Novel interfaces

A novel interface to connect a ce system with an inductively coupled plasma mass spectrometric (icpms) detector has been developed (88). The interface was built using a direct injection nebulizer (din) system. The ce/din/icpms system was evaluated using samples containing selected alkah, alkaline earths, and heavy-metal ions, as well as selenium (Se(IV) and Se(VI)), and various inorganic and organic arsenic species. The preliminary results show that the system can be used to determine metal species at ppt to ppb level. 

Q. Zhan, A. Gusev, and D. M. Hercules, A novel interface for on-line coupling of liquid capillary chromatography with matrix-assisted laser desorption/ionization detection, Rapid Commun. Mass Spectrom., 13 (1999) 2278-2283. 

Zhu G, Wang P (2005) Novel interface-binding chloroperoxidase for interfacial epoxidation of styrene. J Biotechnol 117 195-202... 

Plasma ultrafiltrates were diltued 1 50 and analyzed by RP-HPLC (column packed with PLRP-S, Polymer Laboratories) with solvent gradient elution (acetonitrile-water from 15 85 to 90 10, 30 min), coupled to ICP-MS through a novel interface, allowing efficient elimination of acetonitrile... 

Hitomi, K., Oyama, T., Han, S., Arvai, A.S., and Getzoff, E.D. (2005). Tetrameric architecture of the circadian clock protein KaiB a novel interface for intermolecular interactions and its impact on the circadian rhythm. J. Biol. Chem. 280, 19125-19137. 

Amorphous and semi-crystalline polypropylene samples were pyrolyzed in He from 388°-438°C and in air from 240°-289°C. A novel interfaced pyrolysis gas chromatographic peak identification system was used to analyze the products on-the-fly the chemical structures of the products were determined also by mass spectrometry. Pyrolysis of polypropylene in He has activation energies of 5-1-56 kcal mol 1 and a first-order rate constant of JO 3 sec 1 at 414°C. The olefinic products observed can be rationalized by a mechanism involving intramolecular chain transfer processes of primary and secondary alkyl radicals, the latter being of greater importance. Oxidative pyrolysis of polypropylene has an activation energy of about 16 kcal mol 1 the first-order rate constant is about 5 X JO 3 sec 1 at 264°C. The main products aside from C02, H20, acetaldehyde, and hydrocarbons are ketones. A simple mechanistic scheme has been proposed involving C-C scissions of tertiary alkoxy radical accompanied by H transfer, which can account for most of the observed products. Similar processes for secondary alkoxy radicals seem to lead mainly to formaldehyde. Differences in pyrolysis product distributions reported here and by other workers may be attributed to the rapid removal of the products by the carrier gas in our experiments. 

A novel interfaced pyrolysis gas chromatographic peak identification system has been used to study the pyrolysis and oxidative pyrolysis of... 

The rapid LC methods employed for array analysis produce typical peak widths at half-height of less than 2 s. It was immediately apparent that the scan rates achievable on a radiofrequency (RF) quadrupole mass spectrometer would not be sufficient to generate high-quality mass spectra that could be used to confirm the presence of a desired chemical entity. Alternatively, commercial orthogonal time-of-flight (TOF) mass spectrometers can acquire full scan profile data at rates approaching 10 Hz so that rapid switching between up to four streams becomes feasible. Therefore this approach was followed in our development of the novel interface based on the Micromass LCT instrument. 

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