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Composites or composite materials are engineered materials that consist of two or more constituent materials with wide discrepancies in their physical, chemical, and mechanical properties. The characteristic properties of these composite are as a result of the individual properties of their constituent parts and their respective volume fractions and arrangements in the material system. Depending on the intended application, composites can be designed to satisfy specific geometrical, structural, mechanical, chemical, and sometimes aesthetic requirements. Areas of application of these synthetic materials includes construction such as in buildings and bridges, automotive industry such as in car bodies, aeronautic, naval (e.g., ships and boats), and in the biomedical fields. Although metallic, polymeric and ceramic biomaterials have been in use for medical treatments such as tissue repairs and replacements for decades, composites are just coming to light. Therefore, the main purpose of this paper is to introduce composite materials and discuss their current and potential use in the biomedical field.

Medial patellofemoral ligament (MPFL) reconstruction usually involves hamstring autografts and is associated with donor-site morbidity. Excellent short-term results with MPFL reconstruction using synthetic materials have been reported. Although synthetics do not sacrifice autologous tissues, their material properties are significantly different from those of biological tissues. Therefore, accurate surgical procedures are required to achieve excellent results. The purpose of this report was to describe our surgical method for MPFL reconstruction using FiberTape and knotless SwiveLock anchors.

Materials in nature have fascinating properties that serve as a continuous source of inspiration for materials scientists. Accordingly, bio-mimetic and bio-inspired approaches have yielded remarkable structural and functional materials for a plethora of applications. Despite these advances, many properties of natural materials remain challenging or yet impossible to incorporate into synthetic materials. Natural materials are produced by living cells, which sense and process environmental cues and conditions by means of signaling and genetic programs, thereby controlling the biosynthesis, remodeling, functionalization, or degradation of the natural material. In this context, synthetic biology offers unique opportunities in materials sciences by providing direct access to the rational engineering of how a cell senses and processes environmental information and translates them into the properties and functions of materials. Here, we identify and review two main directions by which synthetic biology can be harnessed to provide new impulses for the biologization of the materials sciences: first, the engineering of cells to produce precursors for the subsequent synthesis of materials. This includes materials that are otherwise produced from petrochemical resources, but also materials where the bio-produced substances contribute unique properties and functions not existing in traditional materials. Second, engineered living materials that are formed or assembled by cells or in which cells contribute specific functions while remaining an integral part of the living composite material. We finally provide a perspective of future scientific directions of this promising area of research and discuss science policy that would be required to support research and development in this field., Materials Today Bio, 11, ISSN:2590-0064

Wound healing is a challenging complex process which is usually difficult to manage. Effective wound dressing approaches which could accelerate and facilitate the skin regeneration are gaining great importance worldwide. In this regard the bioactive polymers could be helpful for the healing process with their antimicrobial, immune-modulatory, cell proliferative, and angiogenic properties provide great opportunity to protect the brittle skin. These polymers with biodegradability, renewability, biocompatibility, and lower antigenicity properties are preferred over the synthetic materials. Many studies have been conducted during the past 10 years for fabricating biopolymer-based hydrogels, which led to define the ideal conditions for wound healing. This chapter mainly emphasizes on introducing desirable characteristics of the biopolymeric-based wound dressings.

Innovation of sustainable materials is guided by the usage of synthetic materials and nonrenewable sources. Biopolymers are engineered for an array of applications because of their multidimensional characteristics, including biodegradability, biocompatibility, and excellent mechanical as well as optical properties. Adhesive technology can be directed to employ renewable materials that exhibit equal or outstanding performance in contrast to other conventional counterparts. Satisfactory life span and lightweight automobile parts as a way to facilitate car fuel utilization, and in this manner cut the outflow of ozone-depleting substances, will continue to prompt extended research into the practicality of polymers and their composites for use in cars.

Due to rapid technological advancement, the continuous supply of raw materials is one of the biggest challenges today. Bio-derived raw materials which are environmentally friendly, nontoxic, and compatible with traditional synthetic materials can be an excellent alternative resource for the implementation of industrial-scale product developments. Sustainable and renewable biomaterials are being used as raw materials for composite fabrication and considered as potential candidates for various manufacturing industries. Automotive, biomedical/health care, wastewater purification, and packaging industries are implementing biocomposites for their production. Various types of biocomposites based on ceramics, polymers, and metals are discussed for their industrial applications with corresponding physical, chemical or mechanical properties.

Energy storage devices have a crucial role in handling energy consumption in various applications like automobiles and electronic devices. Materials used to fabricate these devices, like supercapacitors and batteries, are able to control the efficiency and lifetime of the devices. To achieve maximum efficiency and durability of the devices, the design and combination of different components of these devices are crucial. Although we are able to achieve good performance with synthetic materials, they have several drawbacks due to their synthetic background and environmental issues concerning synthetic methodology as well as processing. Production, utilization, and disposal are usually part and parcel of all kinds of technology and disposal of materials is of great concern because some are harmful to the environment. Biopolymer materials provide solutions to overcome issues produced by synthetic materials due to their availability in nature. In this chapter we discuss the utilization of biopolymer-based devices, which are also able to solve future environmental issues of these technologies.

The use of nanolarvicide has been proposed to control the neglected tropical diseases (NTDs), reducing the environmental impact of active ingredients, and improving the treatment effectiveness. The proposal of eco-friendly nanoproducts, including alternative processes using natural products, has been considered promising. In addition, the use of natural products as larvicide has shown interesting results, making them useful to produce nanoecolarvicides. This approach is a sustainable trend to control the main vectors. The nanolarvicide formulations include metallic particles, especially those produced by green synthesis, polymeric nanoparticles, and nanoemulsions, responsible for improving the effectiveness of larvicides in aquatic environments.

With developments in technology, it has now become possible to reduce natural or synthetic materials to nanodimensions. Materials that are brought to the nanosize with the methods named as top or bottom in this chapter exhibit unique physical, chemical, and mechanical properties and high performance. Due to these properties, nanomaterials (NMs) are used with increasing frequency in sensor technologies, diagnosis and treatment technologies in medicine, industry, biological processes, chemical processes, and many other technological fields. This chapter offers the opportunity to recognize NMs from a broad perspective by making the definition of NMs and their classification according to their size, shape, and composition. © 2021 Elsevier Inc. All rights reserved.

Breast tissue engineering may provide a biologically based method for reconstruction following breast cancer surgery (mastectomy or lumpectomy) or for cosmetic augmentation of breast tissue. Breast tissue engineering also may provide a method to develop a personalized benchtop tissue test system that can be used to study key aspects of normal processes, a disease, to assess integrated tissue and organ systems, to screen drugs or vaccines or test therapies. This chapter focuses on breast cancer–related tissue engineering. Regardless of the endpoint, in vitro or in vivo, certain common approaches and challenges exist in engineering breast tissue. The ability to construct three-dimensional (3D) tissue requires the appropriate selection of cells and biomaterials and the ability to perfuse the tissue. Although early tissue-engineering approaches focused largely on implantation of differentiated cells, equal emphasis has been placed on stem or stem-like cells. A wide variety of biomaterial chemistries have been assessed, including naturally derived and synthetic materials, as have a wide variety of formulations and presentations, including injectable and noninjectable ones. Breast tissue engineering for in vivo application has more design constraints than breast tissue engineering for benchtop use; indeed, 3D benchtop tissue systems can be built to replicate aspects of a complex disease state, including integration of multiple engineered tissues or organs. In addition, benchtop systems may be used to evaluate and improve tissue-engineering systems for reconstruction, or other medical implants. A large focus is on developing high-throughput, high-resolution means of building key aspects of these complex benchtop tissue systems. It is now widely recognized that 3D test systems may provide a missing bridge to the better design and understanding of implantable systems and disease states.

Silk is a natural macromolecular protein polymer being widely explored in various biomedical applications. Their excellent biocompatibility, controllable degradation rates, and remarkable mechanical properties help to re-engineer proteins into different material formats to serve diverse end-use specific applications. Since the last few decades, silk proteins are being extensively exploited for biomedical applications against current synthetic materials that lack bio-compatibility and bio-degradability. Further scientific exploration of silk proteins promises the continuous advancement of sericulture industries in India. Therefore, this chapter is structured to review the prospective applications of silk proteins in diversified areas, their properties, and application as natural biomaterials.

Bionanocomposites are a novel class of advanced biohybrid materials. Today, industrialists and researchers are looking toward bionanocomposites to solve environmental problems and to find alternative sources for petroleum-based chemicals. They have developed bionanocomposite materials with excellent biocompatibility and biodegradability, by using excellent green technology. However, biopolymers present relatively poor mechanical and barrier properties, which currently limit their industrial use. There is a growing interest in developing bio-based polymers and innovative process technologies that can reduce the dependence on fossil fuel and move to a sustainable raw materials base. Bionanocomposites open an opportunity for the use of new, high-performance, lightweight, green nanocomposite materials to replace conventional nonbiodegradable petroleum-based plastic packaging materials. This chapter provides a broad overview of the literature of synthetic materials to bionanocomposites, their properties, their processing, and their applications.

Although bone grafting with autologous or allogeneic sources still remains as a gold standard, there is high demand for alternative approach for the treatment of patients. Various biomaterials including natural or synthetic materials, and their composite have been utilized for rapid bone regeneration. However, conventional biomaterials are not ideal and those enabling simultaneously provision of structural support and active induction of tissue regeneration are needed. In particular, frontiers in bone biomaterials have been designed with capability of delivering biologic, structural, and compositional features of natural bone extracellular matrix microenvironment. In this review, we categorize and summarize representative approaches.

One of the biggest challenges in modern chemistry is the preparation of synthetic materials with life-like behavior for the assembly of artificial cells. In recent years, numerous artificial systems that mimic cellular components and functions have been developed. Supramolecular chemistry plays a key role in such cell mimics given that non-covalent interactions control the shape and function of many biomolecules, such as DNA base pairing, protein structure, ligand-receptor binding, and lipid membrane packing. However, the complexity of living cells constitutes a major challenge for their bottom-up assembly from pure synthetic materials. Inspired by the building blocks of nature, a wide range of supramolecular systems have been developed to reproduce cellular functions such as cell-cell communication, signaling cascades, and dynamic cytoskeleton assemblies. This review surveys a selection of key advances in synthetic derivatives of biomolecules with supramolecular organization and life-like behavior by addressing their non-covalent foundation and integration as increasingly complex protocell models This work was partially supported by the Spanish Agencia Estatal de Investigación (AEI; SAF2017-89890-R), Xunta de Galicia (ED431C 2017/25, 2016-AD031, and ED431G/09), ISCIII (RD16/0008/003), and the European Commission (EC; European Regional Development Fund). I.I. thanks the EC and AEI for MSCA-IF (2018-843332) and JdC (FJCI-2017-31795) fellowships, respectively. J.M. received a Ramón y Cajal grant (RYC-2013-13784), an ERC-Stg grant (DYNAP-677786), and a Young Investigator Grant from the Human Frontier Science Program (RGY0066/2017) SI

Artificial photosynthesis is a promising strategy for carbon dioxide (CO2) reduction to produce hydrocarbon fuels as well as other value added products. CO2 reduction has been supreme resolution in order to mitigate the global warming and climate change and to explore the possibilities to produce renewable energies. However, the development of high-efficient artificial/synthetic photoactive materials toward CO2 reduction is very challenging as these synthetic materials often exhibit low thermodynamic stability and high rate of recombination of charge carriers during the photocatalytic process. Consequently, there are a variety of approaches such as the physical and chemical modifications of materials that have been explored toward mimicking the photosynthesis process efficiently. Of such various approaches, the development of hierarchical nanostructuring of photocatalytic materials is promising and versatile toward achieving high quantum efficiencies in CO2 conversion into fuels.

Living tissues can be healed after being damaged. If synthetic materials based on natural polymers also show self-healing properties, their life span can be maximized, with the consumption of limited natural resources being reduced. This need can be fulfilled by recent advances in chemical technologies, which make the generation of self-healing hydrogels possible. In this chapter, methods of generating self-healing hydrogels, especially those derived from natural products, are introduced. Current strategies for designing hydrogel microstructures for self-healing purposes and for characterizing the performance of a self-healing hydrogel generated from natural polymers are also reviewed. The aim of this chapter is to inspire the development of self-healing hydrogels for biomedical applications.

Gillnets are among the most widely used fishing gear in global fisheries because of their simplicity, high operability, catch efficiency and low entrance cost for fishermen. In Norway, the Northeast Atlantic (NEA) cod (Gadus morhua) fishing industry represents the most important economic single species fishery and the gillnet fishery accounts for 24% of the national total allowable catch (TAC) of NEA cod. Despite the importance of the gillnet fishery in Norway, significant amounts of gillnets are lost at sea each year. As gillnets are made of synthetic materials (i.e. nylon) with high breaking strength and durability, lost, abandoned and/or discarded fishing gear (LADFG) continues catching target and non-target species for years. This phenomenon, known as "ghost fishing", cause negative impact on the benthic marine environment and to the fisheries management. Over the last years, the development of biodegradable gillnets to replace traditional nylon gillnets has become particularly sought after in fisheries worldwide. However, biodegradable gillnets are less efficient and more expensive than traditional nylon gillnets. As the urgency to eliminate the negative environmental impacts of LADFG increases, a crucial question remains how to successfully implement biodegradable gillnets to replace the more efficient nylon gillnets currently used in commercial fisheries. In this article we investigate how central elements of fisheries management may be used to implement biodegradable gillnets and how this may challenge the current resource allocation policy among different gear- and vessel groups.

The study of electromagnetic (EM) interactions with materials has a rich and long history dating back to Maxwell, Lord Rayleigh, Fresnel, and many others. Over these nearly 200 years, EM material development and applications have blossomed dramatically, culminating in the recent developments of metamaterials and metasurfaces. The prefix “meta” is a Greek preposition meaning (along with other things) “beyond”. Metamaterials are novel synthetic materials engineered to achieve unique properties not normally found in nature, i.e., materials beyond those occurring naturally. Metamaterials and metasurfaces are often engineered by arranging a set of small scatterers in a regular array throughout a region of space, thus obtaining some desirable bulk behavior or desired surface behavior. In this chapter we will discuss different aspects of these various metastructures, including a historical perspective, a discussion on the characterization of these metastructures, and a discussion on how these different metastructures behave on different length scales (that is, periodicity and inclusion size relative to the wavelength of interest).

As the understanding of the mechanical causes of conditions has led to development of the vast array of mechanical treatments, so has the knowledge of the biologic etiology driven the rise of orthobiologic treatments. These options include autogenous or allogeneic tissues, cells, or growth factors, biologically derived materials, and synthetic materials. The autogenous materials are platelet-rich plasma (PRP), bone marrow concentrate (BMC), and autologous fat tissue–derived preparations, including stromal vascular fraction (SVF) and “fractured fat.” Allogeneic products include placental and amniotic membranes/fluids that contain numerous growth factors. Recombinant growth factors (e.g., recombinant human bone morphogenetic protein—rhBMP and recombinant human platelet-derived growth factor—rhPDGF) and synthetic compounds (hyaluronic acid, calcium phosphate, or calcium sulfate) are also used to treat conditions. The nature of these treatments and their applications continue to expand our ability to help heal our active patients.

Summary Blood vessels convey essential nutrients to end organs, and when diseased, they must be replaced or bypassed. Traditionally plastic and synthetic materials have been used but are susceptible to thrombosis, stenosis, and poor patency rates. A recent report in Science Translational Medicine describes a decellularized matrix grown in vitro from commercially sourced fibroblasts that can be used as a vascular graft. Fibroblasts are grown for several weeks on a fibrin scaffold, laying down a collagen layer. After decellularization and transplantation as an arteriovenous fistula, this group showed that grafts remained patent for several weeks. The lack of cellular material in this graft at the time of transplantation reduced the risk of immune rejection. The matrix laid down by the fibroblasts can serve as a scaffold for recipient cells to colonize after implantation, but also provides structural support for arterial blood flow. Other tissue-engineered grafts of decellularized matrices have recently been tested in clinical trial. For these strategies, the cell type, scaffold material, and culture conditions are key components that dictate not only the type and quality of the end product, but also allow standardization and quality control necessary for widespread translation into clinical use. These off-the-shelf decellularized products may be the first in a new generation of therapies for patients with cardiovascular disease., Central Illustration

Esthetic features of life are of great general importance to people. Teeth are of significance in this regard as they somehow are the key elements of individuals’ character by reflecting the amount of attention one may receive among the public by means of communication. In this sense a subfield of medicine, called dentistry, has been specialized for identifying the diagnosis, prevention, and treatment of the diseases, disorders, and the conditions of oral cavity, as well as related structures and tissues. Meanwhile, there has been a significant progress in the past decades associated with the design and manufacture of dental materials. Correspondingly, so many compounds and formulations have been produced to gain advanced materials for dental applications. Dental impression materials (IMs) have been utilized as negative molds to fabricate appropriate casts, by which different trays have been utilized as supports for the IMs to fit over the dental arches. Although various natural and synthetic materials have been utilized so far as dental IMs, they are frequently classified based on their properties into two groups, that is, elastic and inelastic families. In addition to the stiffness, other features, such as stability, accuracy, and wettability, play essential roles in IM performance. In this overview, materials utilized for their impression function are dealt with, and their properties are discussed to pave a way for those seeking appropriate materials for dental prosthesis purposes.

As mentioned in Section 6.1 , all real materials have internal microstructure at various length scales, and some examples were shown in Figs. 6.1–6.3 1 2 3 . Recently, there has been considerable demand on structural performance and this has led to the development of many new heterogeneous synthetic materials with complex microstructures that help provide the desired material properties. Our previous continuum mechanics theories have generally been developed for problems with length scales several orders of magnitude larger than these microstructural features. In this fashion, microstructure is then averaged over these heterogeneous material phases to allow standard continuum mechanics to be employed. We now wish to explore theories that attempt to model some of these microstructural effects by embedding additional features into the classical field equations. Over the last few decades, numerous theories have been developed. Since this is a textbook, we will limit our study and primarily explore several micromechanical continuum theories coupled with linear elasticity. In this fashion, we can easily develop the basic formulations and find a few closed-form micromechanical solutions to compare with corresponding classical predictions. This will provide the reader with some basic micromechanical background on formulation concepts and solution results. Within the elasticity context, we will discuss micropolar, distributed voids, doublet mechanics, higher-gradient theories, fabric tensor models, and some fundamental aspects of damage mechanics.

Millions of people suffer from dental caries, which affects the quality of life of patients of all ages. Current therapy is to remove the diseased tissues and to replace them with inert, synthetic materials that, however, are incapable of replacing the biological function of the lost tissue. Similar to other connective tissue, pulp tissue has the potential to heal; however, to achieve successful pulp–dentine regeneration, a scaffold that mimics the natural extracellular microenvironment is vital. A myriad of polymers have been investigated for this purpose. This chapter will provide an insight into different biomaterials used for fabrication of scaffolds for pulp–dentine regeneration.

This work addresses an important area at the intersection of biology and material science that is significantly underrepresented in the field of study. We draw upon the emerging area coined “synthetic nanobiomimicry” to drive the assembly of hard-to-achieve configurations—the quantum confinement of TiO2 being a case in question. This has far-reaching implications in the exploration and fabrication of low-dimensional materials as a growing need to address future environmental, energy, and biomedical concerns. Biological machineries intrinsic to living systems are synergistically tuned for up- and downscalable growth mechanisms of synthetic materials (e.g., biomineralization) to suit their environmental needs. Imitating intelligent growth processes synthetically to generate nonbiological materials under conditions of confinement is conceptually important. With reference to Chapter 5 in this this contribution, we attempt to bridge the disconnect between how nature assembles biomolecules and biomimetic self-assembly via the growth arrest of a precrystallization amorphous phase leading to nonequilibrium tunable morphologies and their trajectory through the conceptual understanding of protein-folding funnels and biomineralization processes.

Emerging technologies in regenerative medicine are crucial to overcome the organ donor shortage and the limitations in conventional diabetes treatments. A bioengineered pancreas, obtained through the development of a three-dimensional scaffold from both animal and human extracellular matrix, represents the endeavor to provide alternative therapies to pancreatic transplantation. This alternative hopes to provide the needed components, supply a temporary substrate that enhances cellular function, and aid organized development before implantation. This chapter will present an overview of the different techniques used to engineer scaffolds from natural and synthetic materials. We will discuss their main properties and applications in the regenerative medicine pancreatic research field.

Traditional three-dimensional printing technologies, originally meant for synthetic materials, have been adapted for biotechnology and regenerative medicine. The technology works but there is high variability in the resins needed for successful integration with biological components. We define these print resins as bioinks, which encompass printable materials that interface with biocomponents during or after the actual print or are involved in the structural construction of scaffolds that will interface with biocomponents. Although synthetic materials are traditionally accepted as mechanically robust, are finely tunable, and are processed using commercially available methods, natural materials have inherent biochemical cues that induce cell attachment and differentiation. The balance of the strong properties of these materials has led to combined technologies such as co-printing and hybrid bioinks, and the development of specialized resins such cell-laden, sacrificial, and support bioinks. Here, we review the evolution of bioinks from traditional methods and materials to highly complex and specialized resins that have been used successfully for in vitro and in vivo bioengineering applications.

Repairing bone defects is a fairly common surgical procedure. Generally, the patient's own bone is used for repair. However, since complications and costs are high, alternatives have been looked for: allografts, xenografts, or synthetic materials. The present article is devoted to these so-called bone substitute materials, with an emphasis on four aspects: (1) the various materials used for bone substitution, (2) the various formulations that are commercially available (granules, blocks, pastes, cements, membranes), (3) the special architectures used for such materials, and finally (4) the main resorption mechanisms of bone substitutes.

Research developments of materials for tissue engineering applications evolve as new insights into cellular functioning unfold. Bioinertness, the reduction of immunological responses by native tissues against foreign materials, was established during the early stages of biomaterial development. Necessitated bioactivity of materials for enhanced material–tissue interactions produced the discovery of the first synthetic material to bond to living tissues. The emergence of biodegradable polymers instigated the shift from tissue replacement to regeneration where biocompatibility and biomimicry became the core of biomaterial research and tissue engineering strategies. The realized importance of native extracellular matrix (ECM) simulation has expanded the selection of materials to encompass pharmaceutical drugs, bioactive molecules, and cell cultures in addition to natural and synthetic materials. Fabrication techniques of electrospinning and bioprinting have offered prospective for the design of elaborate biomaterials capable of achieving high similarity to ECM at macro-, micro-, and nanoscales. Further research advances in electroactive polymers and piezomaterials are anticipated to open potential for the innovation of sentient bionic and cyborg cellular systems.

Complex interfaces, such as vesicles and biological membranes, and interface-dominated systems, such as foams and emulsions, are central to a vast range of naturally occurring and synthetic materials. In order to characterize their dynamics, it is necessary to cover a wide range of length and time scales. This can only be done by a combination of different techniques. We review here recent results and discuss new trends focusing on two class of techniques: correlation spectroscopies and microscopies, highlighting some examples of their combined use.

Bioceramics prior to the 1970s were employed as implants to perform singular and bio-logically inert roles. The limitations with these synthetic materials as tissue substitutes were emphasized with the growing realization that the cells and tissues of the body perform many other vital regulatory and metabolic roles. Since then, the demands of bioceramics have changed, from maintaining an essentially physical function without eliciting a host response to providing a more positive interaction with the host. This has been accompanied by increasing demands on medical devices that they not only improve the quality of life but also extend its duration. More importantly, the exciting and potential opportunities associated with the use of nanobioceramics as body interac-tive materials, helping the body to heal, or promoting the regeneration of tissues, thus restoring physiological functions. This review covers the type of bioceramics currently used in maxillofacial surgery as well as their production methods and properties. The bioceramics covered include glass ceramics, bioglass, alumina, PSZ and zirconia, and calcium phosphate materials

The term hybrid composites is now becoming of key importance from an economical and ecological compatibility point of view. These are materials made up of two or more different natural and synthetic fibers, reinforced with suitable polymer matrices to form a composite material that include properties comparable to that of manmade materials. Also, in order to keep up with modern technological trends, it has become mandatory to develop materials which are less hazardous to nature so that our environment can be preserved for many more years. This concept has encouraged humans to use hybrid composite materials in applications for daily life. The advantageous properties of these composites, such as cost-effectiveness, recyclability, and biodegradability, have also made these materials a great substitute for synthetic materials which can be used in various applications. In this regard, in this chapter, a collaborative effort has been made to give an overview of different natural and synthetic fibers, their classification, and their applications in various engineering applications, and finally a discussion on hybrid composites and their various properties is included.

This chapter focuses on alignment of fibrous materials using magnetic fields. We show how the diamagnetic nature of most materials makes them amenable to manipulation with magnetic fields. After providing a short introduction on magnetic field alignment theory, we give examples on how this was achieved on not only natural fibers like proteins and polysaccharides but also synthetic materials such as peptide-amphiphile assemblies and liquid-crystal polymers.

As an emerging tool in tissue engineering, 3D bioprinting technology relies heavily on biomaterials as bioink for structural support and sites for attachment of biological and mechanical cues of the laboratory-engineered tissue constructs and organs. While naturally derived materials provide favorable conditions for cell survival, they fall short on the technical requirements of the printing processes and mechanical support for shape maintenance and load bearing that synthetic polymers offer. In this chapter, we will review the various synthetic materials used in bioprinting applications of connective tissue constructs and highlight future research directions.

The treatment of dermal wounds has evolved significantly throughout the history of mankind, from simplistic dressings and sutures to full regeneration of the skin with the aid of cellularized dressings and dermal regeneration templates. The skin is the largest organ in the body and primarily functions as a barrier to external agents. While the skin has impressive inherent self-renewal/repair abilities, assisted skin regeneration is vital for closure in a number of aberrant wound healing conditions (i.e., burns, pressure ulcers, diabetic ulcers, etc.) and in the reduction of scar formation. Currently, there are several types of nonelectrospun skin grafts on the market, but each possesses inherent disadvantages. Electrospinning is an ideal fabrication method for the construction of the skin due to its nonwoven fibrillar structures, potential for cellular infiltration, attachment, and overall structural support. Electrospun scaffolds also allow for fine control over pore sizes and fiber diameters. With regard to skin applications, both synthetic and natural polymers have been utilized in electrospinning. Synthetic materials have controllable degradation rates and mechanical properties, whereas natural materials are biodegradable, biocompatible, and possess cell attachment sites. The electrospinning process also allows for a number of biomolecules to be readily included within the fibrous network to increase scaffold bioactivity. Additives such as Manuka honey or an assorted cytokine and chemokine milieu can be incorporated into these electrospun scaffolds to promote bacterial inhibition and modify the local inflammatory response, respectively. This review provides an overview of various electrospun scaffold fabrication techniques, scaffold compositions, and dopants to enhance wound healing and regeneration.

Native autogenous vessels have served as the gold standard conduit material in the treatment of many vascular diseases. However, a significant percentage of patients lack suitable autogenous vessels for use in vascular interventions. For these patients, alternative grafts comprised most commonly of synthetic polymers demonstrate poor long-term patency rates when bypassing arteries of small caliber. This chapter begins with a discussion of the clinical efficacy of autogenous vessels in comparison to the most commonly utilized synthetic materials used in vascular procedures, expanded polytetrafluoroethylene and polyethylene terepthalate. It then discusses the interactions between the host and the material at circulatory, perivascular, and anastomotic interfaces, which generally account for the inferior performance of currently available synthetic grafts. Finally, it concludes with a discussion of some of the strategies employed to improve the long-term efficacy of synthetic grafts by modulating host–biomaterial interactions, including a description of the methodologies utilized for the construction of tissue-engineered blood vessels.

Many works have been done to improve quality of food needs using novel technology, specially nanotechnology, by the design and production of new nutrition delivery systems. Nevertheless, the quest for targeting and intelligent nutrition delivery systems that are accomplished with controlled released, biocompatibility, and biodegradability properties still remains. However, the efforts have led to the recent delivery systems in micro- and nanoscale so that the particular functionality of them has been illustrated based on nanonutrition delivery systems using various natural and synthetic materials. Among them, biopolymers have revealed the unique ability to presence in the nutrition delivery systems because of their individual biological properties. In this work, we focused on the types of nutrition delivery systems and their mainly physicochemical and physiological features. Also, advantages, disadvantages, and capabilities of the nutrition delivery systems due to their significant characterizations such as biocomplementary with target sites in order to have low toxicity and continued release are investigated.

This chapter explores the definition of a green material and natural versus synthetic materials. It also discusses low-emitting materials such as adhesives and sealants, the harmful effects of toxins, and the potential impact that building materials have on the environment. Characteristics of various flooring systems such as carpet, PVC/vinyl, cork, bamboo, earthen, building materials, and tile are explored. Building elements such as windows, gypsum wall board (drywall), siding, roofing (including green roofs), and wood products (e.g., MDF) are investigated. The reader is then introduced to advanced framing techniques, structural insulated panels (SIPs), insulated concrete forms (ICFs), and concrete applications. A number of green strategies are outlined (facilitates achieving LEED® credits) such as material reuse, construction waste management (to minimize materials going to landfills), material recycling, regional materials, rapidly renewable materials (bamboo, cork, insulation, linoleum, straw bales, wheatboard, wool, etc.), and straw-bale construction. In addition, the importance of using green office equipment that is ENERGY STAR® certified is emphasized. The purpose of forest certification and certified wood is explained as is life cycle assessment (LCA, also known as life-cycle analysis) of building materials and products.

Biomaterials for craniomaxillofacial applications may be derived from purely synthetic materials or from animal or human tissues, and used to preserve, to some degree, native tissue structure, morphology, and esthetics. Their main advantages of synthetic, allo- and xeno- biomaterials are their off-the-shelf availability and lack of donor-site morbidity, which make them invaluable alternatives to autologous tissue reconstruction and augmentation procedures in craniomaxillofacial surgery. The recent decade has been an increasing number of available biomaterials as alternatives to standard reconstruction (eg, autologous bone grafts). This article provides a brief history and overview of biomaterials currently used in craniomaxillofacial bone and soft tissue replacement and augmentation.

The use of synthetic plastic materials has increased at an alarming rate due to unawareness regarding the hazards of plastic debris. Generally, it is used once and then becomes waste, which is the main contributor toward environmental pollution. Therefore natural degradable materials are the substitutes to control the adverse effects of such environmentally risky materials. Moreover, the preparation and use of degradable or decomposable materials are significant to lessen the problems associated with plastic materials. In addition, various recycling methods are also developed to control the growing issue of synthetic materials to convert them into useful and environment-friendly products. However, more efforts are still needed to promote the use of degradable materials and cost-efficient methods for recycling of plastic waste.

Bacterial biohybrids use the energy of bacteria to manipulate synthetic materials with the goal of solving biomedical problems at the micro- and nanoscale. We explore current in vitro studies of bacterial biohybrids, the first attempts at in vivo biohybrid research, and problems to be addressed for the future.

Self-assembly has become a useful way of constructing biomaterials for a variety of applications ranging from cell culture to tissue engineering. Attractive features of self-assembled biomaterials include chemical definition, modularity, stimulus-sensitivity, and the ability to produce complex supramolecular objects from comparatively simple precursors. These aspects also make self-assembly an effective way of bridging the practicality of synthetic materials with the molecular and structural complexity of biologically derived materials. In this chapter, self-assembling strategies are summarized, with particular emphasis on materials employing peptides and proteins as the essential oligomerizing components. Two-dimensional self-assemblies, primarily self-assembled monolayers, are also overviewed. Immune responses to supramolecular biomaterials, advantages that arise from self-assembling approaches, and examples of recent in vivo applications of these materials are additionally discussed.

The enormous growth of nanotechnology paved ways for the development of advanced drug delivery systems having ultraprecision and control over the release of drugs. Different strategies are adopted to ensure targeted and controlled drug delivery, such as encapsulation, biomarkers, and artificial nanocarriers. These nanocarriers may consist of biological materials or chemically synthesized materials or combination of both, such as protein, lipid, chitosan, lactic acid, polymers, fullerenes, and silica. Researchers have been successful in formulating drugs that act as carriers, as well as drugs. The major challenge for any drug delivery system is biocompatibility and acceptability because interaction of synthetic materials with human body cells is entirely different from biological one. In this chapter we elaborate the effect of various drug delivery systems in contrast to their toxicity with a focus on nanocarriers and nanosystems.

The native myocardium perfectly meets the demands of a healthy organism during a whole lifetime. But in case of congenital or acquired heart diseases, the native myocardium has to be surgically replaced by an appropriate substitute – the cardiac patch. The used cardiac patches should therefore feature long-term durability, should preferably be of autologous material to reduce immunogenicity eventually occurring in case of xenogenic substitutes, or should – in case of synthetic materials – behave like its autologous counterpart. In terms of pediatric surgery, patches should also be adaptable with the patient׳s growth to minimize the need of follow-on operations.

Heart valve tissue engineering based on decellularized xenogenic or allogenic starter matrices has shown promising first clinical results. However, the availability of healthy homologous donor valves is limited and xenogenic materials are associated with infectious and immunologic risks. To address such limitations, biodegradable synthetic materials have been successfully used for the creation of living autologous tissue-engineered heart valves (TEHVs) invitro. Since these classical tissue engineering technologies necessitate substantial infrastructure and logistics, we recently introduced decellularized TEHVs (dTEHVs), based on biodegradable synthetic materials and vascular-derived cells, and successfully created a potential off-the-shelf starter matrix for guided tissue regeneration. Here, we investigate the host repopulation capacity of such dTEHVs in a non-human primate model with up to 8 weeks follow-up. After minimally invasive delivery into the orthotopic pulmonary position, dTEHVs revealed mobile and thin leaflets after 8 weeks of follow-up. Furthermore, mild-moderate valvular insufficiency and relative leaflet shortening were detected. However, in comparison to the decellularized human native heart valve control - representing currently used homografts - dTEHVs showed remarkable rapid cellular repopulation. Given this substantial in situ remodeling capacity, these results suggest that human cell-derived bioengineered decellularized materials represent a promising and clinically relevant starter matrix for heart valve tissue engineering. These biomaterials may ultimately overcome the limitations of currently used valve replacements by providing homologous, non-immunogenic, off-the-shelf replacement constructs. © 2013 Elsevier Ltd.

The application of nanotechnology in medicine represents a great opportunity to enhance the effectiveness of currently available medical treatments, especially focused on challenging healthcare issues, such as skin wound regeneration. Hence, in the last few decades, nanobiomaterials have been extensively studied and optimized for the development of nanoscale drug-delivery systems releasing drugs, such as growth factors, cytokines, or antimicrobials, for skin wound repair. In this regard, several natural or synthetic materials have been studied due to their similarities to the skin and biocompatible properties, or due to their antibacterial or antiseptic effect. In addition, materials can also be engineered as scaffolds for the development of novel wound dressings. Thus, this chapter presents an overview of the current nanotechnological approaches used for the controlled release of drugs in the field of skin wound regeneration, particularly emphasizing polymeric and lipid nanoparticles (NPs), silver NPs, nanofibrous structures, nanosheets, and nanohybrids.

Tissue engineering of skin (STE) has advanced greatly over the last 30 years. There is a vast array of skin substitutes now available commercially. The skin is the largest organ in mammals and has numerous functions in the body, such as thermoregulation, barrier protection, and sensation. The need for skin substitutes is thus significant, particularly for large defects from burns, congenital diseases, trauma, and infections. The treatment of wounds and associated complications exceeds $20 billion annually in the United States. Chronic wounds affect 1% of the population at any given time, and often require multiple treatments. In STE, various biological and synthetic materials are combined with in vitro-cultured cells to generate functional tissues, which can obviate the problems associated with using skin grafts.

A large number of additives (stabilizers, preservatives, vitamins, and nutraceuticals) are scarcely soluble in polar media, and therefore poorly mix with aqueous food dispersion. Besides, they are unstable against light, temperature, pH changing, and oxygen. Therefore, design of effective nanocontainers with controlled binding/release functions toward active components remains a challenge in the food industry. The chapter is oriented on the elucidation of recent trends in the field of engineering of delivery and storage systems for food ingredients. According to modern nanotechnological criteria and the green chemistry approach, food formulations tend to be polycomponent and polyfunctional, with natural and low toxic synthetic materials receiving special attention. Several lines of investigations have been reviewed, including the amphiphile- and polymer-based nanocontainers, supramolecular guest–host strategies involving macrocycle platforms, as well as binding/release behavior of loads.