Chromatography HPLC column/phase

Reversed-phase high-performance liquid chromatography (HPLC) column 50 mm x 3.2-mm i.d. with Kromasil 5- um Gig packing High-performance liquid chromatograph coupled to a triple-quadrupole mass spectrometer with an atmospheric pressure chemical ionization (APCI) source Gel permeation chromatograph with a 60 mm x 25-mm i.d. column packed with Bio-Beads SX-3 (50-g)... 

A Zorbax-CN high performance liquid chromatography (HPLC) column used with hexane as mobile phase produced desirable results. Details of the HPLC procedure will be published elsewhere (5.). Three HPLC subfractions of S1-C2 were made ... 

The four common causes for high-performance liquid chromatography (HPLC) column failure include column clogging at the inlet frit (from samples/mobile phase), voids generated in the column, strongly adsorbed impurities from solvent/sample, and chemical attack of the stationary phase from the mobile phase or analytes. Procedure for removal of strongly adsorbed impurities from sample/mobile phase was discussed in Chapter 3, Section 3.9.2. 

The purity of crude peptide will be analayzed on a reverse-phase high-performance liquid chromatography (HPLC) column. The elution of the peptide is followed by absorbance recorded at 215 nm. The purification on a 10 to 20 mg scale is performed on a larger, preparative column monitored at the less sensitive wavelength of 238 nm. 

Due to high water solubility of monosaccharides, the use of the most routine high-performance liquid chromatography (HPLC) reversed-phase columns is also not suitable for their analysis. Extremely pure solvents have to be used if ultraviolet (UV) detection is applied. If a refractometer is used as the detector (RD), extremely steady chromatographic conditions are necessary. Nevertheless, HPLC is applied in the practice. The modern approach involves the use of propylamino columns (e.g.. Refs. 3 and 4). 

High-performance liquid chromatography (HPLC) Column chromatography in which the mobile phase is a liquid, often... 

One of the key issues in LC-MS involves separation of the analytes of interest from each other and from the matrix in which they are present. The introduction of the high-performance liquid chromatography (HPLC) column prior to the ionization source accomplished this task. The use of different stationary phases coupled with an appropriate selection of mobile phases and gradient conditions allowed for... 

Instmmental methods of analysis provide information about the specific composition and purity of the amines. QuaUtative information about the identity of the product (functional groups present) and quantitative analysis (amount of various components such as nitrile, amide, acid, and deterruination of unsaturation) can be obtained by infrared analysis. Gas chromatography (gc), with a Hquid phase of either Apiezon grease or Carbowax, and high performance Hquid chromatography (hplc), using siHca columns and solvent systems such as isooctane, methyl tert-huty ether, tetrahydrofuran, and methanol, are used for quantitative analysis of fatty amine mixtures. Nuclear magnetic resonance spectroscopy (nmr), both proton ( H) and carbon-13 ( C), which can be used for quaHtative and quantitative analysis, is an important method used to analyze fatty amines (8,81). 

Chromatographic Method. Progress in the development of chromatographic techniques (55), especially, in high performance Hquid chromatography, or hplc, is remarkable (56). Today, chiral separations are mainly carried out by three hplc methods chiral hplc columns, achiral hplc columns together with chiral mobile phases, and derivatization with optical reagents and separation on achiral columns. All three methods are usehil but none provides universal appHcation. 

Chemical stabiUty studies are monitored by siUca gel thin-layer chromatography (dc) or by high performance Hquid chromatography (hplc) using a reverse-phase C g coated column (24). Hplc peaks or dc spots are visualized by thek uv absorption at 245 nm the tic spots can also be detected by ceric sulfate or phosphomolybdic acid staining. 

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