Advanced Functional and Structural Thin Films and Coatings: Multifunctional Biomaterials, Innovative Approaches to New Concepts and Applications II
Sponsored by: TMS Functional Materials Division, TMS: Thin Films and Interfaces Committee
Program Organizers: Adele Carrado, University of Strasbourg; Ramana Chintalapalle, University of Texas at El Paso; Gerald Ferblantier, University of Strasbourg - IUT LP / ICube Laboratory - CNRS; Nancy Michael, University of Texas at Arlington; Karine Mougin, Cnrs, Is2m; Heinz Palkowski, Clausthal University of Technology; Nuggehalli Ravindra, New Jersey Institute of Technology; Vikas Tomar, Purdue University
Thursday 8:30 AM
March 18, 2021
Room: RM 24
Location: TMS2021 Virtual
Session Chair: Adele Carrado, Université de Strasbourg IPCMS; Heinz Palkowski, IMET
8:30 AM Keynote
Diamond-like Coatings: A Flexible Platform for Multifunctional Antibacterial Coatings for Health: Linda Bonilla1; Pascale Chevallier1; Diego Mantovani1; 1Laval University
Diamond-like carbon (DLC) is a generic term that refers to at least seven forms of amorphous carbon materials, which vary depending on their sp3, sp2, and hydrogen content. These films display some of the unique properties of natural diamond and have consequently received considerable interest in the biomedical field. However, some challenges include their high compressive stress, which can cause adhesion and stability problems on commonly used metallic surfaces (SS316L). Moreover, DLC lacks some sought-after properties for biomedical applications, such as antibacterial activity. For these purposes, the creation of a carbide-metal interface as well as the incorporation of noble metals such as Ag have proven to regulate their intrinsic residual stress and enhance antibacterial activity. In this context, the main focus of this research is to create an ultra-stable, antibacterial and functional DLC coating doped with Ag/AgO on SS316L by means of a single-process low-pressure plasma treatment.
9:10 AM Invited
Grafting of Bioactive Polymers with Various Architectures for Preparing Antibacterial and Biocompatible Surfaces: Celine Falentin-Daudre1; Véronique Migonney1; 1LBPS-CSPBAT
Titanium (Ti) is widely used in orthopedic implants for its biocompatibility. Nevertheless and despite the prevention rules, 1,5% of implanted prostheses are still subject to bacterial infections. That’s the reason why chemical modification of titanium surfaces to confer desirable functional properties is required. Bioactive polymers such as poly(sodium styrene sulfonate) (polyNaSS) have good antibacterial properties and can improve osseointegration. In this context, we have developped 3 different techniques of polyNaSS covalent grafting onto Ti surfaces and study the influence of their architecture the in vitro biological responses of bacteria and osteoblasts. Two of them are “grafting from” techniques (thermal or UV irradiation approach). The third method is a “grafting to” technique involving an anchorage molecule onto which polyNaSS synthesized by RAFT polymerization is clicked. Overall outcomes of this investigation confirmed the significance of the sulfonate functional groups on the biological responses, regardless of the grafting method (Acta Biomaterialia, 2020).
9:40 AM
On the Controlled Antibacterial Activity of a Silver Oxide Doped Diamond-like Carbon Nanocoating With a Semi-permeable Polymeric Top Layer for Long-term Stability: Linda Bonilla1; Pascale Chevallier1; Diego Mantovani1; 1Laboratory for Biomaterials and Bioengineering, Laval University
Multi-functional antibacterial coatings are rapidly emerging as a key strategy to mitigate bacterial pathogens in healthcare settings. Amongst them, diamond-like carbon (DLC, i.e. hydrogenated amorphous carbon alloy) as a protective coating is particularly attractive due to its outstanding mechanical and tribological properties combined to chemical inertness and long-term stability. Moreover, the incorporation of AgO nanoparticles have proven to improve the antibacterial activity, whilst synergistically reducing the commonly known internal stress of DLC films. However, one of the main challenges of silver-based antibacterial coatings is to control the release of silver ions throughout an extended period of time. In this sense, additional polymeric top layers can act as rate-limiting barriers to sustain the antibacterial activity duration. Thus, this study presents a novel long-term stable and multi-functional AgO-DLC nanocoating on SS316L with an additional semi-permeable polymeric top layer by means of low-pressure plasma.
10:00 AM Keynote
Biomimetic Calcium-deficient Hydroxyapatite Coating on Activated Carbon Fiber Cloth: A Dual Drug Delivery System: Sylvie Bonnamy1; 1CNRS
A biomaterial able to control a drug release is highly desired for bone regeneration. Calcium-deficient hydroxyapatite (CDA) coatings deposited on activated carbon fiber cloth are produced by sono-electrodeposition process. The adsorption and desorption properties of each component and of the composite (CDA coating on carbon substrate) are studied, with the objective to develop a dual release biomaterial. For that, the adsorption and desorption of two drugs was investigated. One has a broad spectrum antibiotic (tetracycline), the other one is a nonsteroidal anti-inflammatory (aspirin). The results showed that drug adsorption and release depend on the adsorbent and the drug polarity/hydrophilicity. For the composite, two distinct modes of release are observed. In vitro biological tests showed an increase of the human osteoblasts viability on biomaterial with adequate drug adsorption. For in vivo tests, carbon/ apatite/aspirin materials implanted in bone defect performed on femur of rats showed an acceleration of bone regeneration.
10:40 AM
Design of Ti-copolymer Sandwiches for Biomedical Implant to Improve Formability: Flavien Mouillard; Patrick Masson1; Genevieve Pourroy1; Adele Carrado1; 1IPCMS - CNRS
Titanium (Ti) remains the most widely used metal in biomedical applications due to its biocompatibility. In particular, Ti-based plates are generally used to built-up craniofacial prosthesis and replace the bone. However, the significant difference of the mechanical properties between Ti and the surrounding tissues results in stress shielding which is detrimental for load bearing tissues. To attenuate this effect, a process with the elaboration of sandwiches materials was developed. In previous works, we aimed to employ surface-confined poly(methyl methacrylate) (PMMA) layers as adhesives to stick the polymer core (PMMA) on the metallic skins (Ti) to design resin-free sandwiches (SMS) by pressing the three components together above the glass transition temperature (Tg = 105°C) of the PMMA. To improve formability of the implants, a new strategy is proposed where the PMMA is replaced by a copolymer PMMA/PBMA (poly(butyl methacrylate)).
11:00 AM
Design of Innovative Hybrid Structures Using Grafting of Architecture-controlled Polymers for Biomedical Applications: Caroline Pereira1; Jean-Sébastien Baumann1; Patrick Masson2; Geneviève Pourroy2; Heinz Palkowsky3; Adele Carradò2; Véronique Migonney1; Céline Falentin-Daudré1; 1LBPS/CSPBAT, UMR CNRS 7244, Institut Galilée, Université Sorbonne Paris Nord; 2Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 CNRS, Université de Strasbourg; 3Clausthal University of Technology (TUC), IMET Institute of Metallurgy
Skull injuries caused by trauma and pathologies, such as tumor or congenital deformities, require the reconstruction of craniofacial prostheses. Titanium (Ti) is one of the most used materials for cranioplasty. However, this mono-material alone presents many drawbacks such as inappropriate mechanical properties compared to the bone. To solve this problem, the idea is to combine polymers and metals. Developing layered structures like sandwich materials composed of two metallic skin sheets and a copolymer core can be an interesting alternative to design innovative biomedical prostheses. To avoid Ti/Polymer/Ti structure’s delamination, we propose to chemically link polymer chains on metal surfaces by using the “grafting to” technique involving an anchorage molecule onto which the polymer synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization is clicked. Moreover, to confer antibacterial and osseointegration properties, a bioactive polymer such as poly(sodium styrene sulfonate) (polyNaSS) is grafted on the exterior surfaces of our sandwich.
11:20 AM
Forming Limits and Shaping of Ti-PMMA-Ti Sandwiches for Biomedical Applications: Gargi Shankar Nayak1; Heinz Palkowski1; 1TU Clausthal
Biocompatible sandwiches seem to be a viable option to overcome the “stress-shielding” problem between bone and implant. For developing such sandwiches, a processing route has been developed, starting with grafting of PMMA on Ti sheets. Grafting resulted in (optically) different zones on Ti sheets. Semi-finished Ti/PMMA/Ti sandwiches were prepared by hot pressing. The interpenetration between the grafted PMMA chains and PMMA sheet provided the necessary bonding strength. Comparable adhesion strengths were found for sandwiches for all the different grafted zones, suggesting a successful grafting of PMMA on large-scaled Ti sheets. The formability of (brittle at room temperature) PMMA was investigated by uniaxial, bending, and deep drawing tests under elevated temperatures, defining the ideal temperature for shaping the sandwiches to be just below the Tg of PMMA, where PMMA has sufficient plasticity with a low risk of delamination. The forming limits and conditions for such sandwiches will be introduced.