Chromatography column performance

S Maeno, PA Rodriguez. Simple and versatile injection system for capillary gas chromatography columns performance evaluation of a system including mass spectrometry and light-pipe Fourier-transform infrared detection. J Chromatogr 731 201-215, 1996. 

Liquid chromatography was performed on symmetry 5 p.m (100 X 4.6 mm i.d) column at 40°C. The mobile phase consisted of acetronitrile 0.043 M H PO (36 63, v/v) adjusted to pH 6.7 with 5 M NaOH and pumped at a flow rate of 1.2 ml/min. Detection of clarithromycin and azithromycin as an internal standard (I.S) was monitored on an electrochemical detector operated at a potential of 0.85 Volt. Each analysis required no longer than 14 min. Quantitation over the range of 0.05 - 5.0 p.g/ml was made by correlating peak area ratio of the dmg to that of the I.S versus concentration. A linear relationship was verified as indicated by a correlation coefficient, r, better than 0.999. 

Ion-exchange chromatography involves an electrostatic process which depends on the relative affinities of various types of ions for an immobilised assembly of ions of opposite charge. The stationary phase is an aqueous buffer with a fixed pH or an aqueous mixture of buffers in which the pH is continuously increased or decreased as the separation may require. This form of liquid chromatography can also be performed at high inlet pressures of liquid with increased column performances. 

Flash column chromatography was performed using silica gel (6 cm diameter x 35 cm height), eluting with 19/1 hexane/diethyl ether. 

Flash column chromatography was performed using silica gel (10 cm diameter 27 cm height), eluting with 4/1 toluene/hexane. A small amount of aryl chloride that remained unreacted after 72 hr was recovered mixed with a small quantity (<5%) of the desired product. 

Reversed-phase Cig chromatography column. Keystone Scientific Betasil, 100 x 2.0-mm i.d., 5-pm particle size, 100 A, Part No. 105-701-2-CPF TSQ 7000 LC/MS/MS system with electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) interface and gradient high-performance liquid chromatography (HPLC) unit, or equivalent Vacuum manifold for use with SPE cartridges (Varian Vac Elut 10 or equivalent)... 

Performance Characterization of Liquid Chromatography Columns Using Reduced Parameters... 

Dapremont, O., Cox, G.B., Martin, M., Hilaireau, P., and Colin, H., Effect of radial gradient of temperature on the performance of large-diameter high-performance liquid chromatography columns I. Analytical conditions,. Chromatogr. A, 796, 81, 1998. 

Pfannkoch, E., Lu, K. C., Regnier, F. E., and Barth, H. G., Characterization of some commercial high-performance size-exclusion chromatography columns for water-soluble polymers, /. Chromatogr. Sci., 18, 430, 1980. 

Gel permeation chromatography was performed in tetrahydrofuran using a Waters pump system and a Model 410 differential refractive index detector for the eluant. Five Ultrastyragel columns with nominal porosities ranging from 500 to 105 angstroms were used for all the samples and the polystyrene standards. 

R. Ricker, L. Sandoval, B. Permar, and B. Boyes, Improved reversed-phase high performance liquid chromatography columns for biopharmaceutical analysis, J. Pharmaceut. Biomed. Anal., 14, 93 (1995). 

Lamprecht, G., Kraushofer, T., Stoschitzky, K., Lindner, W. (2000). Enantioselective analysis of (R)- and (S)-atenolol I urine samples by a high-performance liquid chromatography column-switching setup. J. Chromatogr. B 740, 219-226. 

Donovan, S.F., Pescatore, M.C. (2002) Method for measuring the logarithm of the octanol-water partition coefficient by using short octadecyl-poly(vinyl alcohol) high-performance liquid chromatography columns. J. Chromatogr. A, 952, 47-61. 

Analytical size exclusion chromatography was performed on an Akta Purifier (Pharmacia) using a 24-ml Superose 6 HR 10/30 column (Pharmacia). 250-pl samples in AP-buffer (20mM Tris buffer, pH 8.0, 100 mM NaCl), with or without 0.1 % P-DM, were injected onto the column equilibrated with the same buffer and eluted at a flow rate of 0.3 ml min 1. Elution profiles were recorded at 220, 280 and 674 nm. 

Analytical size exclusion chromatography was performed on a Waters HPLC system using a Biosil SEC-400 column (Biorad) acc. to [Kuhl et at. 2000] in order to examine the oligomerization status ofPSl and PS2. 

Flash column chromatography was performed using Merck 60-silica gel (40-63 pm) and solvents were obtained commercially and used as received. 

A bottle of fizzy drink going flat is a fairly trivial example of partition, but the principle is vital to processes such as reactions in two-phase media or the operation of a high-performance liquid chromatography column. 

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