Chromatographic packings

Chromatographic Packings Prepared by Physical Adsorption of Polymers... 

Chromatographic Packings Prepared by Covalently Bound Polymers and Oligomers... 

Chromatographic Packings Prepared by Graft Polymerization of Monomers... 

Commercial silica gels are available with a wide range of properties. The characteristics of some common chromatographic packings are summarized in Table 4.3 (36). These data are taken mainly from the survey of Sander and Wise and are based on experimental determinations from a single batch of material. The... 

Specifications for chromatographic packings often describe maximum loading in terms of the maximum capacity of a unit quantity of the packing to bind some analyte, often a well characterized protein such as bovine serum albumin. The static loading capacity35 is very different from functional capacity,2 which is the maximum amount of a particular feedstock that can be loaded and still achieve acceptable purification and recovery. Functional capacity is determined empirically for each type of load and associated set... 

Bogar, R.G., Thomas, J.C., and Callis, J.B., Lateral diffusion of solutes bound to the alkyl surface of Cl8 reversed phase liquid chromatographic packings. Anal. Chem., 56, 1080, 1984. 

FIGURE 1.9 Schematic illustration of the measurement ranges of MIP, BET, and ISEC together with the pore range, being relevant for chromatographic packings. 

In addition to the solubility parameter model to treat SEC adsorption effects, an approach based on Flory-Huggins interaction parameters has also been proposed (24-27). For an excellent review of both mechanisms, see reference 28.- A general treatment of polymer adsorption onto chromatographic packings can be found in Belenkii and Vilenchik s recent book (29). 

The sample extract may be analyzed by GC or GC/MS. A 2- to 5-pL aliquot of the extract is injected into a GC and the phthalates are detected by an electron capture detector, a flame ionization detector (FID), or a photoionization detector. Some of the chromatographic packed or capillary columns that may be used for the phthalate analysis are hsted below ... 

A vast range of materials have been bonded to silica such as phenyl, cyano, nitro, amino, and diol functionalities. The variety of silica-based sorbents are listed in the United States Pharmacopeia (USP) [23] where it is noted that of the 33 column packings, 19 are silica based. The synthesis and characteristics of over 80 nonconventional bonded silicas have been reviewed [24]. In spite of the number of chromatographic packings, 50% of the chromatographers develop methods using a C18 sorbent [1]. Sorbents... 

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