Biologically active gases

GAs such as GA20 [9]. To date, none of the mutants with increased elongation in peas has been proven to result from the overproduction of biologically-active GAs [7, 19]. 

In terms of biologically active GAs, the suspensor shows the same qualitative spectrum and about the same amount (about 100 fig g fw) at stages A and B, with the exception of GAg. The suspensor at this stage is metabolically very active only when it starts to degenerate are some of the biologically active GAs (probably GA and/or GA5) converted to GAg which is 2-hydroxylated and not biologically active. 

In addition to the far- and near-field studies on natural analogues mentioned above, the studies on radionuclide migration mechanisms (e.g., solubility, specia-tion, sorption, adsorption, ion exchange, precipitation, matrix diffusion, colloid, redox front, biological activity, gas generation) are also regarded as the natural analogue studies. 

GAs or other methods from evolutionary computation are applied in various fields of chemistry Its tasks include the geometry optimization of conformations of small molecules, the elaboration of models for the prediction of properties or biological activities, the design of molecules de novo, the analysis of the interaction of proteins and their ligands, or the selection of descriptors [18]. The last application is explained briefly in Section 9.7.6. 

Potcntiomctric Biosensors Potentiometric electrodes for the analysis of molecules of biochemical importance can be constructed in a fashion similar to that used for gas-sensing electrodes. The most common class of potentiometric biosensors are the so-called enzyme electrodes, in which an enzyme is trapped or immobilized at the surface of an ion-selective electrode. Reaction of the analyte with the enzyme produces a product whose concentration is monitored by the ion-selective electrode. Potentiometric biosensors have also been designed around other biologically active species, including antibodies, bacterial particles, tissue, and hormone receptors. 

Present research is devoted to investigation of application of luminol reactions in heterogeneous systems. Systems of rapid consecutive reactions usable for the determination of biologically active, toxic anions have been studied. Anions were quantitatively converted into chemiluminescing solid or gaseous products detectable on solid / liquid or gas / liquid interface. Methodology developed made it possible to combine concentration of microcomponents with chemiluminescence detection and to achieve high sensitivity of determination. 

There is considerable experimental evidence indicating loss of biological activity of macromolecules such as globular proteins and enzymes at gas-Hquid [57], liquid-solid (Fig. 26) [107] and liquid-liquid [108] interfaces. The extent of inactivation has been shown to be strongly influenced by the prevailing flow field and by, many other factors including the presence and/or absence of additives and contaminants and the type of solid surfaces (Figs. 27 and 28) [107]. 

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