Liquid chromatography—See

If maltenes are subjected to liquid chromatography (see 2.1.2.4) the components eluted by the more polar solvents are called resins. Their composition, once again, depends on the procedure used. 

Most of the work on chiral recognition has been carried out with amino-acid ester salts. The limited number of available data of similar experiments with amino-acid salts point to an increased enantiomeric differentiation (Table 69 Peacock and Cram, 1976). The reason might be the higher -acidity of the carboxyl group (vide ir fra). In solid-liquid chromatography (see Table 68) the difference between amino-acid salts and amino-acid ester salts is not consistent and not always in favour of the amino-acid salts. However, it should be... 

Figure 4. Correlation of seed germination inhibition (x-x) with GC peak size of compound RT = 29.5 min (o-o) of fractions 68-73 of the liquid chromatography (see Figure 3). (Reproduced with permission from reference 6. Copyright 1982 Verlag der Zeitschrift fur Naturforschung.)...

Gas Chromatography and Gas Liquid Chromatography. See Vol 3 of Encycl, p C293 R. under CHROMATOGRAPHY. 

Pulse polarographic studies have been described using a microcell of 0.5 mL capacity, which analyzed two 1,4-benzodiazepines, with the lowest detection limit reported to date being 10-20 ng/mL of blood [199]. Detailed construction of the cell and electrode assembly was also described (shown in Fig. 26.16). Further miniaturization of this type of three-electrode cell is not practical hence further increases in sensitivity will have to rely on electrochemical detector flow cells of microliter capacity such as those used in conjunction with liquid chromatography (see Chap. 27). 

The procedure involves precolumn oxidation of formate with formate dehydrogenase which is accompanied by a corresponding reduction of p-nicotinamideadenine dinucleotide (P(NAD)+) to reduced P-nicotinamide dinucleotide (ie P NADH). The latter is quantified by high performance liquid chromatography. See also Table 4.1. 

If the stationary phase is asolid surface, then the term adsorption isotherm is more commonly used. However, in some kinds of chromatography (e.g. reversed phase liquid chromatography, see section 3.2) the phase ratio may vary with variations in the mobile phase composition. 

Related substances. Carry out the method for liquid chromatography (see Appendix III D of the BP), using the following solutions ... 

This work uncovered the fact that a substitution of the amino acid alanine for valine at position 126 in the /3-chain of hemoglobin occurred in a hemato-logically normal adult of Lebanese extraction. The variation /3-globin was initially observed and subsequently purified by reverse-phase liquid chromatography (see Fig. 2-5). Also LC was used to isolate the variant tryptic peptide of /3-T13 that had alanine replacing the valine at amino-acid residue position 126. This is shown in Figure 2-6. (Peptide mapping is discussed later in this chapter.)... 

The reaction solution is often dark-colored at the beginning but lightens as reflux continues. The reflux time may be varied with the amount of ketone to be reduced. The completeness of the reaction may be followed by removing small aliquots, working up these samples as described in the text, and analyzing the product mixture by gas-liquid chromatography (see Note 6). 

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