Liquid chromatography distribution studies

The wide distribution of this insecticide in other cruciferous crops was investigated later, and the stability and occurrence of this compound were studied. Two cabbage varieties, cauliflower, brussels sprouts, broccoli, kale, mustard, and kohlrabi contained 2-phenylethyl isothiocyanate in various amounts as evidenced by gas-liquid chromatography and bioassay (houseflies and vinegar flies) (Table VII). Insecticidal activities were encountered only with root tissues. Compounds of insecticidal activity, not attributable to 2-phenylethyl isothiocyanate, were found in the edible parts of radish and leaves of turnip, rutabaga, and garden cress. 

By application of first-order, kinetic equations, B. Anderson and Degn claimed that an equilibrated (25°) aqueous solution of D-fructose contains 31.56% of jS-D-fructofuranose and 68.44% of -D-fructopyranose. N.m.r. studies, however, showed that, at equilibrium, a solution of D-fructose contains /3-D-fructopyranose, -D-fructofuranose, a-D-fructofuranose, and a trace of a-D-fructopyranose the distribution of these isomers was shown by gas-liquid chromatography to be 76,19.5, and 4%, respectively. Based on Anderson and Degn s result, Shallenberger reasoned that, as 0.68 X 1.8 = 1.22 (which approximates the reported sweetness of mutarotated D-fructose ), the furanose form(s) must possess very little sweetness. 

Clark et al. [136] studied the excretion, distribution, and metabolism of primaquine in rats. The drug was administered intravenously, intraperitoneally, and orally and blood samples were collected at various time intervals. Primaquine was metabolized by oxidative deamination to give 8-(3-carboxy-l-methylpropylamino)-6-methoxy quinoline. The plasma levels of both primaquine and its metabolites were determined by high performance liquid chromatography. 

Prokai L, Zharikova AD, Janaky T, Prokai-Tatrai K. 2000. Exploratory pharmacokinetics and brain distribution study of a neuropeptide FF antagonist by liquid chromatography/atmospheric pressure ionization tandem mass spectrometry. Rapid Commun Mass Spectrom 14 2412. 

Pharmacokinetic studies (e.g. plasma levels in dogs after peroral or intravenous application, tissue distribution in the rat after intravenous administration) with 44 in several animals have been carried out using l4C-labelled diphenylsilanediol and high pressure liquid chromatography. The elimination half-lives were found to be 1.7 h in mice, 7.2 h in rats, and 6.5 h in dogs after peroral application. 

Platinum-based compounds are commonly used as cancer treatment agents. Pharmacokinetic studies of these antitumor drugs require ultratrace analysis. Electrothermal vaporization ICP-MS provides low detection limits for small samples [256]. High-performance liquid chromatography with ICP-MS detection allows speciation of platinum compounds in tissues [256]. LA-ICP-MS can be used to study the distribution of platinum in tissues and tumors [256]. Natural levels of Pt are below typical quadrupole ICP-MS detection limits [257]. 

Retention volume Change in temperature can affect the distribution of a sample between the mobile and stationary phases and thereby affect retention behavior. In ion-exchange chromatography the effect of temperature is slight, but when the value of the partition ratio depends on adsorption, temperature variation is more significant. In gas-liquid chromatography the effects of temperature have been thoroughly studied, and the fundamental retention relation is... 

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