Deposition approaches, future applications

One solution to this problem is to make a restricted deposit of the cell in a public depository, which provides a unique accession number identifying the deposit. By agreement with the depository, the restriction is lifted in the future, for example, when a patent issues referring to the cell. The applicant can then meet the disclosure requirement by providing the deposit s accession number in the specification. This approach works best if only one country is involved but does not work as well with multiple international filings, as the patent office in each country may have its own rules as to what constitutes an acceptable depository, acceptable restrictions on access to the public, and so on. 

Mass amplification is another strategy to increase the mass sensitivity of a standard QCM device and crystal. Such approaches commonly involve enzymatic catalysis to greatly increase either the rates of electron transfer processes in EQCM applications or to increase rates of insoluble mass deposition as the product of an enzymatic reaction [157-159]. However, mass amplification can also involve the use of larger mass objects binding to the QCM crystal, such as gold particles. We expect that future studies will continue to adapt these general mass amplification strategies to specific systems. 

Looking to the future, this capillary-assisted bipolar electrodeposition can be generalized to other types of nanoobjects and also deposits of a very different nature such as other metals, semiconductors, or polymers. The approach, therefore, opens up the way to a whole new family of experiments leading to complex nano-objects with an increasingly sophisticated design allowing original applications. 

Label-free impedance immunosensors have been developed, but in general these methods may require additional amplification to improve sensitivity [57,58]. Nevertheless, a capacitance method using a ferri/ferrocyanide probe and a potentiostatic step approach gave DL 10 pg mL (500 fM) for lL-6 in buffer [59]. Optimization of experimental protocols in flow injection impedance spectroscopy led to sensitivity in the low aM range for interferon-y in buffer [60]. Sensitivities have been enhanced using metal nanoparticle labels or AuNP labels that catalyze subsequent Ag deposition [57]. These methods may be promising for future point-of-care applications if NSB from non-analyte proteins in the patient samples can be minimized. 

However, to be able to introduce further functionality, additional synthesis steps on the structured electrodes could be performed. Branching of primary CNTs grown on graphite foil with secondary nanotubes has been demonstrated by Li et al. and Xia et al. [153, 154], resulting in the so-called hierarchically structured electrodes with high electrical conductivity. In a follow-up study, this concept has been transferred to hierarchically structured electrodes grown on carbon cloth, which is frequently used as GDL in fuel cell electrodes. After Pt deposition onto the carbon cloth/carbon fiber/CNT composites, reasonable activity for ORR was obtained [155]. The application of similar structures in fuel cells has also been reported and makes this approach a promising concept for the immediate future [156,157]. 

If the field of nanotechnology is aimed to grow in the future where metallic nanoparticles find realistic applications, both galvanic displacement and electroless deposition with reducing agents open a tremendous window for future studies of the kinetics and mechanisms of these processes. This approach could lead to the successful production of desired sizes and shapes of the required nanoparticles. 

Based on its early adoption into the European market, DEF metered SCR has become the preeminent global NO reduction technology. Lessons learned from on-road applications should be incorporated into nonroad applications as well as future high efficiency SCR systems. In order to meet these new system requirements, a structured approach to SCR integration should be taken (as outlined above), which has been proven through many applications that are in production globally and supported by the practical examples provided by Ford Motor Company. By following a structured approach, superior NO reduction performance and robust deposit response can be achieved. 

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