High-performance liquid control

As a result of these merits thin layer chromatography finds application all over the world. The frequency of its application is documented in Figure 3. This CA search only includes those publications where TLC/HPTLC are included as key words. The actual application of the method is very much more frequent. The method is employed as a matter of course in many areas of quality control and routine monitoring of product purity. This was also true in the 1970s when the rapid development of high performance liquid chromatography (HPLG) led to a... 

Commercial grades of PVP, K-15, K-30, K-90, and K-120 and the quaternized copolymer of vinylpyrrolidone and dimthylaminoethylmethacrylate (poly-VP/ DMAEMA) made by International Specialty Products (ISP) were used in this study. PEO standard calibration kits were purchased from Polymer Laboratories Ltd. (PL), American Polymer Standards Corporation (APSC), Polymer Standards Service (PSS), and Tosoh Corporation (TSK). In addition, two narrow NIST standards, 1923 and 1924, were used to evaluate commercial PEO standards. Deionized, filtered water, and high-performance liquid chromatography grade methanol purchased from Aldrich or Fischer Scientific were used in this study. Lithium nitrate (LiN03) from Aldrich was the salt added to the mobile phases to control for polyelectrolyte effects. 

A dimer portion can be prepared exclusively from the mixed crystal by controlling the wavelength of irradiating light (>410nm) and isolated by preparative thin-layer chromatography. The high-performance liquid chro-... 

Vanheukelem, L. et al., Improved separations of phytoplankton pigment using temperature-controlled high-performance liquid chromatography. Mar. Ecol. Prog. Ser., 14, 303, 1994. 

Hayakawa, K., Hirano, M., Yoshikawa, K., Katsumata, N, and Tanaka, T., Separation of phenylthiohydantoin-amino acids by temperature-controlled reversed-phase high-performance liquid chromatography, /. Chromatogr. A, 846, 73, 1999. 

Kirkland, J. J., Techniques for high-performance liquid-liquid and ion exchange chromatography with controlled surface porosity column packings, ]. Chromatogr. Sci., 7, 361, 1969. 

High Performance Liquid Chromatographic (HPLC) Analysis. A Waters HPLC system (two Waters 501 pumps, automated gradient controller, 712 WISP, and 745 Data module) with a Shimadzu RF-535 fluorescence detector or a Waters 484 UV detector, and a 0.5 pm filter and a Rainin 30 x 4.6 mm Spheri-5 RP-18 guard column followed by a Waters 30 x 3.9 cm (10 pm particle size) p-Bondapak C18 column was used. The mobile phase consisted of a 45% aqueous solution (composed of 0.25% triethylamine, 0.9% phosphoric acid, and 0.01% sodium octyl sulfate) and 55% methanol for prazosin analysis or 40% aqueous solution and 60% methanol for naltrexone. The flow rate was 1.0 mL/min. Prazosin was measured by a fluorescence detector at 384 nm after excitation at 340 nm (8) and in vitro release samples of naltrexone were analyzed by UV detection at 254 nm. 

Miyake, K., Terada, H. (1982) Determination of partition coefficients of very hydrophobic compounds by high performance liquid chromatography on glyceryl-coated controlled-pore glass. J. Chromatogr. 240, 9-20. 

Spectrophotometric determination with 4-hexylresorcinol and a fluorometric method with m-aminophenol are the most commonly used procedures for the determination of acrolein. However, gas chromatography and high-performance liquid chromatography procedures are also used (USEPA 1980 Kissel etal. 1981 Nishikawa and Hayakawa 1986). Acrolein concentrations in rainwater between 4 and 200 pg/L can be measured rapidly (less than 80 min) without interference from related compounds the method involves acrolein bromination and analysis by gas chromatography with electron capture detection (Nishikawa and Hayakawa 1986). Kissel etal. (1981) emphasize that water samples from potential acrolein treatment systems require the use of water from that system in preparing blanks, controls, and standards and that acrolein measurements should be made at the anticipated use concentrations. 

The refractive index is another very rapid analytical method for determining purity and identity of a substance. It is uniquely useful for quality control monitoring of raw materials and finished products. Many students encounter a refractometer first as a universal detector for high-performance liquid chromatography. 

PAGE Phe Pro PSD QC Q-ToF Q-ToF-LC-MS-MS polyacrylamide gel electrophoresis phenylalanine proline post-source decay quality control quadrupole time-of-flight mass analyser quadrupole time-of-flight mass analyser in combination with (high performance) liquid chromatography and tandem mass... 

High-Performance Liquid Crystal Polyesters with Controlled Molecular Structure... 

Wynia, G. S., Windhorst, G., Post, P. C., and Maris, F. A. (1997). Development and validation of a capillary electrophoresis method within a pharmaceutical quality control environment and comparison with high-performance liquid chromatography. /. Chromatogr. A 773(1—2), 339—350. 

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