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Femtosecond laser micromachining is a hot topic in the field of micromachining. Femtosecond laser processing of biomacromolecular micro devices has a promising application prospect. The research content of this paper is femtosecond laser micromachining of biomacromolecule materials, aiming at exploring the mechanism of femtosecond laser micromachining. In this paper, the principle of the interaction between laser and polymer materials is briefly expounded, and the photophysical processes such as transition, energy conversion, energy transfer and electron transfer are explained from the molecular orbital, and the mechanism is classified as photothermal and photochemical action, which is manifested as accelerating material's relaxation transformation process and degradation process. The interaction between polymer materials and laser starts from molecules absorbing the energy of photons to complete the transition from ground state to excited state. Different modes of excitation state inactivation correspond to the conversion of light energy into light energy, heat energy or chemical energy. On the one hand, the thermal action leads to the viscoelastic transformation of the material, and the material deforms or flows under the thermoelastic action; on the other hand, the thermal action accelerates the degradation reaction of the polymer material. The carbonyl group on the molecular chain of PMMA and PLA is more likely to reach the excited state, and the chemical properties of the carbonyl excited state determine that the photochemical processes of PMMA and PLA concentrate on the carbonyl group.

Despite the rapid progress of several three-dimensional (3D) printing technologies, there exists a critical barrier in-term of processability of high performance materials. Polyether-ether-ketone (PEEK) is known for its higher mechanical properties, chemical stability, biological stability and biocompatibility suitable for certain biomedical applications. Examining a growing body of scientific literature on 3D printing of biomedical polymers indicates that most of the studies are conducted using biomedical polymers such as poly-carpolactone, poly-lactic acid, poly-glycolic acid, polyethylene and polyurethanes. However, studies on 3D Printing of PEEK is sparse owing to the higher temperatures needed for melting, lacking of availability of suitable feedstock, concerns over poor adhesion between layers, and time consuming and uneconomical processing steps. Given the unique nature of PEEK class of polymers, this manuscript closely examines 3D printability of PEEK for a range of biomedical applications. This manuscript also presents ideas, feasible solutions and enabling scientific mechanisms to improve the 3D printability of PEEK. This article will help the research community to strengthen the conceptual knowledge and insights on the 3D printing of PEEK based medical devices and tools, and future possibilities.

Fast growing applications of 3D printing still lacked with a hurdle of printing high functional executing polymers. Poly-ether-ether-ketone (PEEK) produces excellent mechanical properties, chemical stability, biological stability and biocompatibility, especially employable for clinical applications. Previous literature is on fabrication of biomedical polymers by additive manufacturing (AM) such as poly-carpolactone, poly-lactic acid, poly-glycolic acid, poly-ethylene and polyurethanes. Only few studies are conducted on 3D printing of PEEK is due to its high melting point, non-availability of feed stock and poor properties of printed parts. This present review paper concentrates on printing of porous architecture which will be suitable for various medical applications with the use of the PEEK material.

We developed a Convolutional Neural Network model to identify and classify Airbrushed (alternatively known as Blow-spun), Electrospun and Steel Wire scaffolds. Our model ScaffoldNet is a 6-layer Convolutional Neural Network trained and tested on 3043 images of Airbrushed, Electrospun and Steel Wire scaffolds. The model takes in as input an imaged scaffold and then outputs the scaffold type (Airbrushed, Electrospun or Steel Wire) as predicted probabilities for the 3 classes. Our model scored a 99.44% Accuracy, demonstrating potential for adaptation to investigating and solving complex machine learning problems aimed at abstract spatial contexts, or in screening complex, biological, fibrous structures seen in cortical bone and fibrous shells.

In the past few years, research and the development of biomedical polymers and processing technologies for biomedical applications have received growing attention. Among the most attractive technologies, additive manufacturing (commonly known as three-dimensional printing) is highly suitable for producing sophisticated and tailor-made scaffolds for biomedical applications due its inherent advantages of customizability and the ability to create complex shapes with precision. Moreover, this is a time-saving approach, being far more reproducible than conventional techniques to obtain scaffolds. Additive manufacturing (AM) includes a wide variety of manufacturing techniques and it is being used in personalized prosthetic/implant devices for otorhinolaryngology, dentistry, orthopedics, and craniofacial reconstruction, among others. Tissue engineering and controlled drug-release systems are also important research fields which use AM as a tool for designing accurate, structured, and tailored functional structures. However, there are some limitations for processing new materials using AM techniques. Furthermore, there is an increasing need for new biocompatible and/or bioresorbable materials with different mechanical properties, degradation rates, and surface requirements to be processed for a broad range of applications. In the past years, biocompatible and biodegradable segmented polyurethanes (SPUs) have been investigated for their applications in tissue engineering, controlled drug-release systems, wound dressings, and many biomedical devices. SPU and their composites with poly(ethylene glycol), cellulose, starch, gelatin, alginate, fibrinogen, and collagen, among others, have been explored through different AM techniques for biomedical applications. This chapter aims to review the use of novel AM as microfabrication tools for bioresorbable SPU elastomers and SPU composites. Current advances in 3D printing of SPU are described and commented on. Advantages and shortcomings of the current approaches, as well as future perspectives are outlined. Finally, a vision for future research on this topic is presented.

In the last 10 years, additive manufacturing has progressed from being not just a prototyping technology but a manufacturing technology within the medical manufacturing industry; it has turned many medical manufacturing sectors completely on their heads such as the dental and hearing aid device making industries. 3D printing can create models of high organic intricacy in a relatively short period of time. It has greatly added to the medical industry advancements in visualising and creating complex human or animal anatomies and can be used as an aid for surgical planning and preparation, physician and patient pre-operative/treatment education, medical procedure training and upskilling, medical devices, medical device development, and custom medical device manufacturing. Additive manufacturing (AM) is rapidly growing with advances in new material development, higher resolution, and faster speeds, making it a cost-effective alternative manufacturing solution for many medical applications. The objective of this chapter is to provide some guidelines and considerations of the many steps involved in the manufacturing of biomedical polymers and the main post-processing considerations for individual types of industrial polymer technologies.

Background The worldwide demand for the organ replacement or tissue regeneration is increasing steadily. The advancements in tissue engineering and regenerative medicine have made it possible to regenerate such damaged organs or tissues into functional organ or tissue with the help of 3D bioprinting. The main component of the 3D bioprinting is the bioink, which is crucial for the development of functional organs or tissue structures. The bioinks used in 3D printing technology require so many properties which are vital and need to be considered during the selection. Combination of different methods and enhancements in properties are required to develop more successful bioinks for the 3D printing of organs or tissue structures. Main body This review consists of the recent state-of-art of polymer-based bioinks used in 3D printing for applications in tissue engineering and regenerative medicine. The subsection projects the basic requirements for the selection of successful bioinks for 3D printing and developing 3D tissues or organ structures using combinations of bioinks such as cells, biomedical polymers and biosignals. Different bioink materials and their properties related to the biocompatibility, printability, mechanical properties, which are recently reported for 3D printing are discussed in detail. Conclusion Many bioinks formulations have been reported from cell-biomaterials based bioinks to cell-based bioinks such as cell aggregates and tissue spheroids for tissue engineering and regenerative medicine applications. Interestingly, more tunable bioinks, which are biocompatible for live cells, printable and mechanically stable after printing are emerging with the help of functional polymeric biomaterials, their modifications and blending of cells and hydrogels. These approaches show the immense potential of these bioinks to produce more complex tissue/organ structures using 3D bioprinting in the future.

Biomedical polymers have and still continue to play an important role in how we support and treat patients with various diseases through their use in tissue and blood interacting medical devices and drug delivery systems. Today, a wide variety of blood-contacting devices provide the means for the diagnosis, treatment, and support of life until organ transplantation. Their usage warrants their interaction with cells, bacteria, blood, tissue, and sometimes a combination of these complex living systems and the fates of such interactions are critical for applications including biomimetic surfaces, regenerative medicine, immunomodulation, smart biomaterials for drug delivery, and many more. For blood-contacting devices, their surface interactions with blood mostly lead to blood coagulation, inflammation, device failure, and patient complications. Their lifetimes are thus limited to hours and days due to clot formation. Use on the order of months is however needed for many of these devices including vascular grafts, catheters, artificial lungs, extracorporeal circulation circuits, and dialysis membranes, which rely on the free flow of blood over their surfaces. Clots, however halts this flow and causes the devices to fail. This chapter describes prominent challenges and new directions of hemocompatibility and specifically anticlotting biomaterials research.

The usage of biopolymers in medical and biotechnology fields has become a very promising research area due to the cleaner, safer, and renewable technologies. The biopolymers possess unique properties of biodegradability and biocompatibility which seek the attention of researchers to use these biostable polymers in medical application and has enabled us to develop mechanically stable functional implants with a controlled drug- release surface leading to a great deal of positive health outcomes. These biocompatible biopolymers have a great deal of applications in various medical fields such as gene therapy, stem cell research, scaffold engineering, organ regeneration, regenerative medicine, cancer therapy, heart disease, dental treatments, and so on. Biocompatibilty testing helps us to determine the biological reactions of a human body/animal to a product/device that comes into contact with it for a particular duration of time. Various in vivo polymer biocompatibility testing procedures have been developed which entail the development and extraction of various biopolymers from biological samples and help us in determining the rejection, degradation mechanism of these materials inside the human body. Hence, in this chapter, a detailed description regarding the application of various biopolymers in the medical field and also the various in vivo testing methodologies has been elaborated.

The potential for the clinical application of stem cells in tissue regeneration is clearly significant. However, this potential has remained largely unrealized owing to the persistent challenges in reproducibly, with tight quality criteria, and expanding and controlling the fate of stem cells in vitro and in vivo. Tissue engineering approaches that rely on reformatting traditional Food and Drug Administration-approved biomedical polymers from fixation devices to porous scaffolds have been shown to lack the complexity required for in vitro stem cell culture models or translation to in vivo applications with high efficacy. This realization has spurred the development of advanced mimetic biomaterials and scaffolds to increasingly enhance our ability to control the cellular microenvironment and, consequently, stem cell fate. New insights into the biology of stem cells are expected to eventuate from these advances in material science, in particular, from synthetic hydrogels that display physicochemical properties reminiscent of the natural cell microenvironment and that can be engineered to display or encode essential biological cues. Merging these advanced biomaterials with high-throughput methods to systematically, and in an unbiased manner, probe the role of scaffold biophysical and biochemical elements on stem cell fate will permit the identification of novel key stem cell behavioral effectors, allow improved in vitro replication of requisite in vivo niche functions, and, ultimately, have a profound impact on our understanding of stem cell biology and unlock their clinical potential in tissue engineering and regenerative medicine.

Polymeric biomaterials have significant impact in the aged society. Biocompatible and biodegradable polymers have emerged during the past decades to promise extraordinary breakthroughs in a wide range of diagnostic and therapeutic medical devices. Understanding and controlling the interfacial interactions of the polymeric biomaterials with biological elements, such as water, ions, proteins, bacteria, fungai and cells, are essential toward their successful implementation in biomedical applications. Here we highlight the recent developments of biocompatible and biodegradable fusion polymeric biomaterials for medical devices and provide an overview of the recent progress of the design of the multi-functional biomedical polymers by controlling bio-interfacial water structure through precision polymer synthesis and supramolecular chemistry. Biocompatible and biodegradable polymers have emerged during the past decades to promise extraordinary breakthroughs in a wide range of diagnostic and therapeutic medical devices. Understanding and controlling the interfacial interactions of the polymeric biomaterials with biological elements are of essential towards their successful implementation in biomedical applications. Here, we highlight recent developments of biocompatible and biodegradable fusion polymeric biomaterials for medical devices and overview of the recent progress of the design of the multi-functional biomedical polymers by controlling biointerfacial water structure through precision polymer synthesis and supramolecular chemistry.

The paper is a literature review concerning the preparation and biomedical properties of polyurethanes for pharmaceutical applications. The basic uses of polyurethanes in pharmacy comprise modern drug formulations (including therapeutical systems, carriers and conjugates). Clinical studies indicate that the application of polymer—drug conjugates has a beneficial effect on the therapy efficacy. The introduction of such conjugates into the body results in an increase in drug therapeutic index as an effect of increased drug availability in the affected areas,while at the same time reducing systemic exposure to the drug.Owing to the application of polyurethane conjugates, it is also possible to reduce the side effects and toxicity of drugs. It is expected that the studies on macromolecular drug conjugates (including polyurethanes) will stimulate the development of modern forms of drugs and broadly defined medicinal chemistry.

Background: Although various types of materials have been used widely in dialyzers, most biomaterials lack the desired functional properties to interface with blood and have not been engineered for optimum performance. Therefore, there is increasing demand to develop novel materials to address such problems in the dialysis arena. Numerous parameters of polymeric biomaterials can affect biocompatibility in a controlled manner. The mechanisms responsible for the biocompatibility of polymers at the molecular level have not been clearly demonstrated, although many theoretical and experimental efforts have been made to try and understand them. Moreover, water interactions have been recognized as fundamental for the blood response to contact with polymers. Summary: We have proposed the ‘intermediate water' concept and hypothesized that intermediate water, which prevents the proteins and blood cells from directly contacting the polymer surface, or nonfreezing water on the polymer surface, plays an important role in the biocompatibility of polymers. This chapter provides an overview of the recent experimental progress of biocompatible polymers measured by thermal, spectroscopic, and surface force techniques. Additionally, it highlights recent developments in the use of biocompatible polymeric biomaterials for dialyzers and provides an overview of the progress made in the design of multifunctional biomedical polymers by controlling the biointerfacial water structure through precision polymer synthesis. Key Messages: Intermediate water was found only in hydrated biopolymers (proteins, polysaccharides, and nucleic acids, DNA and RNA) and hydrated biocompatible synthetic polymers. Intermediate water could be one of the main screening factors for the design of appropriate dialyzer materials.

Recent developments in polymer-based controlled delivery systems have made a significant clinical impact. The second Symposium on Innovative Polymers for Controlled Delivery (SIPCD) was held in Suzhou, China to address the key challenges and provide up-to-date progress and future perspectives in the innovation of polymer-based therapeutics. At SIPCD, a stimulating panel discussion was introduced for the first time on “What is the future of nanomedicine?” This report highlights the most recent research and developments in biomedical polymers and nanomedicine made by 29 invited scientists from around the world, as well as important issues regarding clinical advancements of nanomedicine conferred during the panel discussion.

The purpose of this communication is to present the author's perspectives on the future of biomedical materials that were presented at the Larry L. Hench Retirement Symposium held at Imperial College, London, in late September 2005. The author has taken a broad view of the future of biomedical materials and has presented key ideas, concepts, and perspectives necessary for the future research and development of biomedical polymers and their future role as an enabling technology for the continuing progress of tissue engineering, regenerative medicine, prostheses, and medical devices. This communication, based on the oral presentation, is meant to be provocative and generate discussion. In addition, it is targeted for students and young scientists who will play an ever-increasing role in the future of biomedical materials.

This work presents the challenges and directions in biomaterials research. Biomaterials have been playing an important role in the treatment of disease and the improvement of healthcare. Metals were used in dentistry while synthetic polymers have been used for vascular grafts; polymethylmethacrylate and stainless steel have been used in total hip replacements. Controlled drug delivery systems largely involve biomedical polymers and are used by tens of million of people annually. Furthermore, in tissue engineering, by combining polymers with mammalian cells, it is now possible to engineer skin for patients who have burns or skin ulcers. Until recently, biomaterials were adopted from other areas of science and technology with little design for biomedical use, which did not help to completely resolve issues in biocompatibility, mechanical properties, degradation, etc. Modern biomaterial science is laying the foundation for a fundamental design by taking into consideration cell-matrix interactions, cellular signaling processes, and developmental biology. Concepts that are shaping future directions are biomaterials for specific biomedical applications made from naturally occurring or man-made building blocks or novel applications for biomaterials, such as diagnostics and array technologies.

Nanofibers have been of great interest in the recent years, because of its huge potential to diverse fields, especially in biomedical applications. The most favorable feature is the dimension of nanofibers that resembles that of the natural collagen fibrils in nano scale. They thus provide extremely large surface area to volume ratio as compared to microfibers. Electrospinning is the most preferred method in producing nanofibers from polymers. In this chapter, an overview of polymer nanofibers is stated, specifically focusing on the electrospun nanofibers used in biomedical applications. Along with a brief description of history, principle, and operating parameters of electrospinning process, examples of specific functionalities are introduced through bulk and surface modifications of nanofibers. In addition, a broad range of biomedical application includes tissue-engineered scaffolds, wound dressings, medical device and implants, controlled drug release, and other applications in biosensor, biocatalyst, and bioenzyme. With the rapidly growing demand nanofibers should find its enormous potential for the future development of nanoscience and biomedicine.

Recently polymeric materials have gained tremendous attention in a wide variety of applications spanning from electronics to environmental and biomedical fields. In this paper, current in vitro methods for polymers biocompatibility assessment are reviewed in combination with new concepts and techniques that appear promising for the development and improvement of in vitro methods with the purpose of reducing animal experimentation. The utilization of medical devices, for example, has always been subordinate to the assessment of their biocompatibility. This aspect, as well as the methods for evaluating biocompatibility have changed over the years as a result of new developments in cell biology that have revolutionized in vitro techniques for assaying polymeric materials for bioapplications.

The background, formulation, available forms, and clinical applications of a biomaterial have been presented to amplify the materials broad spectrum of used in oral and maxillofacial surgery. These forms of therapy provide a wider area of practice as well as a greater level of patient satisfaction.

This paper deals with the various types of polymers, used in the fabrication of medical devices, their diversity of applications and toxic hazards which may arise out of their application. The potential toxicity of monomers and the various additives used in the manufacture of biomedical polymers have been discussed along with hazards which may arise out of processing of devices such as sterilization. The importance of quality control and stringent toxicity evaluation methods have been emphasised since in our country, at present, there are no regulations covering the manufacturing and marketing of medical devices. Finally the question of the general and subtle long term systemic toxicity of biomedical polymers have been brought to attention with the suggestion that this question needs to be resolved permanently by appropriate studies.

Europe is becoming a center for the development of biomaterials, as the industry becomes increasingly ‘globalized’. From a materials perspective, it is clear that all the activity in the biornaterials/medical device industry is in polymers, and bioabsorbable polymers represent a significant market opportunity. To make profits in biomedical polymers, a chemical company must participate in the ‘value added chain’, whereby the supplier of the chemical (polymer) participates in the profits of the sale to the end-user.

The field of biomedical polymers continues to show steady growth in both the basic research and applications areas. The only limit to the suggested uses of polymers in medicine seems to be a limit in our imagination. Some recent popular articles suggest that nearly all parts of the human body could be replaced by some type of a plastic and/or metal device (1,2). Many major problems remain to be solved before this vision could become fact, however. A large number of recent surveys and books attest to the great interest in this important field of science (3–31). These books but scratch the surface and hundreds of articles are published each year in a variety of journals including such specialized ones as the Journal of Biomedical Materials Research and the Transactions of the American Society of Artificial Internal Organs. Courses in the field of biomedical polymers and biomaterials are now offered at many different universities (32).