Biocompatibility of mussel-inspired water-soluble tissue adhesives.

Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion-based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet-adhesion strength, and long-term bonding.

Positive Charge Influences on the Surface Interactions and Cohesive Bonding of a Catechol-Containing Polymer.

Achieving robust underwater adhesion remains challenging. Through generations of evolution, marine mussels have developed an adhesive system that allows them to anchor onto wet surfaces. Scientists have taken varied approaches to developing mussel-inspired adhesives.

Sea squirt-inspired bio-derived tissue sealants.

Sea squirts' or tunicates' bodies are composed of cellulose nanofibers and gallol- functionalized proteins. These sea creatures are known to heal their injuries under seawater by forming crosslinks between gallols and functional groups from other proteins in their bodies. Inspired by their wound healing mechanism, herein, we have developed a tissue sealant using zein (a plant-based protein) and tannic acid (gallol-containing polyphenol).

Sustainably sourced components to generate high-strength adhesives.

Nearly all adhesives are derived from petroleum, create permanent bonds, frustrate materials separation for recycling and prevent degradation in landfills. When trying to shift from petroleum feedstocks to a sustainable materials ecosystem, available options suffer from low performance, high cost or lack of availability at the required scales. Here we present a sustainably sourced adhesive system, made from epoxidized soy oil, malic acid and tannic acid, with performance comparable to that of current industrial products.

Treatment of Staphylococcus aureus infection with sphingosine in ex vivo perfused and ventilated lungs.

Background: Ex vivo lung perfusion (EVLP) has expanded the donor pool for lung transplantation. Pulmonary Staphylococcus aureus infection, especially that caused by multidrug-resistant strains, is a severe threat to posttransplantation outcomes. Sphingosine is a lipid compound that exhibits broad-spectrum antibacterial activity.

Running the numbers on plant synthetic biology solutions to global problems.

Synthetic biology and metabolic engineering promise to deliver sustainable solutions to global problems such as phasing out fossil fuels and replacing industrial nitrogen fixation. While this promise is real, scale matters, and so do knock-on effects of implementing solutions. Both scale and knock-on effects can be estimated by 'Fermi calculations' (aka 'back-of-envelope calculations') that use uncontroversial input data plus simple arithmetic to reach rough but reliable conclusions.

Underwater Bonding with a Biobased Adhesive from Tannic Acid and Zein Protein.

Herein are presented several adhesive formulations made from zein protein and tannic acid that can bind to a wide range of surfaces underwater. Higher performance comes from more tannic acid than zein, whereas dry bonding required the opposite case of more zein than tannic acid. Each adhesive works best in the environment that it was designed and optimized for.

Effect of Cross-Linkers on Mussel- and Elastin-Inspired Adhesives on Physiological Substrates.

Surgical adhesives can be useful in wound closure because they reduce the risk of infection and pain associated with sutures and staples. However, there are no commercially available surgical adhesives for soft tissue wound closure. To be effective, soft tissue adhesives must be soft and flexible, strongly cohesive and adhesive, biocompatible, and effective in a moist environment.

Rare metal, precious adhesion.

Mussels use microfluidic assembly and vanadium to create an adhesive that anchors them in their natural environment.

Cytocompatibility of a mussel-inspired poly(lactic acid)-based adhesive.

Incorporating catechols into polymers can provide strong adhesion even in moist environments, and these polymers show promise for use in several biomedical applications. Surgical adhesives must have strong bonds, be biocompatible, and function in a moist environment. Poly(lactic acid) (PLA) has a long history as a biocompatible material for hard tissue device fixation.

Surface hydration for antifouling and bio-adhesion.

Antifouling properties of materials play crucial roles in many important applications such as biomedical implants, marine antifouling coatings, biosensing, and membranes for separation. Poly(ethylene glycol) (or PEG) containing polymers and zwitterionic polymers have been shown to be excellent antifouling materials. It is believed that their outstanding antifouling activity comes from their strong surface hydration.

Changing polymer catechol content to generate adhesives for high versus low energy surfaces.

Adhesive bonding is commonly used to replace mechanical fasteners in many applications. However, the surface chemistry of different substrates varies, making adhesion to a variety of materials difficult. Many biological adhesives are adept at sticking to multiple surfaces with a range of surface chemistries.

Genetic Diversity, Nitrogen Fixation, and Water Use Efficiency in a Panel of Honduran Common Bean ( L.) Landraces and Modern Genotypes.

Common bean ( L.) provides critical nutrition and a livelihood for millions of smallholder farmers worldwide. Beans engage in symbiotic nitrogen fixation (SNF) with Rhizobia.

Availability of Environmental Iron Influences the Performance of Biological Adhesives Produced by Blue Mussels.

Animals incorporate metals within the materials they manufacture, such as protective armor and teeth. Iron is an element used for adding strength and self-healing properties to load-bearing materials. Incorporation of iron is found beyond hard, brittle materials, even within the soft adhesive produced by marine mussels.

Weak Bonds in a Biomimetic Adhesive Enhance Toughness and Performance.

Developing future high performance adhesives is predicated upon achieving properties including strength and ductility. However, designing tough materials that are simultaneously strong and soft is usually contradictory in nature. Biological materials including shells and wood achieve impressive toughness by using weak bonds to connect larger structures at several length scales.

Agronomic Performance and Nitrogen Fixation of Heirloom and Conventional Dry Bean Varieties Under Low-Nitrogen Field Conditions.

Common beans () form a relationship with nitrogen-fixing rhizobia and through a process termed symbiotic nitrogen fixation (SNF) which provides them with a source of nitrogen. However, beans are considered poor nitrogen fixers, and modern production practices involve routine use of N fertilizer, which leads to the down-regulation of SNF. High-yielding, conventionally bred bean varieties are developed using conventional production practices and selection criteria, typically not including SNF efficiency, and may have lost this trait over decades of modern breeding.

Silk-Like Protein with Persistent Radicals Identified in Oyster Adhesive by Solid-State NMR.

The cement produced by the Eastern oyster, , may provide blueprints for waterproof biocompatible adhesives synthesized under benign conditions. The composition of this organic-inorganic composite, and of an organic extract, was characterized by C and H solid-state NMR and also compared with . shell and its organic extract.

Cooking Chemistry Transforms Proteins into High-Strength Adhesives.

In prior generations, proteins were taken from horses and other animals to make glues. Petroleum-derived polymers including epoxies and cyanoacrylates have since replaced proteins owing to improved performance. These modern materials come at a cost of toxicity as well as being derived from limited resources.

Critical factors for the bulk adhesion of engineered elastomeric proteins.

Many protein-based materials, such as soy and mussel adhesive proteins, have been the subject of scientific and commercial interest. Recently, a variety of protein adhesives have been isolated from diverse sources such as insects, frogs and squid ring teeth. Many of these adhesives have similar amino acid compositions to elastomeric proteins such as elastin.

Changes in Cementation of Reef Building Oysters Transitioning from Larvae to Adults.

Oysters construct extensive reef communities, providing food, protection from storms, and healthy coastlines. We still do not have a clear picture of how these animals attach to surfaces. Efforts described herein provide the first examination of adhesion at the transition from free swimming larvae to initial substrate attachment, through metamorphosis, and on to adulthood.

Examining Potential Active Tempering of Adhesive Curing by Marine Mussels.

Mussels generate adhesives for staying in place when faced with waves and turbulence of the intertidal zone. Their byssal attachment assembly consists of adhesive plaques connected to the animal by threads. We have noticed that, every now and then, the animals tug on their plaque and threads.

A bioinspired elastin-based protein for a cytocompatible underwater adhesive.

The development of adhesives that can be applied and create strong bonds underwater is a significant challenge for materials engineering. When the adhesive is intended for biomedical applications, further criteria, such as biocompatibility, must be met. Current biomedical adhesive technologies do not meet these needs.