Biological materials: Structure and mechanical properties

Nature has developed materials, objects and processes that function from the macroscale to the nanoscale. These have gone through evolution over 3.8Gyr. The emerging field of biomimetics allows one...

https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2009.0011

Biomimetics: lessons from nature--an overview.

http://barthelat-lab.mcgill.ca/files/papers/JPMS2009.pdf

Merger of structure and material in nacre and bone - Perspectives on de novo biomimetic materials

The present overview is intended to point the readers’ attention to the important subject of calcium orthophosphates. These materials are of the special significance because they represent the inorganic part of major normal (bones, teeth and dear antlers) and pathological ( i.e. those appearing due to various diseases) calcified tissues of mammals. Due to a great chemical similarity with the biological calcified tissues, many calcium orthophosphates possess remarkable biocompatibility and bioactivity. Materials scientists use this property extensively to construct artificial bone grafts that are either entirely made of or only surface-coated with the biologically relevant calcium ortho-phosphates. For example, self-setting hydraulic cements made of calcium orthophosphates are helpful in bone repair, while titanium substitutes covered by a surface layer of calcium orthophosphates are used for hip joint endoprostheses and as tooth substitutes. Porous scaffolds made of calcium orthophosphates are very promising tools for tissue engineering applications. In addition, technical grade calcium orthophosphates are very popular mineral fertilizers. Thus ere calcium orthophosphates are of great significance for humankind and, in this paper, an overview on the current knowledge on this subject is provided.

https://www.mdpi.com/1996-1944/2/2/399/pdf

Calcium Orthophosphates in Nature, Biology and Medicine

Biological materials: Functional adaptations and bioinspired designs

Biological materials are complex composites that are hierarchically structured and multifunctional. Their mechanical properties are often outstanding, considering the weak constituents from which they are assembled. They are for the most part composed of brittle (often, mineral) and ductile (organic) components. These complex structures, which have risen from millions of years of evolution, are inspiring materials scientists in the design of novel materials. This paper discusses the overall design principles in biological structural composites and illustrates them for five examples; sea spicules, the abalone shell, the conch shell, the toucan and hornbill beaks, and the sheep crab exoskeleton.

Structural biological composites: An overview

Through hundreds of millions of years of evolution, organisms have developed a myriad of ingenious solutions to ensure and optimize survival and success. Biological materials that comprise organisms are synthesized at ambient temperature and pressure and mostly in aqueous environments. This process, mediated by proteins, limits the range of materials at the disposal of nature and therefore the design plays a pivotal role. This article focuses on sharp edges and serrations as important survival and predating mechanisms in a number of plants, insects, fishes, and mammals. Some plants have sharp edges covered with serrations. The proboscis of mosquitoes and stinger of bees are examples in insects. Serrations are a prominent feature in many fish teeth, and rodents have teeth that are sharpened continuously, ensuring their sharpness and efficacy. Some current bioinspired applications will also be reviewed.

/pdf/the-cutting-edge-sharp-biological-materials-hkid4zw6v7.pdf

The cutting edge: Sharp biological materials

—Recent trends in
the field of prosthetic technology are shifting towards all-digital approaches.
These digital technologies have the potential to augment the current models of
clinical healthcare and reach more amputees than currently possible.
Unfortunately, most of the equipment needed to design and build digitally
shaped prostheses is expensive or requires a high level of expertise. Objective:
This paper developed several methods to enable the digital fabrication of
prostheses using only low cost tools that do not require extensive specialized training.
Methods: The authors built a cell phone application in Android Studio
that enables automated collection of image data which can be rendered into
accurate 3D-models using photogrammetry on a remote server. They then developed
a new protocol to shape these residual limb models into functional prosthetic
sockets using the freely available software Autodesk Meshmixer. Results:
Finally, the authors ran a case study where they rectified a prosthetic socket for
an amputee and compared this model to a socket built by a clinician. Conclusion:
This case study showed that these new methods can successfully create accurate
and functional prosthetic sockets. Significance: By leveraging
ubiquitous low cost smartphone technology, the authors believe that amputees in
underserved areas, who currently face large barriers both in cost and physical
access to proper care, could soon be able to obtain affordable prosthetic limbs.

/pdf/smartphone-telemedicine-a-novel-workflow-for-creating-1l5qcdix8z.pdf

Smartphone Telemedicine: A Novel Workflow for Creating Prosthetic Sockets Using Semi-automated Photogrammetry

Additive manufacturing is one of the most promising emerging technologies for building prosthetic sockets. However, there is no reliable way to estimate the factor of safety and the lifetime of 3D printed prosthetic sockets. Here, we explore 360° 3D digital image correlation (DIC) and discover how this new tool can increase our understanding of prosthetic structural failures. We establish that this new technology can dramatically improve the prosthetic design cycle by identifying local strain concentrations and by highlighting limitations in current simulated models. Overall, 360° 3D DIC technology empowers prosthetic engineers to characterize the performance of new materials and create innovative designs that are both safe and affordable.

/pdf/seeing-the-big-picture-improving-the-prosthetic-design-cycle-83p6ms20j4.pdf

Albert Y. Lin

Papers

Structural biological composites: An overview

The cutting edge: Sharp biological materials

Smartphone Telemedicine: A Novel Workflow for Creating Prosthetic Sockets Using Semi-automated Photogrammetry

Seeing the Big Picture: Improving The Prosthetic Design Cycle Using 360° 3D Digital Image Correlation