Solid phase, second

The various methods utilizing a second antibody for the purpose of separation can be divided into four different types. These are post-precipitation (the most common method), primary antibody pre-precipitation (formation of a precipitate of first and second antibody before adding to the assay vessel), solid phase (second antibody conjugated to an inert solid matrix), and nonimmune globulin pre-precipitation (a new method to be described here). 

The traditional radioimmunoassay (RIA) for TSH was based on competition between endogenous and radiolabeled hormone for bmding sites on a fimited amount of antibody. Separation of antibody-bound and free radioligands was conveniently performed by double-antibody precipitation (enhanced by the addition of polyethylene glycol) or by using a solid-phase, second-antibody procedure. The amount of labeled TSH bound to the antibody was inversely related to the amount of unlabeled TSH present in the serum specimen. 

Owens SM, McBay AJ, Reisner HM, Perez-Reyes M (1981) 125 1 radioimmunoassay of delta-9-tetrahydrocannabinol in blood and plasma with a solid-phase second-antibody separation method. Clin Chem 27 619-624... 

Radio-immunoassay for clonidine in human plasma and urine using a solid phase second-antibody separation was studied by Farina et al. (19). In which... 

To cause an appreciable change in the dimensions (cross section) of the solid object, a considerable amount of the liquid medium is necessary. Since this type of interaction process is volume based, it is characterized by a rather low rate of proliferation of the chemical reaction between the solid and the medium into the bulk of a solid phase. Second, the degrading action of the medium is amplified with an increase in temperature. 

The particles exhibit low physical adsorption of labelled ligands (low non-specific binding). The new solid-phase second antibody obtained with monodisperse particles is more effective and gives more reliable results than commercially available DASP based on cellulose derivatives. The overall performance of the immunoassay for CEA... 

Two approaches have been used to separate the analyte from its matrix in particulate gravimetry. The most common approach is filtration, in which solid particulates are separated from their gas, liquid, or solid matrix. A second approach uses a liquid-phase or solid-phase extraction. 

Lateral density fluctuations are mostly confined to the adsorbed water layer. The lateral density distributions are conveniently characterized by scatter plots of oxygen coordinates in the surface plane. Fig. 6 shows such scatter plots of water molecules in the first (left) and second layer (right) near the Hg(l 11) surface. Here, a dot is plotted at the oxygen atom position at intervals of 0.1 ps. In the first layer, the oxygen distribution clearly shows the structure of the substrate lattice. In the second layer, the distribution is almost isotropic. In the first layer, the oxygen motion is predominantly oscillatory rather than diffusive. The self-diffusion coefficient in the adsorbate layer is strongly reduced compared to the second or third layer [127]. The data in Fig. 6 are qualitatively similar to those obtained in the group of Berkowitz and coworkers [62,128-130]. These authors compared the structure near Pt(lOO) and Pt(lll) in detail and also noted that the motion of water in the first layer is oscillatory about equilibrium positions and thus characteristic of a solid phase, while the motion in the second layer has more... 

The second kind of interaction takes place between solids and as a pure solid phase interaction, does not release any C02. 

Two observations on the correlations can be made. First, these results tend to invalidate one of the major objections to the application of the thermal-ignition theory to composite propellants, namely that heterogeneous interfacial reactions within the solid phase are not possible. Secondly, the effect of pressure on propellant ignitability can be qualitatively explained. 

The gas-liquid-particle processes considered in this paper may be grouped into two major classes. In the first, components of all three phases participate in the chemical reaction. In the second, components of only the gaseous and the solid phases participate in the chemical reaction, the liquid phase functioning as a chemically inactive medium for the transfer of momentum, heat, and mass. Important examples of these two types of processes are described, respectively, in Sections II,A and II,B. 

P8.4 The (solid + liquid) phase diagram for (.Yin-C6Hi4 + y2c-C6Hi2) has a eutectic at T = 170.59 K and y2 = 0.3317. A solid phase transition occurs in c-CftH at T— 186.12 K, resulting in a second invariant point in the phase diagram at this temperature and. y2 — 0.6115, where liquid and the two solid forms of c-C6H12 are in equilibrium. A fit of the experimental... 

Silicon is the second most abundant element in the Earth s crust. It occurs widely in rocks as silicates, compounds containing the silicate ion, Si032, and as the silica, Si02, of sand (Fig. 14.33). Pure silicon is obtained from quartzite, a granular form of quartz (another solid phase of SiOz), bv reduction with high-purity carbon in an electric arc furnace ... 

This sample preparation involved, firstly, an extraction and the elimination of the solid matrix by filtration and, secondly, a concentration procedure employing a solid phase extraction cartridge. The compounds of interest were separated solely by dispersive interactions with the reversed phase. In the example given, the corn meal was spiked with the aflatoxins. 

The second step introduces the side chain group by nucleophilic displacement of the bromide (as a resin-bound a-bromoacetamide) with an excess of primary amine. Because there is such diversity in reactivity among candidate amine submonomers, high concentrations of the amine are typically used ( l-2 M) in a polar aprotic solvent (e.g. DMSO, NMP or DMF). This 8 2 reaction is really a mono-alkylation of a primary amine, a reaction that is typically complicated by over-alkylation when amines are alkylated with halides in solution. However, since the reactive bromoacetamide is immobilized to the solid support, any over-alkyla-tion side-products would be the result of a cross-reaction with another immobilized oligomer (slow) in preference to reaction with an amine in solution at high concentration (fast). Thus, in the sub-monomer method, the solid phase serves not only to enable a rapid reaction work-up, but also to isolate reactive sites from... 

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