Partition chromatograph

There is no other facet where thin-layer chromatography reveals its paper-chromatographic ancestry more clearly than in the question of development chambers (Fig. 56). Scaled-down paper-chromatographic chambers are still used for development to this day. From the beginning these possessed a vapor space, to allow an equilibration of the whole system for partition-chromatographic separations. The organic mobile phase was placed in the upper trough after the internal space of the chamber and, hence, the paper had been saturated, via the vapor phase, with the hydrophilic lower phase on the base of the chamber. 

R. Consden, A. H. Gordon and A. J. P. Martin, Qualitative analysis of proteins partition chromatographic method using paper , 7. Biochem. 38 224-232 (1944). 

TNMe on alkaline hydrolysis. In an ion exclusion-partition chromatographic method for the sepn of acids, TNMe emerged from the column betw citric and itaconic acids (Ref 36) Impact Sensitivity. On the BRL machine (1kg wt), using a noisemeter to detect explns, the 50% expin height was found to be 218cm. A 50/50 mixt with kerosene had a 50% expln height of 130cm (Ref 21)... 

In partition chromatographic systems, the selectivity and degree of retention are mainly determined by the compositions of the liquid stationary and mobile phases and by the phase ratio of these two liquids. 

Aluminum oxides, similar to silica gels, are available as bulk materials and as precoated plates, to be used not only for straight phase adsorption chromatography, but also for partition PLC (see Table 3.3 and Table 3.4). In particular, the aluminum oxide type 150 (i.e., mean pore diameter 150 A [15 tun]) is suitable for partition chromatographic purposes. 

Partition Chromatographic Column. The column was constructed of standard-wall borosilicate glass pipe by the Scientific Glass Apparatus Company. It is 83 cm. 

El Tayar, N. Tsai, R.-S. Vallat, P. Altomare, C. Testa, B., Measurement of partition coefficients by various centrifugal partition chromatographic techniques. A comparative evaluation, J. Chromatogr. 556, 181-194 (1991). 

Consden, R., Gordon, A.H., Martin, AJ.P. (1944). Qualitative analysis of proteins a partition chromatographic method using paper. Biochemical J 38, 224—232. 

The USP recommends a column partition chromatographic method for the assay of tablets and ampoules. The analyte is separated using a chromatographic separation, and the isoxsuprine concentration determined by spectrophotometiy. 

Name and acronym Centrifugal partition chromatograph (CPC) High-speed countercurrent chromatograph (HSGGG)... 

Martin and Porter (19) described a partition chromatographic procedure and first demonstrated the presence of at least one minor active component in the crystalline enzyme preparation. King and Craig (20) found a solvent system permitting effective countercurrent distribution of ribonuclease, ethanol water ammonium sulfate in the ratios 25.9 -57.6 16.5. The principal component of the Kunitz preparation behaved as an almost ideal solute with a partition ratio of 0.8. Albertsson has provided a liquid polymer countercurrent system based on dextrari and methyl cellulose (21). 

El Tayar, N., R.-S. Tsai, P. Vallat, C. Altomare, and B. Testa. 1991. Measurement of Partition Coefficients by Various Centrifuge Partition Chromatographic Techniques A Comparative Evaluation. /. Chromatog. 556 181-194. 

Enzymatic production of L-amino acids 73 Centrifugal partition chromatographic reactor... 

Paper partition chromatographic methods have been widely applied to the analysis of tetracyclines (128, 129). Pharmaceutical aqueous suspensions for oral use are acidified with HC1 and diluted with methanol. Crystalline formulations are dissolved only in methanol. A paper chromatographic method for TC determination in pharmaceutical preparations is based on the complexation of the antibiotic with a mixture of urea and disodium edetate on paper at pH 7.4. Urea helped in the separation of degradation products and led to the formation of well defined spots (130). Samples from fermentations must be acidified with oxalic acid to liberate TC from the mycelium. TC in filtrates may be precipitated in saturated solution of sodium tetraphenyl borate, precipitate dissolved in ethyl or butyl acetate and applied for paper chromatography. Various solvent systems and hRp values for paper chromatography are given in Table 4. 

Solute retention in reversed-phase HPLC is dependent on the different distribution coefficients established between a polar mobile and a nonpolar stationary phase by the peptidic components of a mixture. Although there are many similarities between reversed-phase HPLC separations of peptides and the classical liquid-liquid partition chromatographic methods, it is debatable whether the sorption process in reversed-phase HPLC arises due to partition or adsorption events, i.e., whether the nonpolar stationary phase functions as a bulk liquid or as an adsorptive monolayer. These aspects and the theoretical models for reversed-phase HPLC are discussed in a subsequent section. 

On the other hand, the partition chromatographic systems are not identical with the... 

Countercurrent chromatography (CCC), as a support-free liquid-liquid partition chromatographic separation tech-... 

Menet et al. [6] have compared performances of CCC and preparative HPLC owing to a separation of two antibiotics X and Y. The CCC apparatus used was a centrifugal partition chromatograph (CPC, Sanki LLN) of 250 mL internal volume. For this purpose, classical parameters of preparative-scale chromatography were calculated experimental duration, including the sample preparation and the separation time, solvent consumption, including the volume of the mobile phase, the stationary phase and the injection solvent, and purity of the purest fraction in Y. The parameter purity in Y was chosen because Y is the solute most difficult to purify because of its physical properties (particularly hydrophobicity) which are close to those of the main impurities. The hourly yield (g/h) is defined as the ratio of the recovered quantity to the experimental duration. The volumic yield (g/L) is defined as the ratio of the recovered quantity to the solvent consumption. Table 1 summarizes the results of... 

Y. Surakitbanharn, H. Freiser, and S. Mnralidharan, Centrifugal partition chromatographic separations of platinum group metals by complexation and ion pair formation, Chem. 68 3934 (1996). 

K. Inaba, H. Freiser, and S. Muralidharan, Effect of kinetic factors on the efficiencies of centrifngal partition chromatographic separations of tervalent lanthanides with bis(2,4,4,-trimethylpentyl)phosphinic acid as extractant, Solvent Extract Res. Dev. Japan 1 13 (1994). G. Ma, H. Freiser, and S. Mnralidharan, Centrifugal partition chromatographic separation of tervalent lanthanides using acylpyrazolone extractants, A aZ. Chem. 69 2835 (1997). 

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