HPLC high performance liquid stationary phase, selection

Anionic Catalysis Several bulky methacrylates afford highly isotactic, optically active polymers having a single-handed helical structure by asymmetric polymerization. The effective polymerization mechanism is mainly anionic but free-radical catalysis can also lead to helix-sense-selective polymerization. The anionic initiator systems can also be applied for the polymerization of bulky acrylates and acrylamides. The one-handed helical polymethacrylates show an excellent chiral recognition ability when used as a chiral stationary phase for high-performance liquid chromatography (HPLC) [97,98]. 

There are few methods which can measure well-defined metal fractions with sufficient sensitivity for direct use with environmental samples (approach B in Fig. 8.2). Nevertheless, this approach is necessary in the experimental determination of the distribution of compounds that are labile with respect to the time scales of the analytical method. Recent literature indicates that high-performance liquid (HPLC) and gas chromatographic (GC) based techniques may have such capabilities (Batley and Low, 1989 Chau and Wong, 1989 van Loon and Barefoot, 1992 Kitazume et al, 1993 Rottmann and Heumann, 1994 Baxter and Freeh, 1995 Szpunar-Lobinska et al, 1995 Ellis and Roberts, 1997 Vogl and Heumann, 1998). The ability to vary both the stationary and mobile phases, in conjunction with suitable detector selection (e.g. ICP-MS), provides considerable discriminatory power. HPLC is the superior method GC has the disadvantage that species normally need to be derivatised to volatile forms prior to analysis. Capillary electrophoresis also shows promise as a metal speciation tool its main advantage is the absence of potential equilibria perturbation, interactions... 

Let us first consider adsorption in relation with fullerene applications in liquid chromatography (LC) and high-performance liquid chromatography (HPLC). Saito et al. [105] first used a chemically bonded C o ilica as a stationary phase for LC, and found it to have a selectivity different from that of more traditional... 

One of the key issues in LC-MS involves separation of the analytes of interest from each other and from the matrix in which they are present. The introduction of the high-performance liquid chromatography (HPLC) column prior to the ionization source accomplished this task. The use of different stationary phases coupled with an appropriate selection of mobile phases and gradient conditions allowed for... 

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