acetonitrile used as a solvent in manufactures and affects to central nervous system from inhalation exposure. the aim of this study was to develop a micro-solid phase extraction method for  the determination of acetonitrile in the air matrix. the sampling was performed with a small diameter fused silica fiber coated with a thin film of stationary phase and was subsequently desorbed and analyze...

in this study, caffeic acid (ca) and its three derivatives including 3-caffeoylquinic acid (3-cqa, neochlorogenic acid), 4-caffeoylquinic acid (4-cqa, cryptochlorogenic acid), and 5-caffeoylquinic acid (5-cqa, chlorogenic acid) were identified in bupleurum chinense aerial parts using reverse-phase high-performance liquid chromatography (rp-hplc) with photodiode array (pda) detector, reference c...

Catecholamines and their metabolites have been separated isocratically by reverse-phase chromatography with aqueous (no organic solvent admixed) eluents. Unlike ion-exchange or ion-pair chromatography, mixtures of both acidic and basic substances can be separated in a single chromatographic run, because the retention is governed by hydrophobic interactions between the nonpolar moiety of the sol...

Pepticinnamins A, B, C, D, E and F, a family of farnesyl-protein transferase (FPT) inhibitors were isolated from the fermentation broth of Streptomyces sp. OH-4652. These inhibitors were purified from whole broth by extraction with chloroform, followed by silica gel column chromatography, Sephadex LH-20 chromatography and reverse phase HPLC. Among these, pepticinnamin C showed the most potent i...

Cytoplasmic rRNA from the yeast mutant, mod5-1 is deficient in the modified base isopentenyladenosine and consequently migrates differently from isopentenylated wild type tRNAs on certain chromatographic systems. To determine if the mod5-1 mutation affects mitochondrial tRNA structure, the migration of mitochondrial tRNA from mod5-1 and wild type cells has been compared by reverse-phase chromat...

Synthetic and analytical approaches were used to characterize the tumor-localizing components of the porphyrin preparation, hematoporphyrin derivative. From studies involving aqueous and nonaqueous gel exclusion and reverse-phase chromatography, we conclude that localization is mediated by hematoporphyrin derivative components which are among the most hydrophobic in the preparation. This appare...

Synthetic and analytical approaches were used to characterize the tumor-localizing components of the porphyrin preparation, hematoporphyrin derivative. From studies involving aqueous and nonaqueous gel exclusion and reverse-phase chromatography, we conclude that localization is mediated by hematoporphyrin derivative components which are among the most hydrophobic in the preparation. This appare...