steel substrate with and without Ni–5 wt% Al as bond coat layer. The coated specimens were characterized by optical microscopy, metallography and X-ray diffraction (XRD). Bonding Strength of coatings were evaluated in accordance with the ASTM C-633 method. It was observed that the dominant phase was Al 2 O 3 for both coatings. It was also found that the hardness of coating with bond coat was higher than that of coating without bond coat. Metallographic studies revealed that coating with bond coating has three different regions, which are the ceramic layer (Al 2 O 3 or Al 2 O 3 –13 wt% TiO 2 ), the bond coating, and matrix, which is not affected by coating. The coating performed by plasma-spray process without bond coating has two zones, the gray one indicating the ceramic layer and the white one characterizing the matrix. No delamination or spalling was observed in coatings. However, there are some pinholes in coating layer, but they are very rare. The bonding Strength of coatings with bond coat was higher than that of coating without bond coat. The Strength of adhesion and Cohesion was determined by means of a planemeter. It was seen that percentage of Cohesion Strength was higher than that of adhesion Strength.

Dong Soo Hwang - One of the best experts on this subject based on the ideXlab platform.

  • molecular interactions of mussel protective coating protein mcfp 1 from mytilus californianus
    Biomaterials, 2012
    Co-Authors: Dong Soo Hwang, Yang Liu, Hongbo Zeng
    Abstract:

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (~20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible Cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO(3). Cohesion of mcfp-1 was gradually reduced with increasing the ionic Strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the Cohesion Strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the Cohesion. These results suggest that the Cohesion of mcfp-1 films is mainly mediated by cation-π interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (~20 mol% of total amino acids of mcfp-1), and π-π interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating.

Yang Liu - One of the best experts on this subject based on the ideXlab platform.

  • Molecular interactions of mussel protective coating protein, mcfp-1, from Mytilus californianus
    'Elsevier BV', 2019
    Co-Authors: Ds Hwang, Yang Liu, Hongbo Zeng
    Abstract:

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (similar to 20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible Cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO3. Cohesion of mcfp-1 was gradually reduced with increasing the ionic Strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the Cohesion Strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the Cohesion. These results suggest that the Cohesion of mcfp-1 films is mainly mediated by cation-it interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (similar to 20 mol% of total amino acids of mcfp-1), and pi-pi interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating. (C) 2011 Elsevier Ltd. All rights reserved.X1146Nsciescopu

  • molecular interactions of mussel protective coating protein mcfp 1 from mytilus californianus
    Biomaterials, 2012
    Co-Authors: Dong Soo Hwang, Yang Liu, Hongbo Zeng
    Abstract:

    Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (~20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible Cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO(3). Cohesion of mcfp-1 was gradually reduced with increasing the ionic Strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the Cohesion Strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the Cohesion. These results suggest that the Cohesion of mcfp-1 films is mainly mediated by cation-π interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (~20 mol% of total amino acids of mcfp-1), and π-π interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating.

A Rodrigo - One of the best experts on this subject based on the ideXlab platform.

  • the correlation of scratch adhesion with composite hardness for tin coatings
    Surface & Coatings Technology, 2000
    Co-Authors: H Ichimura, A Rodrigo
    Abstract:

    Abstract The substrate hardness and coating thickness effects on the scratch adhesion of TiN coatings deposited on different substrates by arc evaporation and plasma assisted chemical vapor deposition are discussed from the point of view of the composite hardness. Experimental results show that the scratch hardness P s of all samples may be expressed as a function of the Vickers composite hardness as P s ≒0.7 H c for our condition. The critical loads L c for coatings of different thickness on various substrate materials prepared by the same deposition method are observed to be aligned on the same straight line of the L c – H c plots. The critical load increases proportionally to the product of the scratch depth and the composite hardness at the critical load. From optical microscope observation of the scratch channels and from the analysis of the acoustic emission signals, the lower critical load of PCVD coatings compared with arc-evaporated ones may be ascribed to the weak Cohesion Strength of the coating.