Bio-Nano Interfaces and Engineering Applications: Bio-Nano II
Sponsored by: TMS Functional Materials Division, TMS Structural Materials Division, TMS: Biomaterials Committee
Program Organizers: Candan Tamerler, University of Kansas; Kalpana Katti, North Dakota State University; Hendrik Heinz, University of Colorado Boulder; Terry Lowe, Colorado School of Mines; Po-Yu Chen, National Tsing Hua University

Monday 2:00 PM
March 15, 2021
Room: RM 12
Location: TMS2021 Virtual

Session Chair: Candan Tamerler, University of Kansas; Feride Sermin Utku, Yeditepe University


2:00 PM  Invited
Flexible-glass Like Coating onto PTFE Vascular Graft Material via Nonthermal Plasma Process: Vineeth Vijayan1; Bernabe Tucker1; Yogesh Vohra1; Vinoy Thomas1; 1University of Alabama at Birmingham
    PTFE is a fluoropolymer that is widely used as a vascular graft substitute in cardiovascular and hemodialysis applications, but only for large- and medium-diameter PTFE vascular grafts. For small-diameter PTFE vascular grafts, there are considerable risks for thrombosis – blood clotting – and a lack of endothelial cell growth and associated intimal hyperplasia. Non-thermal plasma-polymerized hydrophilic glass-like coating provided a blood compatible material interface. Spectral and microscopic analyses were carried out for the coating characterization. The augmented PTFE surfaces demonstrate better endothelial cell adhesion and reduced platelet adhesion without changing the mechanical flexibility of the graft.According to the American Society of Nephrology more than 300,000 Americans have end-stage renal disease and are depending on artificial dialysis to stay alive. In the context of COVID-19, there are increased cases in the number of ICU dialysis patients due to severe kidney infections and blood clots.

2:30 PM  
Detection of Limonene Using Graphene Field Effect Transistor Modified by Self-assembling Peptide: Chishu Homma1; Yoshiaki Sugizaki2; Atsunobu Isobayashi2; Yuhei Hayamizu1; 1Tokyo Tech; 2Toshiba Corporation
    Graphene, a representative two-dimensional material, has excellent electronic properties due to its high mobility and specific surface area. Biosensors based on graphene field-effect transistor (GFET) are expected to be applied in various fields such as medical diagnosis, environmental monitoring, and security management. In this study, we developed a new technique to detect an odor molecule, which is relatively small and volatile. We utilized rationally designed peptides as a molecular scaffold and probe peptides on graphene surface. Then, we performed odor sensing with GFETs to detect limonene, a representative molecule for the smell of lemons. We successfully detected limonene with high sensitivity in an electrical manner. This work was supported by the Cabinet Office (CAO), Cross-ministerial Strategic Innovation Promotion Program (SIP), “An intelligent knowledge processing infrastructure, integrating physical and virtual domains” (funding agency: NEDO).

2:50 PM  
Enhancing Electrochemical Detection of Choline Using Molecularly Imprinted Polymer Electrode: Sermin Utku1; Sevgul Bakay2; Adil Denizli3; Inci Cilesiz4; 1Yeditepe University Biomedical Engineering; 2Duzce University; 3Hacettepe University; 4Istanbul Technical University
    Molecularly imprinted polymeric surfaces enable quantitative and/or qualitative analysis of analytes using the biological recognition sites created on the electrodes. A molecularly imprinted choline pencil graphite small-molecule biosensor with surfaces containing 0.2 M and 0.5 M choline were generated for the quantitative detection of choline using cyclic voltammetry, electrochemical impedance spectroscopy in a three-electrode electrochemical cell in pM-μM choline solutions. The amount of choline bound to the complementary recognition sites on the electrodes correlated with the change in current, voltage and impedance. TRIS (hydroxymethyl) aminomethane as a competitive small-molecule demonstrated specificity for choline. Blood serum choline concentration was determined as 10.64 ± 0.546 µM. The detection range for the 0.2M electrodes was determined as 71.6 pM-7.16 µM with a 71.6 pM limit. Based on these results, a lower limit of detection of small-molecules has been obtained than those obtained by electrochemical methods only.

3:20 PM  
Developing Nanostructured Metals for Innovative Medical Implants with Improved Design and Biofunctionality: Ruslan Valiev1; Evgeny Parfenov1; Olga Kulyasova1; 1UFA State Aviation Technical University
    Recent years have witnessed a series of numerous investigative activities to improve existing metallic biomaterials (Ti and Ti alloys, stainless steels, Mg and Fe alloys) by their nanostructuring for advanced medical applications using severe plastic deformation (SPD) processing. Nanostructured metals are peculiar for their enhanced strength and fatigue life, which makes them an excellent choice for fabrication of implants with improved design for dentistry and orthopedics. In this report, we also show that surface modification of nanometals by chemical etching and bioactive coatings leads to a significant improvement of biomedical properties. We demonstrate different examples of fabrication of miniaturized dental implants and nanoTi plates with enhanced osseointegration.

3:40 PM  Invited
The Mechanical Significance of Sublamellar Organization of Mineralized Collagen Fibrils: Sermin Utku1; 1Yeditepe University Biomedical Engineering
    Bone consists mainly of Type I Collagen, hydroxyapatite, mucopolysaccharides and bone fluid. The collagen and mineral plate orientations affect bone mechanics. The organic component of lamellar bone was modelled to contract towards the mineral by dehydration, forming a contraction vector as the surface normal of the mineral plate. The amount of dehydration based contraction in the rotated collagen fibrils was calculated for the sublamellar model, where the mineral plate of the 0° [001] sublamellar collagen fibril was oriented along the y (010) plane. Projections of sublamellar contraction vectors were denoted as u, v and w displacements at 10°-20°-30° angles and summed to give the lamellar total and the anisotropy ratios of properties in directions parallel (w) versus perpendicular (u or v) to the osteon. The large variation in calculated wet and dry bone anisotropy ratios demonstrates the significance of the effect of collagen and mineral plate orientation on bone mechanics.