Chromatographic retention behavior

For the complex mixtures to which GC/MS and LC/MS are most commonly applied, the unknown components more often are only known to have specific chromatographic-retention behavior, or to belong to very broad classes of compounds, such as basic or non-polar. 

Mossner, S.G., Lopez de Alda, M.J., Sander, L.C., Lee, M.L. and Wise, S.A. (1999). Gas Chromatographic Retention Behavior of Polycyclic Aromatic Sulfur Heterocyclic Compounds, (diben-zothiophene, naphtho[b]thiophenes, benzo[b]naphthothiophenes and alkyl-substituted derivatives) on Stationary Phases of Different Selectivity. J.Chromat., 841,207-228. 

Saito, Y., Nojiri, M., Shimizu, Y., and Jinno, K., Liquid chromatographic retention behavior of polycycUc aromatic hydrocarbons on newly-synthesized chitosan stationary phases crosslinked with long aUphatic chains, J. Liq. Chromatogr. Relat. Technol, 25, 2767-2779, 2002. 

C. A. Chang, H. Abdel-Aziz, N. Melchor, Q. Wu and K. H. Panned, Liquid Chromatographic Retention Behavior of Organometallic Compounds and Ligands with Amine-, Octadecyl-Silica- and P-Cyclodextrin Bonded-Phase Columns, J. Chromatogr., 347(1985)51. 

M. Paleologou, S. Li and W.C. Purdy, Liquid Chromatographic Retention Behavior and Separation of Chlorophenols on a 3-Cyclodextrin Bonded Phase Column. Part m. Diaromatic Chlorophenols, Can. J. Chem., 68(1990)1208. 

Figure 11.12 Chromatographic retention behavior of adenosine and deoxyade-nosine on the click boronate affinity hybrid monolith (1) 1 mg mL" 2-deoxyadenosine (2) 1 mg mL" adenosine (3) a mixture of 1 mg mL" adenosine and 1 mg mL" 2-deoxyadenosine. The experimental conditions were as follows phosphate buffer (pH 7.5,0.1 M) containing 0.3 M NaCl, switched to 0.2 M acetic acid at 13 min. (Reproduced from ref. 54 with permission. Copyright 2013, Springer.)...

Hill, R.E., Retention behavior of a bonded reversed phase in high performance liquid chromatographic assay of serum theophylline, J. Chromatogr., 135,419,1977. 

Aleksic et al. [47] estimated the hydrophobicity of miconazole and other antimycotic drugs by a planar chromatographic method. The retention behavior of the drugs have been determined by TLC by using the binary mobile phases acetone-n-hexane, methanol toluene, and methyl ethyl ketone toluene containing different amounts of organic modifier. Hydrophobicity was established from the linear relationships between the solute RM values and the concentration of organic modifier. Calculated values of RMO and CO were considered for application in quantitative structure activity relationship studies of the antimycotics. 

With just a few exceptions, there is a dearth of published information providing systematic studies of retention volumes as a function of composition of the eluent over the whole composition range of binary solvents. To rectify this situation, a general equation for HPLC binary solvent retention behavior has been proposed [59] that should help generate a chromatographic retention model to fit Eq. (15.20) ... 

Kazuhiro, K., Tanaka, N., Iwaguchi, K., Onishi, S., Jinno, K., Eksteen, R., Hosoya, K. and Araki, M., Chromatographic Characterization of Silica Cjg Packing Materials. Correlation between a Preparation Method and Retention Behavior of Stationary Phase./. Chromatogr. Sci., 27 721—728, 1989. 

Uf course, the enhancement of chromatographic selectivity by secondary chemical equilibria is neither new nor confined to reversed-phase systems. Most widespread probably has been the exploitation of protonic equilibria by appropriately ati usting the pH of the eluent so that the degree of ionization of the eluite is altered. Generally the ionized and neutral forms of an eluite are retained differently (2( 7. 208). Formation of metal complexes of certain eluites has also been utilized for modulating retention behavior for higher selectivity. 

Several different physicochemical models have been proposed to predict and explain the retention behavior in liquid-solid chromatography. The models can be divided into two groups depending on the assumptions made concerning the fundamental mechanism of the chromatographic process. The two assumptions are as follows ... 

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