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  1. AU="Murphy, Bríd"
  2. AU="Tsuneyoshi, Isao"
  3. AU="Tram, Le Thi Hong"
  4. AU="Veli-Pekka Jaakola"
  5. AU="Erduğan, Hüseyin"

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  1. Artikel: Development of Hydroxyapatite Coatings for Orthopaedic Implants from Colloidal Solutions: Part 2-Detailed Characterisation of the Coatings and Their Growth Mechanism.

    Murphy, Bríd / Morris, Mick A / Baez, Jhonattan

    Nanomaterials (Basel, Switzerland)

    2023  Band 13, Heft 18

    Abstract: This study is the second part of a two-part study whereby supersaturated solutions of calcium and phosphate ions generate well-defined hydroxyapatite coatings for orthopaedic implants. An 'ideal' process solution is selected from Part 1, and the detailed ...

    Abstract This study is the second part of a two-part study whereby supersaturated solutions of calcium and phosphate ions generate well-defined hydroxyapatite coatings for orthopaedic implants. An 'ideal' process solution is selected from Part 1, and the detailed characterisation of films produced from this solution is undertaken here in Part 2. Analysis is presented on the hydroxyapatite produced, in both powder form and as a film upon titanium substrates representative of orthopaedic implants. From thermal analysis data, it is shown that there is bound and interstitial water present in the hydroxyapatite. Nuclear magnetic resonance data allow for the distinction between an amorphous and a crystalline component of the material. As hydroxyapatite coatings are generated, their growth mechanism is tracked across repeated process runs. A clear understanding of the growth mechanism is achieved though crystallinity and electron imaging data. Transmission electron imaging data support the proposed crystal growth and deposition mechanism. All of the data conclude that this process has a clear propensity to grow the hydroxyapatite phase of octacalcium phosphate. The investigation of the hydroxyapatite coating and its growth mechanism establish that a stable and reproducible process window has been identified. Precise control is achieved, leading to the successful formation of the desired hydroxyapatite films.
    Sprache Englisch
    Erscheinungsdatum 2023-09-21
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano13182606
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: Development of Hydroxyapatite Coatings for Orthopaedic Implants from Colloidal Solutions: Part 1-Effect of Solution Concentration and Deposition Kinetics.

    Murphy, Bríd / Morris, Mick A / Baez, Jhonattan

    Nanomaterials (Basel, Switzerland)

    2023  Band 13, Heft 18

    Abstract: This study introduces and explores the use of supersaturated solutions of calcium and phosphate ions to generate well-defined hydroxyapatite coatings for orthopaedic implants. The deposition of hydroxyapatite is conducted via several solutions of ... ...

    Abstract This study introduces and explores the use of supersaturated solutions of calcium and phosphate ions to generate well-defined hydroxyapatite coatings for orthopaedic implants. The deposition of hydroxyapatite is conducted via several solutions of metastable precursors that precipitate insoluble hydroxyapatite minerals at a substrate-solution interface. Solutions of this nature are intrinsically unstable, but this paper outlines process windows in terms of time, temperature, concentration and pH in which coating deposition is controlled via the stop/go reaction. To understand the kinetics of the deposition process, comparisons based on ionic strength, particle size, electron imaging, elemental analyses and mass of the formed coating for various deposition solutions are carried out. This comprehensive dataset enables the measurement of deposition kinetics and identification of an optimum solution and its reaction mechanism. This study has established stable and reproducible process windows, which are precisely controlled, leading to the successful formation of desired hydroxyapatite films. The data demonstrate that this process is a promising and highly repeatable method for forming hydroxyapatites with desirable thickness, morphology and chemical composition at low temperatures and low capital cost compared to the existing techniques.
    Sprache Englisch
    Erscheinungsdatum 2023-09-17
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano13182577
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel: Characterising Hydroxyapatite Deposited from Solution onto Novel Substrates: Growth Mechanism and Physical Properties.

    Murphy, Bríd / Baez, Jhonattan / Morris, Mick A

    Nanomaterials (Basel, Switzerland)

    2023  Band 13, Heft 17

    Abstract: Whilst titanium, stainless steel, and cobalt-chrome alloys are the most common materials for use in orthopaedic implant devices, there are significant advantages in moving to alternative non-metallic substrates. Substrates such as polymers may have ... ...

    Abstract Whilst titanium, stainless steel, and cobalt-chrome alloys are the most common materials for use in orthopaedic implant devices, there are significant advantages in moving to alternative non-metallic substrates. Substrates such as polymers may have advantageous mechanical biological properties whilst other substrates may bring unique capability. A key challenge in the use of non-metal products is producing substrates which can be modified to allow the formation of well-adhered hydroxyapatite films which promote osteointegration and have other beneficial properties. In this work, we aim to develop methodology for the growth of hydroxyapatite films on surfaces other than bulk metallic parts using a wet chemical coating process, and we provide a detailed characterisation of the coatings. In this study, hydroxyapatite is grown from saturated solutions onto thin titanium films and silicon substrates and compared to results from titanium alloy substrates. The coating process efficacy is shown to be dependent on substrate roughness, hydrophilicity, and activation. The mechanism of the hydroxyapatite growth is investigated in terms of initial attachment and morphological development using SEM and XPS analysis. XPS analysis reveals the exact chemical state of the hydroxyapatite compositional elements of Ca, P, and O. The characterisation of grown hydroxyapatite layers by XRD reveals that the hydroxyapatite forms from amorphous phases, displaying preferential crystal growth along the [002] direction, with TEM imagery confirming polycrystalline pockets amid an amorphous matrix. SEM-EDX and FTIR confirmed the presence of hydroxyapatite phases through elemental atomic weight percentages and bond assignment. All data are collated and reviewed for the different substrates. The results demonstrate that once hydroxyapatite seeds, it crystallises in the same manner as bulk titanium whether that be on a titanium or silicon substrate. These data suggest that a range of substrates may be coated using this facile hydroxyapatite deposition technique, just broadening the choice of substrate for a particular function.
    Sprache Englisch
    Erscheinungsdatum 2023-09-03
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article
    ZDB-ID 2662255-5
    ISSN 2079-4991
    ISSN 2079-4991
    DOI 10.3390/nano13172483
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Nano sized gallium oxide surface features for enhanced antimicrobial and osteo-integrative responses

    Murphy, Bríd / Martins, Carolina / Maggio, Mimma / Morris, Mick A. / Hoey, David A.

    Colloids and Surfaces B: Biointerfaces. 20232023 July 26, May 26, v. 227 p.113378-

    2023  

    Abstract: Gallium oxide has known beneficial osteo-integrative properties. This may have importance for improving the osteointegration of orthopedic implants. At high concentrations gallium is cytotoxic. Therefore, integration of gallium into implant devices must ... ...

    Abstract Gallium oxide has known beneficial osteo-integrative properties. This may have importance for improving the osteointegration of orthopedic implants. At high concentrations gallium is cytotoxic. Therefore, integration of gallium into implant devices must be carefully controlled to limit its concentration and release. A strategy based on surface doping of gallium although challenging seems an appropriate approach to limit dose amounts to minimize cytotoxicity and maximize osteointegration benefits. In this work we develop a novel form of patterned surface doping via a block copolymer-based surface chemistry that enables very low gallium content but enhanced osteointegration as proven by comprehensive bioassays. Polystyrene-b-poly 4vinyl pyridine (PS-b-P4VP) BCP (block copolymer) films were produced on surfaces. Selective infiltration of the BCP pattern with a gallium salt precursor solution and subsequent UV-ozone treatment produced a surface pattern of gallium oxide nanodots as evidenced by atomic force and scanning electron microscopy. A comprehensive study of the bioactivity was carried out, including antimicrobial and sterility testing, gallium ion release kinetics and the interaction with human marrow mesenchymal stomal cells and mononuclear cells. Comparing the data from osteogenesis media assay tests with osteoclastogenesis tests demonstrated the potential for the gallium oxide nanodot doping to improve osteointegration properties of a surface.
    Schlagwörter bone formation ; chemistry ; composite polymers ; cytotoxicity ; electron microscopy ; gallium ; humans ; nanotechnology ; orthopedics ; pyridines ; Block copolymer ; Nano-surface ; Osteogenesis ; Osteoclastogenesis
    Sprache Englisch
    Erscheinungsverlauf 2023-0526
    Erscheinungsort Elsevier B.V.
    Dokumenttyp Artikel ; Online
    Anmerkung Use and reproduction
    ZDB-ID 1500523-9
    ISSN 1873-4367 ; 0927-7765
    ISSN (online) 1873-4367
    ISSN 0927-7765
    DOI 10.1016/j.colsurfb.2023.113378
    Datenquelle NAL Katalog (AGRICOLA)

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  5. Artikel ; Online: Nano sized gallium oxide surface features for enhanced antimicrobial and osteo-integrative responses.

    Murphy, Bríd / Martins, Carolina / Maggio, Mimma / Morris, Mick A / Hoey, David A

    Colloids and surfaces. B, Biointerfaces

    2023  Band 227, Seite(n) 113378

    Abstract: Gallium oxide has known beneficial osteo-integrative properties. This may have importance for improving the osteointegration of orthopedic implants. At high concentrations gallium is cytotoxic. Therefore, integration of gallium into implant devices must ... ...

    Abstract Gallium oxide has known beneficial osteo-integrative properties. This may have importance for improving the osteointegration of orthopedic implants. At high concentrations gallium is cytotoxic. Therefore, integration of gallium into implant devices must be carefully controlled to limit its concentration and release. A strategy based on surface doping of gallium although challenging seems an appropriate approach to limit dose amounts to minimize cytotoxicity and maximize osteointegration benefits. In this work we develop a novel form of patterned surface doping via a block copolymer-based surface chemistry that enables very low gallium content but enhanced osteointegration as proven by comprehensive bioassays. Polystyrene-b-poly 4vinyl pyridine (PS-b-P4VP) BCP (block copolymer) films were produced on surfaces. Selective infiltration of the BCP pattern with a gallium salt precursor solution and subsequent UV-ozone treatment produced a surface pattern of gallium oxide nanodots as evidenced by atomic force and scanning electron microscopy. A comprehensive study of the bioactivity was carried out, including antimicrobial and sterility testing, gallium ion release kinetics and the interaction with human marrow mesenchymal stomal cells and mononuclear cells. Comparing the data from osteogenesis media assay tests with osteoclastogenesis tests demonstrated the potential for the gallium oxide nanodot doping to improve osteointegration properties of a surface.
    Mesh-Begriff(e) Humans ; Surface Properties ; Gallium/pharmacology ; Anti-Infective Agents ; Osteogenesis
    Chemische Substanzen gallium oxide (46F059V66A) ; Gallium (CH46OC8YV4) ; Anti-Infective Agents
    Sprache Englisch
    Erscheinungsdatum 2023-05-26
    Erscheinungsland Netherlands
    Dokumenttyp Journal Article
    ZDB-ID 1500523-9
    ISSN 1873-4367 ; 0927-7765
    ISSN (online) 1873-4367
    ISSN 0927-7765
    DOI 10.1016/j.colsurfb.2023.113378
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel: Fabrication of High-κ Dielectric Metal Oxide Films on Topographically Patterned Substrates: Polymer Brush-Mediated Depositions

    Yadav, Pravind / Gatensby, Riley / Prochukhan, Nadezda / C. Padmanabhan, Sibu / Davó-Quiñonero, Arantxa / Darragh, Philip / Senthamaraikannan, Ramsankar / Murphy, Bríd / Snelgrove, Matthew / McFeely, Caitlin / Singh, Sajan / Conway, Jim / O’Connor, Robert / McGlynn, Enda / Lundy, Ross / Morris, Michael A.

    ACS applied materials & interfaces. 2022 July 07, v. 14, no. 28

    2022  

    Abstract: Fabrication of ultrathin films of dielectric (with particular reference to materials with high dielectric constants) materials has significance in many advanced technological applications including hard protective coatings, sensors, and next-generation ... ...

    Abstract Fabrication of ultrathin films of dielectric (with particular reference to materials with high dielectric constants) materials has significance in many advanced technological applications including hard protective coatings, sensors, and next-generation logic devices. Current state-of-the-art in microelectronics for fabricating these thin films is a combination of atomic layer deposition and photolithography. As feature size decreases and aspect ratios increase, conformality of the films becomes paramount. Here, we show a polymer brush template-assisted deposition of highly conformal, ultrathin (sub 5 nm) high-κ dielectric metal oxide films (hafnium oxide and zirconium oxide) on topographically patterned silicon nitride substrates. This technique, using hydroxyl terminated poly-4-vinyl pyridine (P4VP-OH) as the polymer brush, allows for conformal deposition with uniform thickness along the trenches and sidewalls of the substrate. Metal salts are infiltrated into the grafted monolayer polymer brush films via solution deposition. Tailoring specific polymer interfacial chemistries for ion infiltration combined with subsequent oxygen plasma treatment enabled the fabrication of high-quality sub 5 nm metal oxide films.
    Schlagwörter hafnium ; oxygen ; polymers ; pyridines ; silicon nitride ; zirconium oxide
    Sprache Englisch
    Erscheinungsverlauf 2022-0707
    Umfang p. 32729-32737.
    Erscheinungsort American Chemical Society
    Dokumenttyp Artikel
    ISSN 1944-8252
    DOI 10.1021/acsami.2c07966
    Datenquelle NAL Katalog (AGRICOLA)

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  7. Artikel ; Online: Fabrication of High-κ Dielectric Metal Oxide Films on Topographically Patterned Substrates: Polymer Brush-Mediated Depositions.

    Yadav, Pravind / Gatensby, Riley / Prochukhan, Nadezda / C Padmanabhan, Sibu / Davó-Quiñonero, Arantxa / Darragh, Philip / Senthamaraikannan, Ramsankar / Murphy, Bríd / Snelgrove, Matthew / McFeely, Caitlin / Singh, Sajan / Conway, Jim / O'Connor, Robert / McGlynn, Enda / Lundy, Ross / Morris, Michael A

    ACS applied materials & interfaces

    2022  Band 14, Heft 28, Seite(n) 32729–32737

    Abstract: Fabrication of ultrathin films of dielectric (with particular reference to materials with high dielectric constants) materials has significance in many advanced technological applications including hard protective coatings, sensors, and next-generation ... ...

    Abstract Fabrication of ultrathin films of dielectric (with particular reference to materials with high dielectric constants) materials has significance in many advanced technological applications including hard protective coatings, sensors, and next-generation logic devices. Current state-of-the-art in microelectronics for fabricating these thin films is a combination of atomic layer deposition and photolithography. As feature size decreases and aspect ratios increase, conformality of the films becomes paramount. Here, we show a polymer brush template-assisted deposition of highly conformal, ultrathin (sub 5 nm) high-κ dielectric metal oxide films (hafnium oxide and zirconium oxide) on topographically patterned silicon nitride substrates. This technique, using hydroxyl terminated poly-4-vinyl pyridine (P4VP-OH) as the polymer brush, allows for conformal deposition with uniform thickness along the trenches and sidewalls of the substrate. Metal salts are infiltrated into the grafted monolayer polymer brush films via solution deposition. Tailoring specific polymer interfacial chemistries for ion infiltration combined with subsequent oxygen plasma treatment enabled the fabrication of high-quality sub 5 nm metal oxide films.
    Sprache Englisch
    Erscheinungsdatum 2022-07-07
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 1944-8252
    ISSN (online) 1944-8252
    DOI 10.1021/acsami.2c07966
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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