Evaporation light scattering detector chromatography with

Thin-layer chromatography (TLC) is used both for characterization of alcohol sulfates and alcohol ether sulfates and for their analysis in mixtures. This technique, combined with the use of scanning densitometers, is a quantitative analytical method. TLC is preferred to HPLC in this case as anionic surfactants do not contain strong chromophores and the refractive index detector is of low sensitivity and not suitable for gradient elution. A recent development in HPLC detector technology, the evaporative light-scattering detector, will probably overcome these sensitivity problems. 

Trathnigg, B., Kollroser, M.J. (1997). Liquid chromatography of polyethers using universal detectors V. Quantitative aspects in the analysis of low-molecular mass poly(ethylene glycols) and their derivatives by reversed-phase HPLC with an evaporative light scattering detector. J. Chromatogr. A 768, 223-238. 

MN Vaghela, A Kilara. Quantitative analysis of phospholipids from whey protein concentrates by high performance liquid chromatography with a narrow-bore column and an evaporative light scattering detector. J Am Oil Chem Soc 72 729-733, 1995. 

Analysis of Tween 80 was performed using a Hewlett Packard 1100 series HPLC equipped with a Sedex 55 Evaporative Light Scattering Detector (ELSD). The mobile phase consisted of 80% acetonitrile and 20% water. Duplicate injections (5 pL) of each sample were evaluated by HPLC. Potassium iodide, used for the 1-D column and 2-D box tracer studies, was analyzed with a continuous flow Isco V4 variable UV wavelength absorbance detector equipped with an EZChrom Chromatography data acquisition system. 

The evaporative light-scattering detector (ELSD) was originally developed for use with high-performance liquid chromatography (HPLC) to detect nonvolatile compounds by mass rather than ultraviolet (UV) absorbance detection [1], The response is dependent on the light scattered from particles of the solute remaining after the mobile phase has evaporated and is proportional to the total amount of the solute. Because no chromophore is necessary, a response can be measured for any solute less volatile than the mobile phase. 

Wang, T. and Hammond, E.G. (1999) Fractionation of soybean phospholipids by high-performance liquid chromatography with an evaporative light scattering detector. J. Am. Oil Chem. Soc., 76, 1313-1321. 

Detection methods HPLC-DAD, HPLC with diode-array detection. HPLC-(ESI-MS), HPLC with electrospray ionization mass spectrometry. RP-HPLC, revcrsed-phase HPLC. UPLC/Q-TOFMS, UPLC with quadrupole-time of flight mass spectrometry. HPLC-APCI-MS, HPLC with atmospheric pressure chemical ionization mass spectrometry. CE-IT-MS, capillary elecliophoresis-ion-1r mass spectrometry. LC-ESI-ITMS, liquid chromatography-electrospray ionization ion trap mass spectrometry. LC-ELSD, LC with evaporative light scattering detector. DNBZ-Cl, 3,5-dinitrobenzoyl chloride. 

J. Li, M. Chen and Y. Zhu, Separation and determination of carbohydrates in drinks by ion chromatography with a self-generating suppressor and an evaporative light-scattering detector, /. Chromatogr. A, 1155, 50-56, 2007. 

Because purity determined by liquid chromatography (LC) or LC-mass spectrometry (LC-MS) with ultraviolet (UV) or evaporative light scattering detector (ELSD) detection represents only relative purity, the presence of impurities such as inorganics, materials with poor chromophores and/or good evaporative properties, and materials that tend to be retained by a guard column cannot be detected. Therefore, we measure the absolute purity of six representative compounds in each library at both optimization and production stages. 

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