Bio-Nano Interfaces and Engineering Applications: Session I
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; Hannes Schniepp, William & Mary; Terry Lowe, Colorado School of Mines; Po-Yu Chen, National Tsing Hua University

Monday 8:30 AM
March 20, 2023
Room: Sapphire 400A
Location: Hilton

Session Chair: Hannes Schmidt, William & Mary; Candan Tamerler, University of Kansas


8:30 AM  Invited
An Insight into Cellular Protein Mechanics during Cancer Progression: Dinesh Katti1; Sharad Jaswandkar1; Hanmant Gaikwad1; Kalpana Katti1; 1North Dakota State University
    The evolution of mechanobiology of cancer cells during cancer progression is associated with the dynamics of several cellular proteins. The cellular proteins actin and integrin play a critical role during cancer progression. The dynamic remodeling of an actin cytoskeleton is observed in cellular processes such as tumor cell transformation and metastasis. The adhesion protein integrin is essential in adhering cancer cells to the extracellular matrix and mechanotransduction. Here, we present the mechanics of these two crucial proteins using steered molecular dynamics simulations and their potential roles in the mechanobiology of breast and prostate cancers during progression at the bone metastasis site. Our simulations unravel the fundamental mechanisms that play a vital role in cancer cell cytoskeletal and adhesion dynamics during cancer progression at the bone metastasis site.

9:05 AM  
From Molecular Interactions to Macroscopic Properties: Studying Protein-based Structural Materials Across the Scales: Hannes Schniepp1; 1William & Mary
    Proteins are the building blocks for some materials with outstanding mechanical properties, such as spider silk, which rivals the strength of steel. Given that interactions between protein molecules are only based on “weak” secondary interactions, such as hydrogen bonds and van der Waals forces, this is quite surprising. To understand this phenomenon, we have studied spider silk across the length scale with a plethora of experimental and computational techniques, including vibrational spectroscopy, nuclear magnetic resonance techniques, X-ray diffraction, as well as AFM imaging and force spectroscopy. We have developed a sophisticated multi-scale model of the structure and interactions between the different components of this hierarchical material, which has allowed us to establish a trace between molecular-scale interactions and macroscopic mechanical properties. This approach provides a deep understanding of existing materials and an assessment of the potential of future designer materials based on proteins and peptides.

9:35 AM  
Antimicrobial Peptide-polymer Hybrids Towards Next Generation Dental Adhesives: Kalea Chu1; Kyle Boone1; Aya Cloyd1; Qiang Ye1; Paulette Spencer1; Candan Tamerler1; 1University of Kansas
    In 2020, an estimated 3.9 billion people suffered from dental caries, making caries the premiere chronic oral disease on Earth. The common treatment for this condition consists of removing infected tissue, followed by repairs with adhesive-bonded composite. However, fragile adhesive bonds are readily damaged by acids and oral fluids. Bacteria, namely S. mutans, infiltrate the resulting gaps at the composite-tooth interface, demineralizing the tooth, and further eroding the adhesive. Degradation of the composite margin where adhesive is applied engender secondary decay and restoration failure. To address this vulnerable site, we designed targeted antimicrobial peptides (AMPs) to be introduced at the adhesive-tooth interface, where failure originates. Via iterative machine learning, these AMPs are designed as peptide-polymer hybrids to display both antimicrobial activity and self-strengthening abilities as next generation adhesives. They demonstrate remarkable promise for aiding the fight against caries, as well as design potential for applications outside the oral microbiome.

9:55 AM Break

10:10 AM  Invited
Nanostructural Bone Remodeling at the Interface to Mg Implants: Helga Lichtenegger1; Thomas Bretschneider1; Annelie Weinberg2; Nicole Sommer2; Omer Suljevic2; Christian Hellmich3; Lukas Pircher3; Nicole Zechmann3; Tilman Gruenewald4; Irene Rodriguez5; Andreas Menzel5; 1University of Natural Resources and Life Sciences (BOKU); 2Medical University of Graz; 3Technical University of Vienna; 4Institut Fresnel, Marseille; 5Paul Scherrer Institute
     Bio-resorbable magenisum implants have moved into the focus of research in recent years. Since bone is a complex, highly adaptive material and known to react to mechanical stimuli and chemical influences, implant placement and successive degradation alters the bone structure. Here we study the changes of the nanostructure of rat bone in response to the presence and different degradation stages of Mg implants by Small Angle X-ray Scattering (SAXS), Small-Angle Scattering Tensor Tomography (SASTT) and electron microscopy. We correlate our results with local mechanicl properties and first results from mechanical modeling. We find that the local preferred orientation of the collagen-mineral composite is highly sensitve to changing load situation. Experiments involving physical training of rats show a pronounced influence on the bone healing. This type of knowledge is also expected to be highly relevant for clinical application and could be used to optimize patient recovery and mobility.

10:45 AM  
Influence of Nanoscale Hydration on the Micro-structural Properties of Human Cortical Bone: Elizabeth Montagnino1; Glynn Gallaway1; Thomas Siegmund1; John Howarter1; 1Purdue University
     Hydration at the nanostructural level of bone, a hierarchal composite material, has an essential role in fracture resistance. Bound water found within the collagen triple-helix increases the volume of the organic matrix while, water at the collagen-mineral interface transfers load between the phases, both having an influence of the overall fracture toughness. Small-angle x-ray and wide-angle x-ray scattering (SAXS/WAXS) was used to characterize D-spacing under tensile load for bone specimen with controlled degrees of internal hydration. To modulate the water in the organic matrix and at the collagen-mineral interface, human cortical bone samples were partially dehydrated and demineralized in controlled environments and then treated under pharmaceutical conditions to understand the ability of the organic matrix to hydrate and improve the mechanical response of the bone.This work is supported by NSF Award 1952993

11:05 AM  
Dental Application of Nano-Zirconia: Joy Iyamu1; Ikhazuagbe Ifijen2; Obehi Ogudu2; Aiyevbekpen C. Ehigie1; Osahon K. Ogbeide1; 1University of Benin, Benin City, Edo State, Nigeria; 2Rubber Research Institute of Nigeria
    A form of dental ceramic known as nano zirconia (Zr NPs) or Nano-ZrO2 has recently made great strides in the world of dental care thanks to its remarkable biocompatibility, optical, biological, superior mechanical, and stable structure. The availability of metal-free alternatives is one of the most crucial criteria for dental materials. Zirconia is frequently utilized for dental applications since many regularly used metal alloys have undesirable colors and chemical interactions in the mouth cavity. Zr or ZrO2 NPs-based ceramics have garnered a lot of interest in place of conventional biomaterials because of their higher corrosion resistance, better color matching that enhances aesthetics, and increased strength. As a result, this review offers a summary of recent studies on Zr NPs or Nano-ZrO2 applications in dentistry as well as the potential of the surfaces of dental implants in the future.

11:25 AM  
Multi-functional Peptide-mediated Intrafibrillar Remineralization for Dental Tissue Repair: Aya Cloyd1; Kye Boone1; Qiang Ye1; Paulette Spencer1; Candan Tamerler1; 1University of Kansas
    Dental caries are the most prevalent chronic disease globally, affecting nearly 3.9 billion people. One-third of the world’s population suffers from untreated caries and underserved populations are disproportionally affected. To date, resin composites used for dental tissue restoration show poor longevity and require subsequent clinical interventions due to critical failure in the dental adhesive. Poor adhesive infiltration of demineralized collagen leaves collagen fibers exposed and the adhesive-dentin hybrid layer open to bacterial degradation and further demineralization. Our approach investigates a multi-functional peptide-mediated intrafibrillar remineralization approach to strengthen this vulnerable site. We engineered a bifunctional peptide that binds to collagen and mediates enhanced localized remineralization. We will share our promising experimental results to repair this complex interface using combined spectroscopic and microscopic characterization including AFM, and SEM-EDX. Our studies provide a critical step toward developing a next generation peptide-enabled dental adhesive that effectively repairs caries-affected dentin.