Nanomaterials platforms

It is possible that surface enhancement effects, similar to the observations made earlier in metal-fluorophore systems [11, 83-85] may occur. Metal surfaces are known to have effects on fluorophores such as increasing or decreasing rates of radiative decay or resonance energy transfer. A similar effect may take place in ZnO nanomaterial platforms. However, decay lengths of fluorescence enhancement observed in the semiconducting ZnO NRs are not commensurate with the length scale seen on metals such as Au or Ag. For effective metal enhanced fluorescence, fluorophores should be placed approximately between 5-20 nm away from the metal surface. However, fluorescence enhancement effect on ZnO NRs is observed even when fluorophores are located well beyond 20 nm away from the NR surface. At the same time, no quenching effec en when they are placed directly onto ZnO NR surfaces. In addition, there overlap between the absorption and emission... 

First, better smart and multifunctional orthopedic nanomaterials with more capabilities are expected. In the near future, nanomaterial platforms are expected that integrate diagnostic, imaging or monitoring, therapeutic, and tissue regenerative abilities and can be minimal-invasively deployed or administrated. Such nanomaterial systems would complete several tasks that are currently performed individually by different materials or devices with better efficacy and safety. In addition, as implied by the example of a smart hip implant in Section 8.1.1, rapid development of N/MEMS may also contribute to the emergence of novel orthopedic implants based on such novel nanomaterials. 

In aspect of chip-based technology, electrochemical genosensors based on different materials and transducers have been recently developed in response to clinical demand of giving promising results [18-25]. Different sensor technologies provide a unique platform in order to immobilize molecular receptors by adsorption, crosslinking or entrapment, complexation, covalent attachment, and other related methods on nanomaterials [5,7,26]. 

Future development of novel aptazyme technologies, in particular, those involving nanomaterials, will continue to drive the fields of diagnostics and biosensing toward more high-throughput platforms, as well as powerful new LOC devices (Alexander, 2007). 

Catalysts were some of the first nanostructured materials applied in industry, and many of the most important catalysts used today are nanomaterials. These are usually dispersed on the surfaces of supports (carriers), which are often nearly inert platforms for the catalytically active structures. These structures include metal complexes as well as clusters, particles, or layers of metal, metal oxide, or metal sulfide. The solid supports usually incorporate nanopores and a large number of catalytic nanoparticles per unit volume on a high-area internal surface (typically hundreds of square meters per cubic centimeter). A benefit of the high dispersion of a catalyst is that it is used effectively, because a large part of it is at a surface and accessible to reactants. There are other potential benefits of high dispersion as well— nanostructured catalysts have properties different from those of the bulk material, possibly including unique catalytic activities and selectivities. 

From the view point of nanoscience, many research efforts have been put forward to achieve simplicity in the steps leading from the material s synthesis to final applications of nanomaterials. Due to the small size inherent to nanomaterials, manipulation and assembly processes following their synthesis are much more complicated and time consuming than their bulk counterparts. Therefore, numerous studies focused on novel synthetic methods which allow spatial and orientational control of nanomaterials during their growth process. These efforts will be discussed more in Section 12.4. These approaches enable the use of nanomaterials directly upon their synthesis, without going through complex and costly fabrication steps to assemble nanomaterials into application-ready devices and platforms. 

SYNTHESIS AND CHARACTERISATION OF ZINC OXIDE NANOMATERIALS FOR BIODETECTION PLATFORMS... 

Although such a variety of synthetic methods can be used to produce ZnO nanomaterials, the following section will provide an overview of synthetic procedures to produce ZnO nanomaterials that are further demonstrated for fluorescence detection of biomolecules [61-65], Specifically, the following section will focus on a gas-phase nthetic route exploiting microcontact-printed catalysts and describe an in situ m od for producing ZnO nanorod (ZnO NR) platforms in an array format The physical and optical properties of as-synthesized ZnO NRs will be also discussed. 

The capability of ZnO nanomaterials for reliable, multipurpose, and multiplexed fluorescence detection of interacting protein molecules is tested with a variety of model proteins [64]. As a proof-of-concept, different pairs of proteins are sequentially introduced to NR platforms and screened for fluorescence. The approach involving ZnO nanostructures in the enhanced fluorescence detection is then extended to identify the presence or absence of multiple protein / protein interactions on the same substrate. In some cases, microfluidic chambers made out of PDMS are used in order to carry out multiple protein interaction assays on the same ZnO NR supports. 

However, the low sensitivity problem of Raman spectroscopy can be overcome by the optical phenomenon called surface-enhanced Raman scattering (SERS), which originates from the conjugation of molecules with the novel metal nanomaterials such as gold or silver. After the first report of such a phenomenon in 1974 [16], several techniques were developed for a wide variety of applications. Current development in nanotechnology has accelerated the researches about SERS to realize accurate, sensitive, selective, and practical sensing platform in several areas including biomolecular detection. 

The use of nanomaterials (i.e., engineered particles or objects with at least one dimension less than 0.1 pm in size) in the research, development, testing and evaluation of new weapon systems and platforms has been ongoing for at least a decade, and the basic understanding of the ecotoxicological effects of nanosized materials is increasing rapidly [2-4], Due to their high specific surface area and chemical... 

Optoelectronic nanodevices that rely on electric field effects in optical absorption and emission provide the ability to be controlled conveniendy using integrated electronic platforms. Semiconductor quantum dots are theoretically expected as an excellent candidate for such optoelectronic nanomaterials to show optical properties strongly dependent on electric field [1]. In the general class of quantum dots, chemically synthesized semiconductor nanocrystals also exhibit electric field effects, for example, as demonstrated in their optical absorption (e.g. the quantum confined Stark effect [2,3]) and in their optical emission as the Stark shift and luminescence quenching [4,5]). 

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