Fehlermöglichkeiten bei der quantitativen Analyse polycyclischer aromatischer Kohlenwasserstoffe aus Luftstaubextrakten mit der Capillar-Gas-Chromatographie

Isolation of polycyclic aromatic hydrocarbons in air particulate matter by liquid chromatography

“…The results showed that the total amount which was processed ranged from 20 ng (benzo[bjfluorene) to 300 ng (benzofluoranthenes) per individual PAH. The quantitative results have been proven to be the same within the standard deviation when applying the more time-consuming cleanup procedures described in previous studies (8). With the gas chromatographic quantification limit taken into account, e.g., ~1 ng of benzo[o]pyrene (BaP) in these complex mixtures, the concentrations for the relevant PAH in the crude sample-processed by the new cleanup procedure-should not be lower than 20 ng.…”

“…More recently, RIA (3)(4)(5)(6)(7). GLC (8) and high-performance liquid chromatography (HPLC) (9,10) methods have been reported for glyburide in plasma or serum.…”

“…Although several of the radioimmunoassays are sufficiently sensitive for therapeutic drug monitoring (4,6,7), all of these methods suffer to some degree from lack of specificity because of one or more of the following reasons: (1) cross-reactivity with known metabolites of glyburide (3-5); (2) nonspecific binding to plasma proteins (4, 6); (3) crossreactivity with other sulfonylureas (6,7). The GLC method that was developed for the analysis of glyburide in human plasma requires reaction of the drug with 2,4-dinitrofluorobenzene to form a volatile, thermally stable derivative that is suitable for electron-capture detection (8). This methodology provides high sensitivity and the known metabolites 1 Senior Independent Project Participant, Department of Chemistry, Kalamazoo College, Kalamazoo, MI 49007.…”

“…This paper describes a one-step cleanup procedure which separates the PAH amounts at nanogram levels, found on airborne particles, from interfering compounds within 1 h. This is performed by an atypic gel chromatography starting directly with the crude extract. This fraction was as "pure" as the one obtained by the time-consuming method applied in our laboratory up to now (8). EXPERIMENTAL…”

Gas chromatographic mass spectrometric determination of high-molecular-weight polycyclic aromatic hydrocarbons in coal tar

“…EXPERIMENTAL SECTION A 1.3-g sample of coal tar was extracted, using a mixture of cyclohexane (500 mL) and benzene (10 mL). Further treatment and fractionation of this extract followed the procedures for isolating PAH from airborne particles as described elsewhere (22). The last step of this cleanup procedure was however modified as follows: By the use of column chromatography on Sephadex LH-20 (82 X 2.5 cm; propanol-2; flow rate 1 mL/min) three PAH fractions with components of molecular weights higher than 300 were obtained by collecting the eluate from 1.2 to 1.8 L, from 1.8 to 2.4 L, and from 2.4 to 4.4 L. To analyze the unseparated PAH fractions exclusively by mass spectrometry (Finnigan, Model 4021) a direct insertion probe with a glass capillary was utilized under the following conditions: the temperature was raised ballistically from 80 to 260 °C and held at 260 °C; scan range 280 to 600 amu: scan time 5 s; ionizing energy 18 eV (Figure 1).…”