Chromatographic retention index

Hall GL, Whitehead WE, Mourer CR, et al. 1986. A new gas chromatographic retention index for pesticides and related compounds. J High Resolut Chromatogr Commun 9 266-271. 

Musumarra et al. [44] also identified miconazole and other drugs by principal components analysis of standardized thin-layer chromatographic data in four eluent systems and of retention indexes on SE 30. The principal component analysis of standardized R values in four eluents systems ethylacetate-methanol-30% ammonia (85 10 15), cyclohexane-toluene-diethylamine (65 25 10), ethylacetate-chloroform (50 50), and acetone with plates dipped in potassium hydroxide solution, and of gas chromatographic retention indexes in SE 30 for 277 compounds provided a two principal components model that explains 82% of the total variance. The scores plot allowed identification of unknowns or restriction of the range of inquiry to very few candidates. Comparison of these candidates with those selected from another principal components model derived from thin-layer chromatographic data only allowed identification of the drug in all the examined cases. 

Today, GC-MS (see Section 4.1.1) is a golden standard for detection and quantification of drugs and poisons volatile under GC conditions, whereas nonvolatile compounds require LC-MS (see Section 4.1.2). The GC-MS technique is much more popular for identification purposes than LC-MS, because of the easy availability of the reference mass spectra for many xenobiotics and their derivatives, either in printed or computer form. The most popular libraries are the NIST library, which contains the mass spectra of 130,000 compounds, the Wiley Registry of Mass Spectral Data, which contains 390,000 reference spectra, and the Pfleger-Maurer-Weber library, with 6,300 mass spectra and other data, such as chromatographic retention indexes. 

This index was applied to correlations with gas chromatographic retention index, boiling points, standard enthalpies of formation in gas phase, heats of solution, refractive indices, theoretically calculated total surface area of alkanes. 

Some authors use the notation Rm or Rm instead of Rr>. This notation, however, can be confused with the use of Rm, the chromatographic retention index. Here RD is used to indicate molar refraction, where the subscript D refers to the sodium D line used for measurement. 

Estimation of pv for PCBs Burkhard et al. [8] compared the predictive capability of 11 different methods to estimate pvap for PCBs at 25°C. The comparison includes solely structure-based methods and methods that require the input of Tm, Th, and the entropy of fusion, ASfUS, or a gas-liquid chromatographic retention index. 

Wang, Y.H., Wong, P.K. (2002) Mathematical relationships between vapor pressure, water solubility, Henry s law constant, n-octanol/water partition coefficient and gas chromatographic retention index of polychlorinated-dibenzo-dioxins. Water Res. 36, 350-355. 

J. K. Baker, Estimation of high-pressure liquid chromatographic retention indexes, Anal. Chem., 57 1693 (1979). 

Hale MD, Hileman FD, Mazer T, Shell TL, Noble RW, Brooks JJ (1985), Anal. Chem. 57 640-648.. .Mathematical modeling of temperature programmed capillary gas chromatographic retention indexes for polychlorinated dibenzofurans"... 

Mass spectrum and chromatographic retention index match those of an authentic reference compound. 

Buydens, L., Massart, D.L. and Geerlings, P. (1983b). Prediction of Gas Chromatographic Retention Indexes with Topological, Physicochemical, and Quantum Chemical Parameters. Anal. Chem.,55,738-744. 

Kier, L.B. and Hall, L.H. (1979). Molecular Connectivity Analyses of Structure Influencing Chromatographic Retention Indexes. J.Pharm.ScL, 68,120-122. 

Klappa, S.A. and Long, G.R. (1992). Computer Assisted Determination of the Biological Activity of Polychlorinated Biphenyls Using Gas Chromatographic Retention Indexes as Molecular Descriptors. Anal.Chim.Acta, 259,89-93. 

Robbat Jr., A., Corso, N.P., Doherty, P.J. and Marshall, D. (1986a). Multivariate Relationships Between Gas Chromatographic Retention Index and Molecular Connectivity of Mononitrated Polycyclic Aromatic Hydrocarbons. Anal.Chem., 58,2072-2077. 

Rohrbaugh, R.H. and Jurs, PC. (1985). Prediction of Gas Chromatographic Retention Indexes of Selected Olefins. Anal.Chem.,57,2770-2773. 

Rohrbaugh, R.H. and Jurs, P.C. (1986) Prediction of gas chromatographic retention indexes of polycyclic aromatic compounds and nitrated polycyclic aromatic compounds. Anal. Chem.,... 

R. H. Rohrbaugh and P. C.. lurs. Anal. Chem., 59, 1048 (1987). Molecular Shape and the Prediction of High-Performance Liquid Chromatographic Retention Indexes of Polycyclic Aromatic Hydrocarbons. See also, P. C. Jurs, in Reviews in Computational Chemistry, K. B. l.ip-kowitz and D. B. Boyd, Eds., VCH Publishers, New York, 1990, pp. 169-212. Chemomctrics and. Multivariate Analysis in Analytical Chemistry. 

We would like to critically examine the interpretation of the regression equation (2) that it supports a notion that the Chromatographic retention index for benzenoids is shape dependent. As one can see from equation (1), most of the correlation between the structure and the Chromatographic retention index as the property is described by the connectivity index that is bond additive and size dependent. The conclusion therefore ought to be that the Chromatographic retention values are mostly bond additive and size dependent. Because of this pronounced bond-additivity, clearly we can understand why indices that are global are inferior in this particular application. 

We have to conclude that the Chromatographic retention index for planar benzenoids is inherently not a shape-dependent property, i.e., it is not a property that will be determined solely by the atoms on the molecular periphery. One may wonder Why... 

Millership and Woolfson have investigated the relation between chi indices and the chromatographic retention index (RI). They reported a QSAR based on two chi indices (equation 25) . 

Heldt, U. Koser, H.J.K. Different bases for the gas chromatographic retention index system. J. Chromatogr. 1980, 192, 107-116. 

Gas Chromatographic Retention Indexes of Twenty Metabolically Important Acylglycines as Trimethyls ilyl Derivatives... 

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