System solid-phase reagents

Barsukov V.Z., Khomenko V.G., Chivikov S.V., Barsukov I.V., Motronyuk T.I. On the faradaic and non-faradaic mechanisms of electrochemical processes in conducting polymers and some other reversible systems with solid-phase reagents. Electrochim. Acta 2001 46 4083-94... 

The last of these systems has been adapted to a solid-phase reagent system (Equation 4.9) that obviates the problems associated with byproduct removal, and the by-product may be recycled (treatment with phosgene) to regenerate the active insoluble reagent.1819... 

A derivative of umbelliferyl-p-galactoside serves as a fluorogenic substrate for E. coli (3-galactosidase in this system and solid-phase reagent strips based on this method have been developed. 

S50 Thomas, L., Plischke, W. and Storz, G. (1982). Evaluation of a quantitative solid phase reagent system for the determination of blood analytes. Ann. Clin. Bio-chem. 19, 214-223. 

Burd, J.F., Ellis, P.B., Greenquist, A.C., Li, T.M., Morris, D.L., Rupchock, P.A., Sommer, R.G., Tyhach, R.J., Walter, B. and Zipp, A.P. (1983). Measurement of theophylline with the substrate-labeled fluorescent immunoassay and apoenzyme reactivation immunoassay system in solution and in solid phase reagent strips. In Avrameas, S. et al. (Eds), Immunoenzymatic Techniques Proc. 2nd Int. Symp. Immunoenzymatic Techniques, Cannes, 16-18 March. Elsevier Science Publishers, Amsterdam, pp. 239-246. 

S244 Szekeres, T., Legenstein, E. and Kremser, K. (1989). Evaluation of an improved version of the Seralyzer III solid phase reagent system. Biochim. Clin. 13, Suppl. 1/8, 151, Abstr. A 26. 

Figure 5 Schematic diagram of a solid phase reagent system for glucose measurement (Ektachem System).

Single-line FIA system with solid-phase reagents for the indirect determination of cyanide by flame atomic absorption spectrometry. IV injection valve SPR AgX (where X is Cl. Br and D solid-phase reactor. 

The FIA system manifold for indirect determination of cyanide based on the formation of soluble complexes in a small column packed with solid-phase reagent (SPR) is given in Figure 9.1. 

In these systems, solid enzyme preparations (e.g. lyophilized or immobilized on a support) are suspended in an organic solvent in the presence of enough aqueous buffers to ensure catalytic activity. Although the amount of water added to the solvent (as a rule of thumb <5% v/v) may exceed its solubility in that solvent, a visible discrete aqueous phase is not apparent because part of it is adsorbed by the enzyme. Therefore, the two phases involved in an organic solvent system are a liquid (bulk organic solvent and reagents dissolved in it) and a solid (hydrated enzyme particles). 

The process known as SPREAD (Surface Promoted Replication and Exponential Amplification of DNA Analogues) attempts to reach the target, striven for by many researchers, of an exponential proliferation of biomolecules in model systems. As already mentioned, product inhibition (e.g., by dimerisation of the new matrices to give C2) only allowed parabolic growth. In the SPREAD process, both solid phase chemistry and feeding have a positive effect on the synthesis. Thus, no separation processes are required, as excess reagents can be removed just by washing. The synthetic process consists of four steps ... 

The theory on the level of the electrode and on the electrochemical cell is sufficiently advanced [4-7]. In this connection, it is necessary to mention the works of J.Newman and R.White s group [8-12], In the majority of publications, the macroscopical approach is used. The authors take into account the transport process and material balance within the system in a proper way. The analysis of the flows in the porous matrix or in the cell takes generally into consideration the diffusion, migration and convection processes. While computing transport processes in the concentrated electrolytes the Stefan-Maxwell equations are used. To calculate electron transfer in a solid phase the Ohm s law in its differential form is used. The electrochemical transformations within the electrodes are described by the Batler-Volmer equation. The internal surface of the electrode, where electrochemical process runs, is frequently presented as a certain function of the porosity or as a certain state of the reagents transformation. To describe this function, various modeling or empirical equations are offered, and they... 

In chemical syntheses under the action of microwave irradiation the most successful applications are necessarily found to be the use of solvent-free systems [6], In these systems, microwaves interact directly with the reagents and can, therefore, drive chemical reactions more efficiently. The possible acceleration of such reactions might be optimum, because they are not moderated or impeded by solvents. Reactions on solid mineral supports and, in turn, the interaction of microwaves with the reagents on the solid phase boundary, which can substantially increase the rate of the reactions, are of particular interest [7]. 

The RPIA technology has been enhanced in the Stratus CS system by utilization of a dendrimer-antibody complex in which the analyte-specific capture antibody is covalenty coupled onto a dendrimer. The test packs in the Stratus CS system include dendrimer-capture antibody complex reagent, the alkaline phosphatase labeled antibody conjugate reagent, the substrate-wash reagent and a piece of glass fiber filter paper as the solid phase. Preparation and unique properties associated with these dendrimer-coupled antibody complexes are described below. 

The requirements for solid-phase synthesis are diverse. The support must be insoluble, in the form of beads of sufficient size to allow quick removal of solvent by filtration, and stable to agitation and inert to all the chemistry and solvents employed. For continuous-flow systems, the beads also must be noncompressible. Reactions with functional groups on beads imply reaction on the inside of the beads as well as on the surface. Thus, it is imperative that there be easy diffusion of reagents inside the swollen beads and that the reaction sites be accessible. Accessibility is facilitated by a polymer matrix that is not dense and not highly functionalized. A matrix of defined constitution allows for better control of the chemistry. Easier reaction is favored by a spacer that separates the matrix from the reaction sites. Coupling requires an environment of intermediate polarity such as that provided by dichloromethane or dimethylformamide benzene is unsuitable as solvent. 

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