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HPLC column properties

To date, the shortcomings in the theoretical [22] and functional description of HPLC column properties make all these theories insufficient for practical application to HPLC method design and selection. [Pg.506]

The first observation of the enantioselective properties of an albumin was made in 1958 (28) when it was discovered that the affinity for L-tryptophan exceeded that of the D-enantiomer by a factor of approximately 100. This led to more studies in 1973 of the separation of DL-tryptophan [54-12-6] C22H22N2O2, on BSA immobilized to Sepharose (29). After extensive investigation of the chromatographic behavior of numerous racemic compounds under different mobile-phase conditions, a BSA-SILICA hplc column (Resolvosil-R-BSA, Macherey-Nagel GmvH, Duren, Germany) was... [Pg.99]

In this work the state-of-the-art and perspectives of column characterization and compai ison have been presented and discussed. All information about physico-chemical properties of RP HPLC Cl8 and C8 columns as porosity, average surface area, free silanol concentration, binding ligand density and others, were summarized. The points of views about column classifications, its advantages and disadvantages were discussed. It was shown that Cl8 and C8 HPLC column classification processes do not allow selecting the column with the same or preai range selectivity. [Pg.131]

M., La Rotonda, M. L, Testa, B. Structural properties governing retention mechanisms on immobilized artificial membrane (lAM) HPLC columns. Helv. Chim. Acta 2002, 85, 519-532. [Pg.433]

In NPLC, which refers to the use of adsorption, i.e. liquid-solid chromatography (LSC), the surface of microparticulate silica (or other adsorbent) constitutes the most commonly used polar stationary phase normal bonded-phase chromatography (N-BPC) is typified by nitrile- or amino-bonded stationary phases. Silica columns with a broad range of properties are commercially available (with standard particle sizes of 3, 5 and 10 im, and pore sizes of about 6-15nm). A typical HPLC column is packed with a stationary phase of a pore size of 10 nm and contains a surface area of between 100 and 150m2 mL-1 of mobile phase volume. [Pg.236]

Small bore or microbore is a term used for hplc columns that have diameters less than about 2 mm. Columns of this type were first used as long ago as 1967, but at that time the influence of extra-column dispersion was not appreciated, so that the columns were not used in chromatographs of appropriate design. In 1977 there was a renewal of interest in the properties of small bore columns, but it is only in the last few years that systems have become commercially available that allow the potential of small bore columns to be realised. Several manufacturers are now marketing a range of small bore columns, and a number of recent hplc instruments are claimed to be compatible with them. [Pg.41]

Since its creation around 1973, modern high-pressure liquid chromatography (HPLC) has played a dominant role in the analysis of pharmaceuticals. It is used in many different applications for example, in content uniformity assays and stability-indicating methods, for the purity profiles of drug substances, or in the analysis of drug metabolism in animals and humans. The heart of all of these assays is the HPLC column. In this chapter, we will describe the fundamental properties of HPLC columns as well as how these properties influence column performance and separation characteristics in pharmaceutical assays. [Pg.78]

Breneman, C. M. and Rhem, M. (1997) QSPR Analysis of HPLC column capacity factors for a set of high-energy materials using electronic van der Waals surface property descriptors computed by transferable atom equivalent method. J. Comput. Chem. 18, 182-197. [Pg.424]

Monolithic stationary phases have to be regarded as the first substantial further development of HPLC columns, as they present a single particle separation medium, made up of porous polymer. As a consequence of their macroporous structure, they feature a number of advantages over microparticulate columns in terms of separation characteristics, hydrodynamic properties, as well as their fabrication ... [Pg.16]

Consideration of log P can also be useful to assess extractability by solid-phase extraction (SPE) using reversed-phase (RP) material as well as retention properties on HPLC columns of such material [28],... [Pg.294]

The silica-based TSK-2000 size exclusion HPLC column has excellent separation properties for proteins in MW range 2000-20,000, when 0.1% aqueous TFA is used as eluent (3,10). We have not seen this property when solvents at neutral pH were used or with other size-exclusion HPLC columns (resin-based as well as zirkoniumoxide-based). The use of 0.1% aqueous TFA solution also dramatically increases the recovery of chemokines. Nevertheless, the TSK-2000 column should be used only when other methods of purification cannot be applied. [Pg.8]

Levels of drug and/or its metabolite have to be determined in plasma samples collected during the course of a toxicity study in order to evaluate the toxicokinetics of that compound. The UV absorption properties of the compound are used to determine the compound of interest. Since many of the endogenous compounds also show absorption in that wavelength range, a tailored sample work-up has to provide additional selectivity for the compound of interest. In addition, the plasma proteins have to be removed by the work-up in order to avoid blocking of the HPLC columns. Three principles are generally applied to remove the proteins from the sample Protein precipitation, liquid/liquid extraction and liquid/solid extraction. [Pg.601]

In the previous sections of this chapter we mainly discussed the properties of HPLC packing materials (adsorbents) and the influence of their physical and chemical properties on HPLC retention. In the following sections we will concentrate primarily on the properties of HPLC column itself. [Pg.118]

In Chapters 2, 3, and 4, all aspects of the analyte retention on the HPLC column are discussed. There are many mathematical functions describing retention dependencies versus various parameters (organic composition, temperature, pH, etc.). Most of these dependencies rely on empirical coefficients. Analyte retention is a function of many factors analyte interactions with the stationary and mobile phases analyte structure and chemical properties struc-... [Pg.504]

R. M. Smith, P. V. Snbba Rao, S. Dnbe, and H. Shah, Problems of the interlaboratory transferabihty of the measnrement of the properties of a reversed-phase HPLC column, Chromatogr. Suppl. 57 (2003), S27-S37. [Pg.762]


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See also in sourсe #XX -- [ Pg.77 ]




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HPLC column

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