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After the Industrial Revolution, in the 21st century, mankind is facing the harsh test of economic growth and environmental protection. Colorant research contains cross-field creative thinking that has been added to develop our Cultural Creative Industry to reduce the pollution by artificial dyes. The extensive usage of biomaterials is not only for natural dyeing but also for the development of biotechnology and pharmaceutical products to fight viruses.

The fate processes and cellular behavior of stem cells are highly influenced by the microenvironment, termed as microniche. Based on the stem cell source and its potency, it can be differentiated into various cell types and thereby explored for therapeutic application. Recent advances in stem cell research have shown promise in tissue engineering (TE) and regenerative medicine. Moreover, research on biomaterials has progressed from simple scaffolding fabrications to biomimetic complex constructs. The integration of biocompatible, biodegradable biomaterials with stem cells has been explored as a viable choice for enhancing the efficiency of cell grafting as well as promoting specific cell differentiation. Surface functionalization of scaffolds, biofabrication of hydrogels, composite scaffolds and microspheres/microbeads have been designed with biomimetic characteristics for specific tissue requirements. This chapter throws light on the various biomaterial-based systems that serve as stem cell delivery modalities and provide favorable cellular microenvironments for tissue regeneration.

Spinal fusion is commonly used in spinal surgery to treat spinal deformity and degenerative disease. In animal models, two commonly used posterior spinal fusion surgeries are intertransverse process and interbody spinal fusion. These experimental spinal fusions could provide clues for the medical treatment of patients by stem cell therapy, tissue engineering, or gene therapy. They also serve as study models for testing new biomaterials and their derived composites with bioactive factors or cells. In this chapter, the procedure for rabbit experimental posterior intertransverse process spinal fusion and the method to assess the success of this animal model are described.

Surface modification, ie. improving or changing surface characteristics of biomaterials in a controlled way, has been attracting attention in biomaterials research because of the low cost and the versatility. Some applications of surface modifications, such as immobilization of albumin, heparin and poly(ethylene oxides) (PEO) on polymer surfaces, seeding of endothelial cells on blood vessels, forming of self-assembled monolayer model surfaces, binding of phospholipid polar group on dialysis membrane, etc., are discussed in the present paper. Some surface modification techniques and principles are also introduced. Investigations and synthesis of ceramic films, such as TiN, TaN, DLC, C-N, Ta doped TiO₂, and TiO_2-x films. are presented.

Nanomedicine is to apply and further develop nanotechnology to solve problems in medicine, i.e. to diagnose, treat and prevent diseases at the cellular and molecular level. This article demonstrates through a full spectrum of proof-of-concept research, from nanoparticle preparation and characterization, in vitro drug release and cytotoxicity, to in vivo pharmacokinetics and xenograft model, how nanoparticles of biodegradable polymers could provide an ideal solution for the problems encountered in the current regimen of chemotherapy. A system of vitamin E TPGS coated poly(lactic-co-glycolic acid) (PLGA) nanoparticles is used as an example for paclitaxel formulation as a model drug. In vitro HT-29 cancer cell viability experiment demonstrated that the paclitaxel formulated in the nanoparticles could be 5.64 times more effective than Taxol^® after 24 hr of treatment. In vivo pharmacokinetics showed that the drug formulated in the nanoparticles could achieve 3.9 times higher therapeutic effects judged by area-under-the curve (AUC). One shot can realize sustainable chemotherapy of 168 hr compared with 22 hr for Taxol^® at a single 10mg/kg dose. Xenograft tumor model further confirmed the advantages of the nanoparticle formulation versus Taxol^®.

Photochromic materials have attracted much attention recently because of their potential utility in various high-tech applications. In this paper, several photochromic materials containing chitosan polymers and spiropyran groups were synthesized and characterized. The photochromic properties were investigated by UV–Vis spectroscopy. The spiropyran-graft-chitosan owning the nature of both spiropyran and chitosan, may consider as a novel photochromic material for application in intelligent drug delivery system.

A 16-amino acid oligopeptide forms a stable β-sheet structure in water. In physiological solutions it is able to self-assemble to forma macroscopic matrix that stains with Congo red. On raising the temperature of the aqueous solution above 70°C, an abrupt structural transition occurs in the CD spectra from a β-sheet to a stable α-helix without a detectable random-coil intermediate. With cooling, it retained the α-helical form and took several weeks at room temperature to partially return to the β-sheet form. Slow formation of the stable β-sheet structure thus shows kinetic irreversibility. Such a formation of very stable β-sheet structures is found in the amyloid of a number of neurological diseases. This oligopeptide could be a model system for studying the protein conformational changes that occurs in scrapie or Alzheimer disease. The abrupt and direct conversion from a β-sheet to an α-helix may also be found in other processes, such as protein folding and protein–protein interaction. Furthermore, such drastic structure changes may also be exploited in biomaterials designed as sensors to detect environmental changes.

Commercially pure titanium was treated with an H₂O₂/TaC1₅ solution. Thus formed titania gel layer remained amorphous when heated below 200°C and transformed to anatase after heated between 300-600°C. The anatase layers were substantially bioactive to deposit carbonate ion-incorporated apatite after soaked for 1 d in a simulated body fluid (Kokubo’s recipe), while the amorphous layers did not deposit up to 7 d. The apatite particles were preferably nucleated inside the cracks which prevailed in the titania gel layers. After soaking only for 2 d, the specimens were almost completely covered by the apatite. The H₂O₂-treated Ti specimens deposited apatite on both the contact and open surfaces, whereas the NaOH treated Ti specimens only deposited on the contact surfaces. The elimination of peroxide radicals out of titania gel and formation of anatase during heating are considered to be responsible for the improvement of apatite deposition ability.

Tissue engineering utilizes the expertise in the fields of materials science, biology, chemistry, transplantation medicine, and engineering to design materials that can temporarily serve in a structural and/or functional capacity during regeneration of a defect. Hydroxyapatite (HAp) scaffolds are among the most extensively studied materials for this application. However, HAps have been reported to be too weak to treat such defects and, therefore, have been limited to non-load-bearing applications. Recent advancements in nanoscience and nanotechnology have reignited investigation of HAp formation in the nanorange to clearly define small-scale properties of HAp. It has been suggested that nano- HAp may be an ideal biomaterial due to its good biocompatibility and bone integration ability. In this chapter, a new view on nano-HAp particles highlights the importance of size, crystal morphology controls, and composites with other inorganic particles in the application of biomedical material development. We have also reviewed nanosized HAp-based highly porous composite materials used for bone tissue engineering, introduced various fabrication methods used to prepare nHAp/polymer composite scaffolds, and characterized these scaffolds on the basis of their biodegradability and biocompatibility through in vitro or in vivo tests. Finally, we provide a summary and our own perspectives on this active area of research.

With the growth of the construction industry, the role and importance of sustainable construction practices are also increasing. This study reviews the various advancements in the field of bio-based construction materials, including bio-aggregates, bio-binders, and bio-bricks. The origins of our centuries-old construction methods can be found in bio-based concrete materials, which have been revived and modernized to meet the needs of present-day construction. The integration of recovered construction and agricultural wastes plays a significant role in bringing these materials into the competitive building sector, aligning with sustainability goals. This study provides an in-depth examination of the processes and compositions required to achieve the desired strength and durability of bio-based materials. By comprehensively analyzing global research data, this study offers insights into the successful incorporation of biomaterials, emphasizing their potential to reduce carbon emissions and promote the responsible utilization of natural raw materials. This pathway moving toward more sustainable construction practices underscores the environmental benefits of bio-based concrete materials.