Day :
- Biomaterials Applications | Properties of Biomaterials | Advanced Materials | 3D printing of Biomaterials | Biomaterials and Nanotechnology | Polymer Biomaterials
Session Introduction
Lucie Bacakova
Institute of Physiology of the Czech Academy of Sciences, Czech Republic
Title: How physical and chemical properties of the biomaterial surfaces govern the cell behavior– a review
Biography:
Lucie Bacakova, MD, PhD, Assoc. Prof. has graduated from the Faculty of General Medicine, Charles University, Prague, Czechoslovakia in 1984. She has completed her Ph.D at the age of 32 years from the Czechoslovak Academy of Sciences, and became Associated Professor at the 2nd Medical Faculty, Charles University. Since 2005, she is the Head of the Department of Biomaterials and Tissue Engineering, Institute of Physiology of the Czech Academy of Sciences. She is a specialist for studies on cell-biomaterial interaction and for vascular, bone and skin tissue engineering. She has published more than 160 papers in reputed journals (h-index 33).
Abstract:
Physical and chemical properties of the biomaterial surface, particularly its wettability, roughness and topography, mechanical properties and electrical activity, play a decisive role in the adhesion, growth and differentiation of cells. Earlier studies revealed that the adhesion and growth of cells is optimum on materials with moderate wettability, because on these surfaces, the adhesion-mediating proteins are adsorbed in almost physiological conformation, and are well-recognized by the cell adhesion receptors . As for the surface roughness and topography, a great attention has been paid to nanostructured surfaces. These surfaces mimic the Nano architecture of the native extracellular matrix and promote the cell adhesion and growth better than the conventional flat surfaces . Nano fibrous synthetic polymeric scaffolds proved as good substrates for adhesion and growth of dermal fibroblasts and keratinocytes, especially after coating with nanostructures of fibrin and collagen . After reinforcement with diamond or hydroxyapatite nanoparticles, these scaffolds improved the colonization with human bone marrow mesenchymal stem cells or human osteoblast-like cells . A higher biomaterial stiffness induced osteogenic cell differentiation, while softer substrates directed the cells towards myogenic or neurogenic phenotype . Electrical activity of biomaterials is another favorable factor influencing the cell behavior. In our earlier performed on thermally oxidized TiNb and Ti, positive charge enhanced proliferation of human osteoblast-like cells, while the negative charge enhanced their osteogenic differentiation . The adhesion, growth and osteogenic cell differentiation was also improved on ferroelectric substrates, such as LiNbO3 or BaTiO3. Therefore, modulation of physical and chemical properties of biomaterials is an effective tool for inducing the desired behavior of cells in construction of body implants and in tissue engineering.
Annett Dorner-Reisel
Schmalkalden University of Applied Sciences ,Germany
Title: 3D printing and characterisation of scaffolds for stem cells
Biography:
After a training as technician for ceramic processing in 1989 and studies in process and materials engineering, Annett Dorner-Reisel, worked as scientific staff. She received her PhD at the age of 27 years from TU Chemnitz (D). She specialized in biomaterials and hybrid structures for biomedical and functional materials for transportation and energy sector, i.e. sensor/actor applications or high performance carbon allotropes. Dr. Dorner-Reisel carried out postdoctoral studies at UC Santa Barbara, USA and Nagoya Institute of Research, Japanmailto:annettdornerreisel@web.de. Following second doctoral degree (Habilitation) at the age of 32 years at the Bergakademie Freiberg (D), she worked several years in industry before engaging 2011 in a professorship position at the Schmalkalden University HS SM. Since 2017, Prof. Dr.-Ing. habil. Dorner-Reisel is head of the research group “Bio-STEP” at HS SM, which clusters several researchers from different working directions like materials, production technology electronics and signal transfer. Bio-STEP focuses on biomaterials, biogenic materials for energy and light weight sectors, bionics and biomimetic.
Abstract:
Calcium phosphate (CaP) scaffolds are superiour materials for stem cell differentiation into bone cells. CaP materials are similar to the mineral component of natural bone, which favours stem cell differentiation into bone cells. Doping the calcium phosphates with suitable elements regulates protein and cell reactions further. In CaP, Mg2+ promotes angiogenesis, Sr2+ favor’s osteogenesis. Si4+ creates charge imbalance, if PO4 3- are replaced with SiO4 4- , which leads to a more electronegative surface. 3D printing is a method for CaP scaffold production offering excellent possibilities for control of macroscopic geometry, micro- and macroporosity, mechanical integrity as well as special demand for patient individual scaffold designs. Ceramic powders can be processed by several additive manufacturing methods. In the presentation, additive manufacturing of scaffold biomaterials is reviewed, shortly. Special information is given for CaP scaffold production by powder fuded printing (PFP) using hydroxyapatite powder. For successful and precise printing by the PFP, ceramic powders need to fulfil several requirements, like grain and agglomerate size distribution or chemical composition for demanded binder-powder interactions. In the present study, CO3 2- and flour substitution are proven by FT-IR and Raman spectroscopy. The microstructure of the 3D printed scaffolds is further characterised by X-ray diffraction before and after sintering. Special highlight of the study is first testing with additional lignin. Dissolved lignin was infiltrated into the porous structure of two different 3D printed geometries. Tests with ST-2 mouse cells confirm a slightly better biocompatibility in comparison to 3D printed scaffolds without lignin treatment.
Pascal Janvier
University of Nantes, France
Title: Assessment of analgesic effect from drug-loaded cements using cat walk gait analysis
Biography:
Pascal Janvier is currently assistant-professor at the University of Nantes (France) in the CEISAM laboratory. His research interests focus on phosphonate chemistry and biomaterials. He is the author of nearly 70 scientific articles, 7 patents, and is also co-founder of a company specializing in bone substitutes.
Abstract:
Postoperative pain following bone reconstruction is regarded as one of the major undesirable complications. This pain, which can become chronic, significantly disrupts patient recovery. However, the administration of local anesthetics has proven to be an effective analgesic technique for the treatment of postoperative pain with a significantly reduced drug use (e.g. morphine). In this clinical context, we proposed to evaluate the benefit in pain relief obtained with the defect filling by an injectable calcium phosphate cement (CPC) loaded or not with local anesthetics (bupivacaine or ropivacaine). Different formulations are prepared from a commercial CPC loaded with anesthetics. After their physicochemical characterizations, cements were implanted. Eighteen Wister female rats were operated with 0% (unloaded cement), 8% of bupivacaine and 8% ropivacaine, in a critical cylindrical defect in distal femur. To compare postoperative pain after bone filling surgery, a functional evaluation was performed using gait analysis with the Catwalk system.
K. Makasheva
Université de Toulouse, France
Title: Protein interaction with AgNPs-based plasma deposited nanocomposites: an excellent strategy to reveal the ‘protein-adsorption problem
Biography:
Kremena Makasheva is Researcher at CNRS, LAPLACE laboratory, Toulouse, France with a Ph.D. degree on Plasma Physics from Sofia University, Bulgaria, 2002, for her work on surface wave sustained plasmas. Her research activities in LAPLACE are directed to design and study of plasma deposited nanostructured materials for biomedical, optical and electrical engineering applications. She is the author and co-author of over 60 publications in international journals. Recently, she served as General Chair of the 11th IEEE Nanotechnology Materials and Devices Conference (IEEE NMDC 2016) in Toulouse.
Abstract:
Protein-adsorption problem’ on solid surfaces remains an active field of academic research due to its imoprtance for various industrial and biomedical applications representing the conditioning step of micro-organism adhesion and biofilm formation. Alternatively, nanomaterials and specifically nanocomposite thin layers became indispensable components in bioanalytical devices, since they clearly enhance their performances in terms of sensitivity and detection limits down to single molecules. However, rational engineering of the nanocomposites is mandatory in order to properly design their structural, optical and electrical properties. It thus opens the way for transition from material level of development to system level of applications.In this work we exploit the multifunctionality of silver nanoparticles (AgNPs) as plasmonic antenna when embedded at a controlled nanometric distance from the free surface of thin SiO2 layers (called plasmonic substrates) and as biocide agents because of their strong toxicity towards micro-organisms to study the ‘protein-adsorption problem’. The coupling of AgNPs and Discosoma red fluorescent proteins (DsRed), that displays exceptional photo-stability, is proposed as an appropriate strategy to study the ‘protein-adsorption problem’ on solid surfaces. To that end very thin DsRed protein layers were deposited on the plasmonic structures. The Raman spectra of the DsRed thin layers, not visible in absence of AgNPs, have been detected and analyzed owing to Surface Enhanced Raman Scattering (SERS). It was found that the DsRed proteins undergo conformational changes after adsorption on the plasmonic substrates. Three different DsRed chromophore configurations were identified and a scenario of the protein temporal evolution was proposed.
Frédéric Bossard
Institute of Engineering Univ. Grenoble Alpes ,France
Title: Bioscaff - structural and mechanical properties of electrospun scaffolds dedicated to soft tissue eingeneering
Biography:
Frederic Bossard has completed his PhD of Physics in 2001 from the Université de Bretagne Occidentale, France and a postdoctoral position at the ICEHT-FORTH of Patras, Greece in 2002. He joined the University of Grenoble in 2006 as associate professor and become full proffessor in 2012. Specialized in rheology and polymer processing, he is the secretary general of the French Group of Rheology. Since 2010, his research activity focuses on the development of biopolymer-based nanomaterials dedicated to tissue engineering and regenerative medicine applications.
Abstract:
Since the early 2000s, major efforts are being made to develop new scaffolds dedicated to cell growth for tissue regeneration but very few concern the reconstruction of soft tissues such as striated muscle, fibrous tissue, blood vessels or peripheral nervous system for instance. The major constraint on the reconstruction of such tissues is to give these supports simultaneously a bioresorbable character, a biomimetic structure and a mechanical behavior close to that of the tissue to regenerate. Such scaffolds must ensure the preservation of the mechanical properties but also allow the flow of biological fluids and therefore the transport of nutrients and cells that are essential for the process of cell growth and healing. The strategy adopted to reach this goal is to produce highly elastic scaffolds composed of nanofibers based on biodegradable and biocompatible polymers. Their mechanical properties are controlled both by the intrinsic property of the polymers and by the structure of the fibrous network.
New scaffolds made on polycaprolacton, PCL, and triblock copolymers with poly(lactic acid)s, PLAs, blocks separated by a Poly(ethylene glycol), PEG, block in the center were obtained. These polymers were electrospun in 3D nanofibrous structures. As illustrated in Fig. 1, we succeeded in structuring the non-woven mats that control their porosity by using structured collectors providing different regular and reproducible mesh. Their mechanical properties under tensile test have been characterized and a correlation with the deformation of the elementary cell of the structure is proposed.
Jomarien GarcÃa
Leiden University Medical Center , Netherlands
Title: Injectable thermosensitive hydrogel based on the physical mixing of Chitosan/Pluronic F127 as intraarticular drug delivery system
Biography:
Jomarien García has completed her Bachelor’s degree in Pharmaceutical Sciences at the University of Havana in 2006 and her Master degree in Chemistry in the Faculty of chemistry of the same university in 2011. She is assitant's researcher in the Polymeric Biomaterials department at the Biomaterials Center. She is doing her PhD in Translational Nanobiomaterials and Imaging group, Radiology department at the Leiden University Medical Center (LUMC). She has presented more than 20 comunications in Internationals Scientific Congresses and has published more than 5 scientific articles
Abstract:
Knee osteoarthritis (OA) is a disease characterized mainly by cartilage degradation, which produce pain, stiffness, and loss of motion in the joint. Pharmacologycal therapy of this disorder is directed towards pain and inflammation. Non-steroidal and steroidal anti-inflammatory substances are the most frequently used agents. Nevertheless, the oral or systemic administration of such drugs is hindered by numerous side effects, which could be overcome by their intra-articular (IA) administration. The aim of this work was to evaluate the behavior of dexamethasone sodium phosphate (DMT) release from thermosensitive hydrogels based on the physical mixing of Chitosan/Pluronic F127 (CS/PF) as an IA drug delivery system. For the preparation of hydrogels, chitosan (1% w/v) and pluronic (20, 25, 30% w/v) were mixed. Formulation with 25% of pluronic (CS/PF-25) was selected for several assays. Scanning electron microscopy analysis indicated that the CS/PF-25 hydrogels exhibited a low porous structures. Infrared spectroscopy analysis indicated the main functional groups of each component of the hydrogel. The cytotoxicity and cell viability of the hydrogels were assessed by MTS and LIVE/DEAD® assays, where the results demonstrated non-cytotoxic effect of the hydrogel on the human chondrocyte cell culture (C-28). DMT was mixed with CS/PF-25 hydrogel at the concentration of 2 mg/mL concentration, in vitro release study showed that there is no initial burst of drug and 50% of DP was delivered in 72 hours. This study suggests the potential of CS/PF-25 gel as an injectable carrier for future applications of delivering therapeutics for the knee osteoarthritis treatment
J.-W. Park
Kyungpook National University School of Dentistry, Korea
Title: Immediate Blood Platelet Response Modulated by Surface Chemistry Alteration and Nano-topography in Titanium Implant Surface
Biography:
Jin-Woo Park has completed his dual PhD from Tokyo Medical & Dental University (Japan) and Chonnam National University (Korea). He is department head of Periodontics of Kyungpook National Univeristy School of Dentistry and Dental Hosipital, Korea. He has published more than 100 papers in reputed journals.
Abstract:
Surface nano-topography and chemistry alteration are important in the current modification of titanium (Ti) bone implants. Studies have shown that blood platelet response to modified Ti implant surface influences subsequent biological events and ultimate implant bone healing. This study investigated whether the addition of bioactive ions (in this study, Ca) exerts a beneficial effect on immediate platelet activation in a nanostructured Ti implant surface. Results indicate that surface nano-topographical modification positively affects immediate platelet response and surface Ca ion modification further promotes platelet activation. Surface Ca modification increased fibrin network formation and growth factor release (PDGF-AB) in the nanostructured Ti surface. These findings suggest that nano-topographical and chemical surface modification positively modulate immediate blood platelet response to Ti bone implants. Enhanced immediate blood platelet activation seems to be one of important underlying mechanisms for rapid bone healing capacity of surface Ca-modified nanostructured Ti implants.
Behnam Dashtbozorg
University of Birmingham, United Kingdom
Title: Plasma nitriding and femtosecond LIPSS texturing for durable antibacterial surfaces
Biography:
Behnam Dashtbozorg is a third year PhD student with the Innovative Metal Processing (IMPaCT) centre for doctoral training (CDT). He is based at the Metallurgy and Materials groups at the University of Birmingham.. His work involves the use of novel triple-glow plasma treatments on austenitic stainless steel materials in order to produce durable antibcacterial stainless steel surfaces for use in food and medical industries. Additionally, he is also looking at combining laser texturing and plasma surface engineering for the production of long lasting multi-functional surfaces.
Abstract:
Development of wear resistant, anti-biofouling and highly biocompatible surfaces presents a great challenge in the food and medical industry. Owing to their excellent corrosion resistance and low cell toxicity, austenitic stainless steels have found widespread applications in these areas. However, as a result of their poor wear resistance, surface treatments are typically necessary. One common way this is addressed is through low temperature plasma nitriding to form the S phase. In addition to improving the hardness, the S-phase also retains the corrosion resistance of the stainless steel bulk. Although this resolves many of the mechanical issues with the use of stainless steels, it does not improve their susceptibility to bacterial attachment and growth. Consequently, bactericidal elements (bacteria killing) or anti-biofouling measures (stopping attachment & growth) have to be utilised to counteract this issue. Femtosecond laser induced periodic surface structures (f-LIPSS) are known for producing self-organised bacteria resistant patterns through material ablation. However, due to the link between the anti-biofouling properties and the pattern integrity it becomes vital to preserve the textures for as long as possible. In this study it is hoped that by combining f-LIPSS pattern with active screen plasma nitriding it will be possible to produce durable and long lasting antibacterial surfaces.
Sukhvir Kaur Bhangu
University of Melbourne, Australia
Title: Ultrasonic transformation of tannic acid into bio functional ellagic acid micro/nano crystals with distinct morphologies
Biography:
Sukhvir Kaur Bhangu is currently pursuing final year of my PhD from University of Melbourne in School of chemistry. She working on ultarsonically generated nanoparticles from different polyphenols, amino acids and others biomolecules and then to study their biomedical applications.
Abstract:
Acoustic cavitation bubbles can be used to perform miscellaneous reactions due to their reactive surface. A simple ultrasonic approach has been developed for synthesizing crystalline, regularly shaped ellagic acid particles from amorphous tannic acid. Multiple and consecutive reactions have been performed on tannin molecules, including, hydrolysis of an ester linkage, C-C coupling reactions, condensation reaction and crystallization without the addition of any external reagent. The size and shape of these crystals could be finely controlled by choosing appropriate ultrasonic parameters such as sonication time, power and frequency. The formation of ellagic acid was confirmed by absorption spectroscopy, ellagic acid assay, HPLC, mass spectrometry and XRD. The synthesized particles showed blue, green and red emissions, high thermostability, antioxidant properties and a remarkable antiproliferative effect in human breast adenocar-cinoma cells. The particles were also used to load anticancer drugs such as doxorubicin and 80% of drug loading efficiency was observed in 24 h.
Biography:
Olcay Ozcan has completed academic bridge program on Ualberta is a top 5 Canadian university and one of the top 100 in the world and took one year BSc degree from University of Alberta and besides presently undergradute student at department of metarials and metalurgy engineering in Marmara University.
Abstract:
Co-based alloys (Co-212) have been used in biomedical application for implant materials because of promising as a potential material for biomedical applications. This paper describes the effect of sintering conditions on microstructural, mechanical, and electrochemical properties of injection molded for Co-based superalloy. Co-212 powders were injection molded with wax-based binder. The critical powder loading for injection molding was 60 vol.%. Binder debinding was performed in solvent and thermal method under high purity argon atmosphere. After debinding, the samples were sintered at different temperatures and times in vacuum. The densities of the sintered components were determined in accordance with the Archimedes' principle. A correlation between sintering temperature and time which bring about high densification and good corrosion resistance was obtained. Results of study showed that injection molded Co-based alloys exhibited high mechanical and corrosion properties in a physiological environment. Maximum density and hardness were obtained for maximum sintering temperatures and times.
Dongkyu Koo
KIST School, University of Science and Technology, Korea
Title: Enhanced corrosion resistance of biodegradable magnesium using coenzyme
Biography:
Dongkyu Koo in 2014 obtained Bachelor’s degree at the Faculty of Applied chemistry and biotechnology, AJOU University in Korea. Currently he is working a researcher at the U&i company which making bio-medical applications in Korea and studying for Master’s degree at University of Science and Technology at the same time. Main field of his interests is surface treatments of metal-based materials for orthopaedic implants; electro-polishing, polymer and bio-chemical coatings.
Abstract:
Magnesium is essential element in human body and one of the lightest metals, exhibiting good mechanical properties. Recently, there has been a tremendous increase in studies on the development of magnesium implant due to its unique biodegradable property that could reduce the burden of subsequent surgery.However, magnesium has a rapid degradation especially in aggressive chloride environments like body fluid.Accelerated degradation of magnesium can cause the loss of mechanical integrity in a short period which can limit its application as an implant material.Moreover, high amount of hydrogen gas is generated by relatively severe corrosion rates of magnesium. It contributes to the causes of swelling of skin and causes consequent inflammation of soft tissue where is directly in contact with implants. Therefore, there is still concern about the safety of the using biodegradable magnesium alloys.In this study, we analyzed the influence of coenzyme on corrosion behavior of magnesium. The analysis of corrosion rate was held by using Hanks’ balanced salt solution (HBSS) as a simulated body fluid and in condition of 37℃. Thus, with deferring the concentration of the coenzyme used in this study, corrosion rates decreased by 40% in immersion tests. Also, comparable results were obtained in electrochemical tests. Results showed that hydrogen gas produced from corrosion of magnesium can be controlled.
Yaima Campos Mora
Havana University, Cuba
Title: A novel porous multilayer Scaffold for cartilage tissue engineering
Biography:
Yaima Campos has finished her Bachelor’s Degree in the Chemistry Faculty of Havana University, Cuba (2005). The researcher has completed her Master Degree in Science and Technology of Materials, “Obtaining and characterization of acrylic composites loaded with hydroxyapatite for their possible use in bone restoration” in the Institute of Materials Science and Technology, Cuba (2010). In this moment, she is doing her PhD in the Translational Nanobiomaterials and Imaging group of Radiology Department, in Leiden University Medical Center (LUMC), Netherlands. She has participated in 23 International Scientific Congress and has published more than 10 scientific articles.
Abstract:
Biomaterials for cartilage tissue engineering has been widely used in recent years because techniques for treating cartilage affections, together with palliative treatments, have not been effective so far. For that reason, this research is aimed to obtain and characterize a new porous multilayer scaffolds based on natural polymers for their potential use in a possible cartilage regeneration and restoration. The surface morphology of chitosan/collagen materials (with hydroxyapatite in the calcified layer) was characterized by Scanning Electron Microscopy (SEM) showing an adequate porosity able to allow the nutrients exchange and cell movility through the matrix. In vitro studies of cell viability and proliferation were carried out with human C-28 chondrocyte cell line, by MTS and Live/Dead assays. The specimens allowed cell viability and proliferation in a period of 14 days, showing that scaffolds were non cytotoxic. The bioactive behavior of the calcified layer was also evaluated by immersing materials in a Simulated Biological fluid (SBF) solution for a period of 28 days. The specimens were analyzed by SEM at 3, 7, 14 and 28 days of immersion in solution. Some apatite nuclei were observed on the surface after 3 days, a higher population of nuclei at 14 days and an apatite layer covering almost the entire surface at 28 days. This fact guarantees the osseointegration of scaffolds with subchondral bone. The results obtained are encoring, proposing this porous multilayer scaffolds as a promising candidates for cartilage tissue engineering.
Šuliková Michaela.
Safarik University in Kosice, Slovak Republic
Title: Ti-Si biocompatible materials for orthopedics applications
Biography:
Šuliková M is studying her second year of PhD at the Faculty of Science at the Pavol Jozef Šafárik University in Košice, Department of Condensed Matter Physics. She graduated in physics and biology and completed her Master’s degree at the P. J. Šafárik University in Košice. She has 5 publications. Now she is studying new type of biocompatible alloys. Her first results were presented at ISMANAM 2017 in the form of a poster. Now, her results will be presented at 4th Annual Conference on Biomaterials.
Abstract:
Titanium alloys are widely used in biomedical applications because of their higher biocompatibility, excellent corrosion resistance, low elastic modulus in comparison to other metallic biomaterials. However, they commonly contain aluminium, vanadium, chromium, cobalt, manganese etc., which ions cause damage human tissues. We decided to develop a low-density alloy with a high hardness that will be biocompatible and cost-effective.Ti and Si are biocompatible elements, moreover Si support bone calcification. We prepared and characterize five Ti-Si alloys. One of the five is monophase alloy, consisting of sole Ti5Si3. Microstructure was examined by synchrotron X-rays diffraction and high resolution transmission electron microscopy. This alloy is almost 300% harder compared the implants used, today. Mass density of the alloy is 4.27 g/cm3, while modulus of elasticity is 187 GPa. All Ti-Si alloys are biocompatible asertaineded in respect to MC3T3E1 mouse preosteoblastic cells. In the poster I will present preparation, phase composition, microstructure morphology, biocompatibility and basics mechanical properties of five Ti-Si intermetallic alloys.
Jeasung Park
Korea Institute of Industrial Technology, korea
Title: Synthesis and cross-linking of hydrogen and vinyl dimethicones for artificial secondary skin
Biography:
In Park has completed his PhD from Michigan State University and postdoctoral studies from Cornell University. He is a principal researcher of Korea Institute of Industrial Technology, a government-funded institute and a full professor of University of Science and Technology in Korea as well. He has published 26 research papers in journals and more than 30 domestic/international patents.
Abstract:
We report the synthesis and application of cross-linked silicones between hydrogen and vinyl dimethicones which are base materials for artificial secondary skin in order to hide old and wrinkled skin. Hydrogen dimethicones were synthesized by ring-opening polymerization of 1,1,3,3,5,5,7,7-octamethylcyclotetrasiloxane (D4) and 1,3,5,7-tetramethylcyclotetrasiloxane (D4H) in the presence of trifric acid as an acidic catalyst and hexamethyldisiloxane as an end capping agent. The initial molar ratios of D4 and D4H before reaction were 50:50, 70:30, 80:20 and 90:10 and the resulting molar ratios ended up with 55:45, 75:25, 85:15 and 94:6, respectively, confirmed by 1H-NMR. Gel permeation chromatography results showed that the polymers are monodispersed with ~1.8 PDI. Vinyl termainated dimethicones were also prepared by functionalization of dihydroxyl terminated dimethicones which had been synthiszed from octamethylcyclotetrasiloxane through ring-opening polymerization. The vinyl functionalization was performed in the presence of dichloromethane as a solvent and dimethylvinylcholorosilane as a vinyl end capping agent. The final products exhibited 11,300-13,500 of Mn, 38,900-67,900 of Mw and 3,43-5.03 of PDI values, which are depending on the molar amount of H2O. Cross-linked silicone materials for artificial secondary skins were fabricated by mixing the hydrogen and the vinyl dimthicones with Karstedt catalyst. Their tensile modulus and toughness are not sufficiently high for artificial skin application. In order to improve the mechanical properties, a fumed silica (Aerosil 200, 2.5 part based on the weight of the dimethicone mixture) was added to dimethicone mixture before adding the cross-linking catalyst. The tensile modulus and the elongation were enhanced by approximately 5-fold and 2-fold, respectively.
Ali Deniz Dalgic
Middle East Technical University,Turkey
Title: Graphene oxide incorporated silicate doped nano-hydroxyapatite novel composite for bone tissue engineering
Biography:
Ali Deniz Dalgic has completed his undergraduate study in Department of Biological Sciences and his MSc in Department of Engineering Sciences from Middle East Technical University. During his MSc, he studied on liposomes as controlled drug delivery system for cancer therapy. He is a PhD candidate in Middle East Technical University, Department of Engineering Sciences. In his PhD studies, besides liposomal drug delivery, he has also specialized on tissue engineering and regenerative medicine. He has 6 years of working experience as a research and teaching assistant. He has 2 published and 1 accepted journal articles and has ongoing projects on drug delivery systems, tendon and bone tissue engineering.
Abstract:
Hydroxyapatite, as the natural inorganic phase of the bone tissue has been widely used as the main structure of bone tissue scaffolds. In studies, ion substitution into hydroxyapatite structure enhanced the osteogenic properties. Silicon is an ion that was used to produce silicate doped hydroxyapatite (SiHA). SiHA is reported to promote proliferation and osteogenic activity of osteoblasts. Graphene oxide (GO) is formed by functionalization of graphene with oxygen-containing groups, reported to enhance adhesion and growth of cells while inducing calcium phosphate deposition. In this study, we aimed to combine osteogenic properties of SiHA and GO in order to produce a novel composite to be incorporated into bone scaffolds as osteogenic component. Therefore, composite groups with different ratios of SiHA and GO were compared to identify the most effective composite composition. Composite groups were evaluated in a fibrous scaffold structure formed by electrospinning within PCL solution. Scaffolds were characterized in terms of protein adsorption-desorption, calcium deposition and tensile strength properties. In vitro studies were conducted with human osteosarcoma (Saos-2) cell line as cell adhesion, spreading, proliferation and ALP activity. Scaffold groups bearing GO showed increased protein adsorption and improved initial cell attachment. Cell spreading and proliferation were highest in the group with effective concentrations of SiHA and GO (PCL-10%SiHA-4%GO). The group also showed higher calcium phosphate deposition and alkaline phosphatase activity. Results showed that the novel GO incorporated SiHA composite has high potential to be used as a bone tissue engineering material.
Deniz Atila
Middle East Technical University, Turkey
Title: Pullulan hydrogel-immobilized bacterial cellulose membranes for wound dressing
Biography:
Deniz Atila has completed MSc degree at the age of 26 in Department of Engineering Sciences from Middle East Technical University and has been working on PhD studies in the same department and has published 3 papers in reputed journals.
Abstract:
When a full-thickness skin is lost due to trauma or diseases, wound bed can not be immediately repaired. Coverage of damaged tissue with a material other than patient’s own skin to prevent dehydration and infection can be an alternative. Thus, bilayer membranes may be candidates for satisfying requirements of top and sub layers of a potential wound dress. For instance, top layer should be dense and strong whereas sub layer should be porous and cyto compatible. Moreover, both layers should have high-water-absorbing capability. Membranes composed of bacterial cellulose (BC) produced by Acetobacter species have been widely utilized for different purposes owing to its excellent mechanical properties and pronounced water retention capacity. Pullulan (PUL) is another extracellular polysaccharide produced by Aureobasidium species possessing water solubility and gelation ability. Therefore, a membrane system composed of these materials can be formed by crosslinking PUL and attaching it onto BC layer to prevent delamination. Actually, PUL can effectively be immobilized on BC since it adheres to cellulose in nature. In this study, BC/PUL bilayer membranes were fabricated as a wound dressing composite for the first time in a simple and practical manner. BC produced by bacteria was purified and used in original form. PUL solution (20(w/v)%) was prepared in distilled water including trisodium trimetaphosphate (STMP) as a ‘green’ crosslinking agent (STMP/PUL(w/w):1/3) and NaOH was added into the PUL solution (NaOH/STMP(w/w):1/10) as an initiator prior to pouring the solution onto BC membranes. Crosslinking occurred within 12min. Optimizations for manufacturing membranes were completed and characterizations are under study.
Miriela Tomás
Company Laboratories AICA, Havana, Cuba
Title: Preparation and in vitro evaluation of chitosan/apatite composite for bone regeneration applications.
Biography:
Miriela Tomás Oviedo has completed her Bachelor's degree at the age of 23 in the Faculty of Chemistry at the University of Havana. She has been working in the research department at Company Laboratories AICA. She is currently doing a research stay to complete her Master's degree at the Radiology Department of Leiden University Medical Centre (LUMC) in The Netherlands. She has presented 8 communications in International Scientific Congresses.
Abstract:
Contemporary bone repairing and regeneration techniques require biomaterials able to bond tightly to new bone, to permit bone growth and propagation. In this context, special attention has been given to chitosan / apatite composites (CHI/Ap) for bone regeneration because they have favorable properties of both components: bioactivity and osteoconductivity provided by apatite and degradation and flexibility supplied by chitosan. In this research CHI/Ap composites with different weight ratios (20/80; 50/50; 80/20) were obtained using a methodology for obtaining the inorganic apatite material in situ inside the chitosan matrix. The composites were characterized by Fourier transform infrared spectroscopy (FTIR) indicating the presence of the main functional groups of each component in the material. In vitro physiological stability and enzymatic degradation resulting materials were evaluated using solutions of phosphate buffered saline (PBS, pH =7.4). Composites with higher polymeric content showed the lowest physiological stability and the highest enzimatic degradation. The material bioactivity was demonstrated by deposition of a calcium phosphate layer with apatite morphology on the composites surface after immersion in simulated body fluid (SBF, pH=7.4). Preliminary cytotoxicity tests evidenced that the studied materials did not modify the natural proliferation of the hamster ovary cells (CHO-K1), demonstrating their cytocompatibility under physiological conditions. The results suggest that chitosan/apatite composites obtained are promising materials for bone regeneration applications.
Jeong Ok Lim
Kyungpook National University, South Korea.
Title: Fabrication of 3D printed dressing composed of VEGF peptide and hydrogel complex and evaluation for its wound healing capacity in vitro and in vivo
Biography:
Lim received her B.S in Korea, M.S. in Polymers at Cornell University, Ph.D. in Polymer Science at University of Massachusetts Lowell in 1993, and did postdoctoral fellowship at MIT, and Harvard Medical School. She was an Assistant Professor at the Wake Forest Institute for Regenerative Medicine (WFIRM) from 2004 through 2006. Currently she is Professor at Kyungpook National University School of Medicine in Korea and director of Joint Institute fior Regenerative Medicine (http://jirm.org). Dr. Lim served as President of Korea Tissue Engineering and Regenerative Medicine Society (KTERMS) and Program Chair of TERMIS-AP 2014 held in Daegu, Korea.
Abstract:
Printing technology offers a possibility of printing structurally complicated tissue scaffolds. Currently hardware and software of bioprinters are commercially available and printing three dimensional tissue contracts becomes possible. However, hurdles we face when we print biological structure are lacking of bioinks of good quality. Therefore, it is demanding to develop bioinks to successfully print biological matrix. Hence our research objective is to develop and optimize a bioink. We formualted a new bioink and investigated its rheological, chemical and biological properties for applicability to print skin patch for wound healing. This bioink is composed of VEGF peptide with 15 amino acids and hydrogel complex.. The peptide sequence, hydrogel-peptide ratio, stability and release kinetics were investigated for optimal cell viability, angiogenesis, skin regeneration and ultimately wound healing. Formulation was characterized in vitro for its 3D printability, resolution, temperature condition, mechanical stability, cell biocompatibility and degradability. And skin patch or dressing was examined for its safety and efficacy of wound healing in vivo using rat and pig model. The results from experiments demonstrated that newly formulated bioink is easy to print, gelling, not toxic, stable, and low cost. Therefore, VEGF peptide-gel complex has a great potential as a bioinlk for printing three-diemnsional structure for tissue reconstruction.
Biography:
Parisa Amouzgar was a post graduate pursuing her PhD at Monash University, Malaysia. She has wide interested in biomaterials .She did her research on application of chemically modified chitosan nano activated carbon beads with 3-aminopropyl triethoxysilane (APTES) and hexadecylamine (HDA) surfactants for Acetaminophen removal from aqueous solution.
Abstract:
The effects of modification conditions, such as surfactants concentration for APTES and HDA, and reaction time in APTES preparation were investigated in the adsorption process of ACT. Modified beads with these surfactants were compared with un-modified beads through characterization tests and in removal percentage of ACT. The chosen beading parameters were Cs concentration of 1.75 % (w/v) employing 70 % (w/w) of NAC, the dripping flowrate of 2 mL/min at a dripping distance of greater than 9 cm were used to form chitosan nano activated carbon (Cs-NAC) beads. APTES and HDA at varying amounts of 1 % - 3% (w/w) were impregnated in to the beads and parameters such as the concentration and reaction time (2-10 h) in adding APTES and HDA concentration were studied. It was found that APTES reduces the equilibrium time significantly from ~22- 24 h to 2-4 h as compared to unmodified beads. Nevertheless, addition of HDA inhibited the adsorption process due to formation of micelles. FESEM, XRD, FTIR, zeta potential, and Raman spectroscopy were used to characterize the developed beads and to confirm the adsorption of ACT on the surface of the beads in all the previous stages. Characterization tests also approved the surface modification of the beads with APTES. For the preparation method, 6 h of reaction time with APTES was sufficient for the beads with 40 % and 60 % NAC to reach the maximum uptake of ACT. On the contrary, modified beads with HDA had lower ACT uptake as compared to the unmodified Cs-NAC beads. The adsorption data were evaluated using Langmuir and Freundlich isotherms and the kinetics adsorption were analysed by pseudo-first order and pseudo-second order models. The isotherm data for the studied adsorbents could explain by Freundlich model and the kinetic results could fit properly within the pseudo-second-order rate model.
Bonwook Koo
Korea Institute of Industrial Technology ,Korea
Title: Derivatization of commercial vitamin A to develop the bio-based anti-aging cosmetic materials
Biography:
Bonwook Koo has completed his PhD at the age of 34 years from Seoul National University and postdoctoral studies from Norch Carolina State University (Dept. of Forest Biomaterials). He is a senior researcher of the KITECH, a government funded research institute of Korea. He has published more than 24 papers in reputed journals and has served as an editorial board member of BioMed Research International.
Abstract:
A vitamin A such as retinol is a well-known source material for anti-aging cosmetics due to its superior effects on the anti-wrinkle and anti-skin aging, and lots of cosmetic manufacturers have used it for the high-priced anti-aging products. However it mostly synthesized by chemical process and it should be a demerit as a cosmetic material. Thus a bioprocess should be developed to strengthen the competitiveness of the vitamin A based anti-aging products. The vitamin A is also easily oxidized in the air and the oxidation causes the side effects like the skin irritation and a poor delivery of the active ingredients into the skin. The stability improvement of the bio-vitamin A must be required to minimize its side effects and enhance the absorbability and moisturizing property of the final products.In this study, the derivatization of the retinol was performed to enhance the stability and the low-priced commercial retinol was used as a substitute material for the bio-based retinol with impurities. A commercial Retinol 50C (BASF) was separated from the additives and others by the column chromatography for the purification and the retinol purified would be applied to the derivatization. The retinyl acetate would be synthesized through the esterification with the acetyl chloride and the derivatives were finally recovered as the crystal through the crystallizing purification. Their structural and physicochemical properties were analyzed by 1H-NMR and FT-IR and it was confirmed that the purification of the low-priced retinol and the derivatization of the retinol purified were performed successfully.
Hassan Chaddad
University of Strasbourg, France
Title: Combining 2D angiogenesis and 3D Osteosarcoma microtissues to improve vascularization
Biography:
Hassan Chaddad has completed his Pharmacy degree from Lebanese Internationl University (LIU) and his Masters in Pharmacology from USEK University in Lebanon and now he is doing his doctoral studies (PhD) from Strasbourg University, Faculty of Medicine (France).
Abstract:
Introduction: The number of patients suffering from cancers worldwide is increasing, and one of the most challenging issues in oncology continues to be the problem of developing active drugs economically and in a timely manner. Considering the high cost and time-consuming nature of the clinical development of oncology drugs, better pre-clinical platforms for drug screening are urgently required. So, there is need for high-throughput drug screening platforms to mimic the in vivo microenvironment. Angiogenesis is now well known for being involved in tumor progression, aggressiveness, emergence of metastases, and also resistance to cancer therapies
Materials & Methods: In this study, to better mimic tumor angiogenesis encountered in vivo, we used 3D culture of osteosarcoma cells (MG-63) that we deposited on 2D endothelial cells (HUVEC) grown in monolayer. Combination 2D HUVEC/3D MG-63 was characterised by Indirect immunofluorescence, Scanning electron microscopy, Optical microscopy and mRNA expression (qPCR). Results: We reported that endothelial cells combined with tumor cells were able to form a well-organized network, and those tubule-like structures corresponding to new vessels infiltrate tumor spheroids. These vessels presented a lumen and expressed specific markers as CD31 and collagen IV. The combination of 2D endothelial cells and 3D microtissues of tumor cells also increased expression of angiogenic factors as VEGF, CXCR4 and ICAM1. Conclusion: The cell environment is the key point to develop tumor vascularization in vitro and to be closer to tumor encountered in vivo.
Aviroop Mukherjee
SRM Institute of Science and Technology, India.
Title: Graphene coated chitin plates based ballistic jacket guard using multistacking method
Biography:
Aviroop Mukherjee has completed his 12th Standard at the age of 18 years from Don Bosco School, Park Circus, Kolkata and is currently pursuing B.Tech from SRM Institute of Science and Technology in Biomedical Engineering. He is a former Biomechanical Research and Technical Analyst in a sports institution in Kolkata and is a current care-giver in PETA. He is also a member of the Indian Science Congress Association. He has published 7 research papers and is currently working on three major research projects.
Abstract:
Chitin is one of the most readily available forms of carbohydrate which is a complex form of glucose. This long chain polymer of N-acetylglucosamine is primarily found in the exoskeletons of arthropods, crustaceans and few other species. The chemical structure of chitin suggests that it can be compared to cellulose with its hydroxyl replaced with acetyl amine group. This allows the increased possibilities of hydrogen bonding between adjacent polymer molecules and this property forms the base on which the above mentioned development rests on.On close investigation of the most recent types of ballistic jackets in use, it was found that, in the anterior and posterior parts of the jacket that cover the trunk of the body, sheets of boron carbide have been employed in order to render the jackets such that they can block out the standard combat bullets upto 100 bullets with the impact trauma upto 13.5 mm.In comparison to the above, the above proposed development, Chitin, exclusively derived from Fish (Labeo rohita) scales and Lobster (Nephropsis) shells, was mixed with alpha-carbon graphene, in a base matrix of kevlar polymer. The inclusion of graphene improves the thermal resistivity of the chitin which contributes to the enhanced properties of the final product.Thereafter, sheets in the order of micrometers are drawn with this mixture and multiple such sheets are stacked together in order to obtain an optimum thickness. Finally, these multi-stacked sheets are then ready to be included in to the ballistic jackets.The novelty of this development is that, due to the unique integration of chitin with other specialised components, the physical and mechanical characteristics of it is such that it can effortlessly block out standard combat bullets of a much greater amount and from as close as 8-9 m firing distance, hence proving it to be better in properties than the present ones in use.
JIANG Yuanzhang
The Hong Kong Polytechnic University, Hong Kong China
Title: Synthesis and shape memory study of amino acid-based polyurethane
Biography:
JIANG Yuanzhang now is a master student in ITC, The Hong Kong Polytechnic University. He is doing research about amino acid-based polymer materials. He has published 2 papers in international journals and 2 Chinese Patents.
Abstract:
Polyurethane is widely used due to its high strength, high elasticity, wear resistance, and oil resistance. Polyurethane synthetic leathers, polyurethane foams, polyurethane coatings, polyurethane adhesives, urethane rubbers (elastomers) and polyurethane fibers are very common products. However, with the depletion of petroleum resources, the development of new bio-based polyurethanes is imperative. We successfully synthesized a new type of amino acid-based polyurethane. First, amino acid-based polyester diols are prepared by chemical synthesis, followed by prepolymerization with lysine diisocyanate, and finally lysine ethyl ester is added for chain extension to obtain amino acid-based polyurethanes. We also studied the shape memory behavior of the resulting material. This study not only provides new design ideas for biomaterials, expands its development direction, but also helps to improve the establishment of shape memory theory systems and lays a solid theoretical foundation for the further development of bio-based shape memory polymer materials.
H Torabzadeh Kashi
University of Tehran, Iran.
Title: Fabrication of Mg-4Y-2Nd-0.4Zr-0.25La microtubes for using as biodegradable stent in biomedical science
Biography:
Hessam Torabzadeh is a PhD student in the field of Mechanical Engineering at the University of Tehran. Hessam holds a BA in Manufacturing Engineering from Iran University of Science & Technology (2008-2012) and MA in Manufacturing Engineering from University of Tehran (2013-2015). He achieved the Iran National Elite Foundation award as a superior technician graduated in 2016. His research is primarily concerned with the production and characterization of nanostructured materials for different industries especially biomedical applications. He has published several papers and conference presentations and a book sponsored by Elsevier publication around Severe Plastic Deformation (SPD) methods for production of nanostructured materials.
Abstract:
Coronary heart disease (CHD) is the main cause of many deaths in our current world in which the coronary arteries are partially blocked or narrowed by the formation of plague. To solve this disease, angioplasty with stent placements has attracted a great deal of attention based on its lower levels of risk and acceptable efficacy. The traditional stents are made of 316L stainless steel and cobalt–chromium alloy which will indefinitely remain in the patients’ body and result in serious side effects like inflammation and thrombosis. In recent years temporary stents made from biodegradable metals especially Mg and its alloys have been considered as an alternative solution instead of the permanent ones, however, they face some profound limitations in their production process. In the current study, a new fabrication method including severe plastic deformation (SPD) process, direct extrusion, drilling, and microtube extrusion is proposed to produce Mg microtubes with improved mechanical properties. Based on previous studies, stents which are made from a material with an ultimate strength of >300 MPa and elongation of >15% can be a promising candidate for being used as biodegradable stents. By using the current method, large plastic strains are successively applied to the as-cast Mg at 400 ºC and consequently, the homogenous microstructure of the final microtube contains fine and ultrafine grains which causes high strength and high ductility Mg microtubes can overcome low formability of Mg alloys and facilitate the using of this promising material as biodegradable stents.