Mechanical immobilization

D.R. Shankaran and S.S. Narayanan, Amperometric sensor for hydrazine determination based on mechanically immobilized nickel hexacyanoferrate modified electrode. Russian J. Electrochem. 37, 1149-1153 (2001). 

Meyer B, Ziemer B, Scholz F (1995) In Situ X-ray diffraction study of the electrochemical reduction of tetragonal lead oxide and orthorhombic Pb(OH)Cl mechanically immobilized on a graphite electrode. J Electroanal Chem 392 79-83. 

Only within the past two decades has the great potential of electrochemical studies of single micro/nanoparticles (or of their assemblies) been truly realized, and important advances have been made subsequently, both with respect to the experiments as well as to the theoretical basis of this topic. Among the different experimental approaches developed to assess the electrochemistry of micro/nanoparticles, that of mechanically immobilizing assemblies of micro/nanoparticles onto inert electrodes has proved to be especially advantageous, for the following reasons ... 

Although the first reports of this approach involved studies with metal alloys [3] and minerals [4], within a few years the technique has been extended to a wide variety of research areas. As these findings have been summarized in several reviews [5-8] and also in a monograph [9], attention will be focused here on more recent developments, notably on the mechanical immobilization of particles on electrodes. Today, a huge amount of information is available for electrochemical systems comprising particles enclosed in polymer films or other matrices (see Refs [10-16]). Originally, the main aim of such particle enclosure was to achieve specific electrode properties (e.g., functionalized carbon/polymer materials as electrocatalysts [17, 18] solid-state, dye-sensitized solar cells [19]), rather than to study the electrochemistry of the particles. This situation arose mainly because the preparation of these composites was too cumbersome for assessing the particles properties. The techniques also suffered from interference caused by the other phases that constituted the electrode. 

The basic technique of mechanical immobilizing particles has been described in detail elsewhere [7, 9], and needs not be repeated at this stage. 

Here, we shall discuss some new developments relating to the quantitative evaluation of data and, for the sake of completeness, also briefly mention previously developed approaches. As the technique of mechanical immobilizing particles on electrode surfaces does not allow the amount of deposited particles to be controlled, the following approaches for quantitative evaluation have been developed ... 

In another report from the same group, different anthraquinone-based dyes were studied using square-wave voltammetry following the mechanical immobilization of microparticles on the surface of graphite/polyester composite electrodes [63]. 

Osseointegration A term developed by RI. Branemark and his colleagues indicating the ability of host bone tissues to form a functional, mechanically immobile interface with the implant. Originally described for titanium only, several other materials are capable of forming this interface, which presumes a lack of connective tissue (foreign body) layer. 

Moreover, most researchers agree that protection by compounds such as lactose and trehalose depends on the formation of an amorphous phase with the protein [15], The proteins are mechanically immobilized in the glassy, solid matrix during dehydration. The restriction of translational and relaxation processes is thought to prevent protein unfolding, and spatial separation between the protein molecules (i.e dilution of protein molecules within the glassy matrix) is proposed to prevent aggregation [12],... 

Proponents of one mechanism state that proteins are simply mechanically immobilized in the glassy, solid matrix during dehydration... 

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