Evaporative light-scattering detection

Dsv Mean diameter of aerosol droplets a Surface tension of the mobile phase p Density of the mobile-phase viscosity p Viscosity of the mobile phase Vg Velocity of the nebulizing gas Vt Velocity of the mobile phase 

From Eq. (8.56), it can be concluded that a decrease in the flow rate of the nebulizing gas, with constant flow rate of the mobile phase, increases the average 

A plot of log / as a function of log m provides a linear response. The values of the constants k and b depend on a variety of experimental conditions such as the temperature and the nature of the mobile phase. 

---

Coquet, A., Veuthey, J.-L., and Haerdi, W., Comparison of post-column fluorescence derivatization and evaporative light-scattering detection to analyse saccharides selectively by LC, Chromatographia, 34, 651, 1992. 

Mercier, J.-P., Chaimbault, P, Elfakir, C. and Dreux, M., Inorganic ion determination by RPLC using evaporative light scattering detection, Am. Lab. News, 31(21), 1999. 

Peterson, J. A., Lorenz, L. J., Risley, D. S., and Sandmann, B. J., Amino acid analysis of peptides using HPLC with evaporative light scattering detection, /. Liq. Chromatogr. Related Technol., 22, 1009, 1999. 

Bruns, A., Waldhoff, H., and Winkle, W., Application of HPLC with evaporative light-scattering detection in fat and carbohydrate chemistry, Chro-matographia, 27, 340, 1989. 

Detection in 2DLC is the same as encountered in one-dimensional HPLC. A variety of detectors are presented in Table 5.2. The choice of detector is dependent on the molecule being detected, the problem being solved, and the separation mode used for the second dimension. If MS detection is utilized, then volatile buffers are typically used in the second-dimension separation. Ultraviolet detection is used for peptides, proteins, and any molecules that contain an appropriate chromophore. Evaporative light scattering detection has become popular for the analysis of polymers and surfactants that do not contain UV chromophores. Refractive index (RI) detection is generally used with size exclusion chromatography for the analysis of polymers. 

FIGURE 18.4 NPLC chromatogram of Triton X-100. Conditions Supelco LC-NH2 column, 15 cm x 4.6 mm and 3 pm particles linear gradient of 80/20/0 (heptane/tetrahydrofiiran/ methanol) to 0/90/10 in 40 min at a flow rate of 1 mL/min evaporative light scattering detection. 

HALS presents some analytical difficulties. Coulier et al. [18] describe a pyrolysis GC-MS method for identification and HPLC with UV and evaporative light scattering detection methods for quantification in polymer extracts. 

Fuzzati, N., Gabetta, B., Jayakar, K., Pace, R., Ramaschi, G., and Villa, F. (2000). Determination of ginsenosides in Panax ginseng roots by liquid chromatography with evaporative light-scattering detection. /. AOAC Int. 83, 820-829. 

Li, W., and Fitzloff, J. F. (2001). Determination of 24(R)-pseudoginsenoside F in North American ginseng using high performance liquid chromatography with evaporate light scattering detection. /. Pharm. Biomed. Anal. 25, 257-265. 

Risley, D.S. and Strege, M.A., Chiral separations of polar compounds by hydro-phihc interaction chromatography with evaporative light scattering detection. Anal. Chem., 72, 1736, 2000. 

Guisbert, A.L. et al.. Enantiomeric separation of an AMPA antagonist using a CHIROBIOTIC T colunm with HPLC and evaporative light-scattering detection, J. Liq. Chrom. Rel. Technol., 23, 1019, 2000. 

Recently, Caco-2 permeability screening has been optimized to accommodate the increasing demand for permeability assessment. Analytical methods like HPLC coupled with UV, evaporative light scattering detection (ELSD), or fluorescence detection were used traditionally... 

Liu CZ, Zhou HY, Zhao Y. (2007) An effective method for fast determination of artemisinin in Artemisia annua L. by high performance liquid chromatography with evaporative light scattering detection. Anal Chim Acta 581 298-302. 

As a result of advances in detection technology, newer HPLC detection techniques may be utilized. For example, evaporative light-scattering detection and refractive index detection may be used to quantify impurities with poor or no UV chromophore. Conductivity detection may also be used. In some cases, when no chromophore is present, chemical derivatization may be used to add a chromophore. Increasingly, tandem techniques such as liquid chromatography mass spectrometry (LC-MS) and GC-MS are utilized for impurity characterization. The highly selective nature of LC-MS ensures that few impurities are undetected. 

All compounds are tested as purified active ingredients. Most compounds are obtained from commercial sources, some are purified at Cerep from a formulated product, and some have been synthesized at Cerep. The purity (chromatographic purity) is measured by the aqueous solubility assay, which uses LC/MS with UV or evaporative light scattering detection to analyze the sample. More than 99% of BioPrint compoimds are >95% pure. The remaining compounds are >80% pure and are primarily compounds purified from natural extracts. 

Kibbey CE. Quantitation of combinatorial libraries of small organic molecules by normal-phase HPLC with evaporative light-scattering detection. Molecular Diversity 1, 247-258, 1996. 

Wei Y, Ding MY. Analysis of carbohydrates in drinks by high-performance liquid chromatography with a dynamically modified amino column and evaporative light scattering detection. Journal of Chromatography A 904, 113-117, 2000. 

Stith BJ, Hall J, Ayres P, Waggoner L, Moore JD, Shaw WA. Quantification of major classes of Xenopus phospholipids by high performance liquid chromatography with evaporative light scattering detection. Journal of Lipid Research A, 1448-1454, 2000. 

Megoulas NC, Koupparis MA. Twenty years of evaporative light scattering detection. Critical Reviews in Analytical Chemistry 35, 301-316, 2005. 

Capillary SFC is particularly useful for compounds that are difficult to detect using LC and too unstable for GC. Nevertheless, at present there have not been enough applications to justify an investment (74, 75). In contrast, packed-column SFC has undergone a renaissance thanks to evaporative light-scattering detection (ELSD). Packed-column SFC-ELSD is a suitable method for analyzing various compounds, with or without chromophores, and with diverse polarities, as found in drug, steroid, and ionophore complex mixtures (76-79). 

M. Anisimov, and S. L. Kaufman, Nanoparticle Detection Technology, Anal. Chem. 1999, 71, 386A C. S. Young and J. W. Dolan, Success with Evaporative Light-Scattering Detection, LCGC 2003,21, 120. 

Caboni, M.F. and Rodriguez-Estrada, M.T. 1997. High-performance liquid chromatography coupled to evaporative light scattering detection in lipid analysis Some application. Seminars in Food Analysis 2 159-169. 

---