The development of novel lightweight material and structural designs has been strongly influenced by considering the interaction between multiple length and time scales within a system. One example is the design of materials for crack resistance on the nanoscale such that their evolution at small scales influences thematerial fracture and fatigue resistance at themacroscale [1–3].Another example is the design of microscale lattice topologies that are being used as “architected materials” which when looked at from a macroscale perspective represent a homogeneous material with specifically designed properties such as increased strength to weight ratio, cooling, and energy absorption [4–6].

Nanotechnology refers to the development of new techniques, materials and devices that have features on a nanometer size scales, generally considered in the 1–100 nm range. The term was popularized in the 1980’s by K. Eric Drexler, especially in his book, The Engines of Creation (Drexler, 1986), but the term was coined in the context of semiconductor technology (Taniguchi, 1974). One goal of nanotechnologists is to design materials that can be created by combining smaller subunits in a deterministic manner, so called bottom-up assembly. Much of the development in nanotechnology has been accomplished by material scientists, chemists and physicists and the first decade of this century has seen many products with materials containing nanometer-scale features enter the market place (Rejeski, 2009). The subfield of bionanotechnology (or nanobiotechnology), the use of biological systems and materials for nanotechnology or to affect biological systems has also been fruitful. From biological molecules to cells, components of living systems have nanometer-scale features that are created from smaller subunits (amino acids, nucleotides, etc.), examples of bottom-up assembly often cited by nanotechnologists as paradigms of what the field should be capable of achieving. Of especial relevance to the research we will be describing in this monograph is bionanotechnology focusing on four areas: 1) Using whole bacteriophages or components as biological sensors; 2) Use of phage display to develop bacteriophage as guides for material synthesis; 3) Development of nanoparticles (quantum dots) with biological activity; and 4) Use of self-assembling biomolecules. This last includes both protein and nucleic acid systems. We review these briefly here but for more thorough discussions see (Hyman, 2012; Mahasneh, 2013; Niemeyer, 2010; Zelzer and Ulijn, 2010). As well, the August 2014 issue of Current Opinion in Biotechnology (volume 28) is focused in part on nanobiotechnology.

Development of a nanomedical product is a complex process that may involve great deal of time, expenditure and resources [119]. Nanomaterials are difficult to handle due to their small size, surface charges and interactive nature. The small size of nanoparticles may result in acceleration or delay in their intended action. They may also accumulate non-specifically in certain tissues after administration. The nanoscale product development process may require various developmental trials, evaluation parameters and feasibility studies. The synthetic process may turn out to be long and tedious requiring number of components to be added as ingredients or intermediates. Their processing and characterization require sophisticated equipment, machinery and instrumentation demanding considerable technical skills and scientific knowledge of the operator. These and various other complexities present challenges such as lower yield, increased cost, difficult scale-up and manufacturing, tedious characterization, special storage requirements, poor stability and complicated regulatory issues [120].

All chemical entities that are developed for drug applications, regardless of whether they include nanoscale materials, possess unique characteristics and properties and therefore can, and do, present the FD A with novel challenges. Other than a comprehensive physicochemical characterization of nanoscale containing drugs, pharmacokinetic and biodistribution studies are crucial to help assess the safety and efficacy as well as to estimate clinical doses, dose linearity and species differences of such products [6]. It is important to note that there is a close relationship between the biodistribution profile and the physicochemical properties of the nanoparticles. Therefore, identification of whether nanoparticles can accumulate in target and non-target tissues is crucial for designing adequate safety studies. Because of the unique features in each product, there may be additional parameters that may require characterization depending on the nanomaterial. Such features have been reported to influence the biodistribution of nanomaterial containing drugs and possibly their safety [150]. Some of the important and critical evaluation parameters that are required for nanoscale product characterization are measurement of particle size, size distribution, shape, surface charge, stability, density, crystallinity, surface characteristics, solubility and aggregation state [151]. The aggregation/agglomeration state is evaluated as any change in the agglomeration may contribute to unpredictable variations in the PK profile [152].

In 2006, United States Food and Drugs Administration (FDA) included nanotechnology in its Critical Task Force and formed a Nanotechnology Task Force to determine the regulatory approaches that would enable to continue the development of innovative, safe and effective FDA-regulated products, which use nanoscale materials ( http://www.fda.gov/nanotechnology/ ). In July of 2007, the task force released its first nanotechnology report in which the task force highlighted scientific and regulatory issues involving nanoscale material containing products. The scientific issues were focused on understanding the interactions of nanoscale materials with biological systems and the adequacy of current testing approaches for assessing safety and quality of products containing nanoscale materials [6].

In this study, nanocrystalline NiAl intermetallic was prepared by mechanical alloying elemental mixture of Ni and Al powders. The phase transformation, morphology of powders, grain size and r.m.s microstrain of powders during milling were determined using XRD combined Rietveld, SEM and TEM analyses. NiAl alloy powders were obtained after a short milling time. Increasing milling time resulted in the alternation of refinement of grain size down to a nanoscale and increase of strain along with the tendency of structure toward amorphization.

There are mainly three sites concerned with tribochemical reactions in a tribological system. Figure 3.1 schematically shows the tribochemical reactions: (i) the contact area under the combined effect of pressure, shear and friction-induced temperature-rise, (ii) the outside of the contact zone, where microplasma can be generated mainly in the case of non-conducting materials in friction processes [1]; and (iii) the very active nascent surfaces created by the wear process, particularly metal surfaces and even on gold [2]. In this section, we will deal with triboinduced chemical reactions occurring in the stressed zone of boundary-lubricated contacts that are directly concerned with friction and wear processes. A rough estimation of the quantity of material concerned by the reaction indicates very small masses, typically between 10 and 100 picograms, depending on the tribofilm thickness and real area of contact. On the other hand, the solicitation time is often very low, typically a few milliseconds, depending on the sliding speed and the contact diameter. The maximum contact pressure is usually calculated to lie between 500 MPa and 1 GPa and the shear rate is generally higher than 10 4 s −1 . Under these conditions, friction-induced chemical reactions will take place in the so-called magma-state [3] and metastable amorphous structures will more probably be generated. The process is mainly governed by nanometer-scale events, and it is correct to note that macrotribology is certainly dependent on nanotribological events. However, it is generally difficult and hazardous to extrapolate directly from micro to macroscale and vice versa.