Preparation, Structural Characterization, and Biomedical Applications of Gypsum-Based Nanocomposite Bone Cements

Hard tissues are natural nanocomposites comprising collagen nanofibers that are interlocked with hydroxyapatite (HAp) nanocrystallites. This mechanical interlocking at the nanoscale provides the unique properties of hard tissues (bone and teeth). Upon fracture, cements are usually used for treatment of simple fractures or as an adhesive for the treatment of complicated fractures that require the use of metallic implants. Most of the commercially available bone cements are polymer-based, and lack the required bioactivity for a successful cementation. Besides calcium phosphate cements, gypsum is one of the early recognized and used biomaterials as a basi for a self-setting cementation. It is based on the controlled hydration of plaster of Paris at room temperature and its subsequent conversion to a self-setting solid gypsum product. In our work, we have taken this process further towards the development of a set of nanocomposites that have enhanced bioactivity and mechanical properties. This chapter will outline the formation, characterization, and properties of gypsum-based nanocomposites for bone cement applications. These modified cements can be formulated at room temperature and have been shown to possess a high degree of bioactivity, and are considered potential candidates for bone fracture and defect treatment.

Novel Applications of Nanoparticles in Nature and Building Materials

Nanoparticles are assemblies of atoms in the size range less than 100 nanometers. At these length scales, the properties of particles may deviate significantly from those of the equivalent bulk material indicating that changes in physical and chemical properties of materials depend on the dimensions of the particle. The presence of mineral nanoparticles has been reported in a range of natural environments. Such nanoparticles can arise from a variety of mechanisms, including chemical weathering processes, precipitation from relatively saturated solutions in hydothermal and acid mine drainage environments, evaporation of aqueous solutions in soils, and biological formation by a variety of different microorganisms. Furthermore, recent increased applications of nanoparticles in different types of industries, including construction and building material manufacturing, have caused prevalent occurrences of different types of synthetic nanoparticles in the environment. In this chapter, a comprehensive reviews on occurrences and observations of naturally and anthropogeniccally generated nanoparticles in the environment and their characterization techniques will be discussed along with directions and suggestions for the future research topics and areas for nanomaterials.

Perspectives of Nano-Materials and Nanobiosensors in Food Safety and Agriculture

Nanobiosensor is one type of biosensor made up with usage of nanomaterials i.e., nanoparticles and nanostructures. Because of the nanomaterials’ unique properties such as good conductivity, and physicochemical, electrochemical, optical, magnetic and mechanical properties, Nanobiosensors are highly reliable and more sensitive in biosensing approaches over conventional sensors which is having various limitation in detection. Quantum dots, nanotubes, nanowires, magnetic and other nanoparticles enhance sensitivity and lower limit of detection by amplifying signals and providing novel signal transduction mechanisms enable detection of a very low level of food contaminants, pesticides, foodborne pathogens, toxins and plant metabolites. Nanobiosensors are having a lot of scope in sustainable agriculture because of its detecting ability i.e., sensing changes occurred in molecular level. So it can be utilized to find out the variations or modification of plant metabolities, volatiles, gas exchange, hormonal and ion concentration etc. which are the indicators of various harsh environmental stresses (abiotic), biotic and physiological stress. Identification of the stress in the starting stage itself will help us to avoid intensive plant damage and prevent yield losses created by the stress. Nanosensors can be used in smart farming, in which all the environmental factors related to plant growth like temperature, water, pH, humidity, nutritional factor etc. are measured and precaution taken to control the factors which reduce the crop production with the help of IOT platform, thereby enhance the productivity. In this review, discussed about nanobiosensors for detection of food contaminants and various application and its potential in agriculture.

Ti3C2 MXene-Based Nanobiosensors for Detection of Cancer Biomarkers

This chapter provides information about basic properties of MXenes (2D nanomaterials) that are attractive for a design of various types of nanobiosensors. The second part of the chapter discusses MXene synthesis and various protocols for modification of MXene making it a suitable matrix for immobilization of bioreceptors such as antibodies, DNA aptamers or DNA molecules. The final part of the chapter summarizes examples of MXene-based nanobiosensors developed using optical, electrochemical and nanomechanical transducing schemes. Operational characteristics of such devices such as sensitivity, limit of detection, assay time, assay reproducibility and potential for multiplexing are provided. In particular MXene-based nanobiosensors for detection of a number of cancer biomarkers are shown here.