Biomorphic Polymers Inspired by Naturally Occurring Compounds in Skin

Innovation: Industry

Tissium

2013

Image: Petr Kratochvil / Needpix / CC BY SA - Creative Commons Attribution + ShareAlike

Modify Material Characteristics

The materials found in living systems are variable, yet often made from the same basic building blocks. For example, all insect exoskeletons consist of a material called chitin. Because material resources are limited, each material within or used by a given living system must frequently serve multiple purposes. Therefore, living systems have strategies to modify materials’ softness, flexibility, and other characteristics. To ensure survival, the benefits of these modifications must outweigh the living system’s energy and material expenditure to generate them. For example, spiders store the liquid components of spider silk in a gland, converting them into silk thread when needed. Some threads have different characteristics, such as elasticity and UV reflectance, than others.

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Modify Size/Shape/Mass/Volume

Many living systems alter their physical properties, such as size, shape, mass, or volume. These modifications occur in response to the living system’s needs and/or changing environmental conditions. For example, they may do this to move more efficiently, escape predators, recover from damage, or for many other reasons. These modifications require appropriate response rates and levels. Modifying any of these properties requires materials to enable such changes, cues to make the changes, and mechanisms to control them. An example is the porcupine fish, which protects itself from predators by taking sips of water or air to inflate its body and to erect spines embedded in its skin.

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Physically Assemble Structure

Living systems use physical materials to create structures to serve as protection, insulation, and other purposes. These structures can be internal (within or attached to the system itself), such as cell membranes, shells, and fur. They can also be external (detached), such as nests, burrows, cocoons, or webs. Because physical materials are limited and the energy required to gather and create new structures is costly, living systems must use both conservatively. Therefore, they optimize the structures’ size, weight, and density. For example, weaver birds use two types of vegetation to create their nests: strong, a few stiff fibers and numerous thin fibers. Combined, they make a strong, yet flexible, nest. An example of an internal structure is a bird’s bone. The bone is comprised of a mineral matrix assembled to create strong cross-supports and a tubular outer surface filled with air to minimize weight.

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Chemically Assemble Organic Compounds

Part of the reason that synthesis reactions (chemical assembly) can occur under such mild conditions as ambient temperature and pressure in water is because most often, they occur in a stepwise, enzyme-mediated fashion, sipping or releasing small amounts of energy at each step. For example, the synthesis of glucose from carbon dioxide in the Calvin cycle is a 15-step process, each step regulated by a different enzyme.

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Chemically Assemble on Demand

The vast majority of biochemical assembly and break down processes––even by the most complex organisms––occur within cells. In fact, cells are able to perform hundreds, even thousands, of chemical transformations at the same time under life-friendly conditions (ambient temperature and pressure in an aqueous environment). For example, venomous snakes store precursor molecules to instantly synthesize a suite of toxins via enzyme-mediated cascades.

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Patents

WO2019206998A1
489.5 KB PDF

TISSIUM are proprietary polymers that enable tissue reconstruction and adhesion.

Benefits

Multi-use
Biocompatible

Applications

Medical adhesives
Tissue engineering
3D printed implants
Drug delivery

UN Sustainable Development Goals Addressed

Goal 3: Good Health & Wellbeing

The Challenge

Tissue reconstruction after surgery presents many challenges. The tissue must be fully restored to its natural function while keeping scarring to a minimum. Traditional medical adhesives, such as glues or staples, are often not biodegradable and can sometimes cause further damage to the tissue.

Innovation Details

TISSIUM™ is a group of proprietary s inspired by fibrous keratins found in skin. The polymers can conform to and integrate with surrounding tissue in order to enable tissue reconstruction. It works by activating a viscous pre-polymer with a visible blue light. The resulting bond is both adhesive and elastic, allowing the polymer to comply with the underlying tissue while remaining strongly adhered. The polymer building blocks enable customization to match the tissue-specific requirements of specific therapeutic areas. The polymers could be integrated with peripheral nerve, gastrointestinal and cardiovascular systems. The pre-polymer can also be used as a resin to build high-resolution 3D-printed devices, or pre-loaded with drugs to use as a delivery system at multiple locations within the body.

Rendering of TISSIUM™ polymers helping to close a surgical wound. The viscous pre-polymer is activated on-demand, within seconds, using a visible blue light. The resulting bond is both adhesive and elastic.

Biological Model

Skin needs to protect the body while still being able to exchange water and ions. Fibrous keratins help to strengthen skin while simultaneously providing a structural support for lipids, which control the flow of liquids, primarily water, across the skin.