Blood cultures from 196 patients with suspected bacteraemia or septicaemia were analysed by automated head-space gas chromatography, using a 25 m fused silica capillary column, when turbidity indicated growth. Gas chromatography correctly identified 105 cultures as positive and 71 correctly as negative. No false-positive results were obtained. Of the 20 false-negative chromatographic results, S...

We propose a chromatographic method for the separation of saturated and unsaturated fatty acids by a high-performance liquid chromatography system, equipped with a photo diode array detector. Central to the method is the use of an appropriate mobile phase composed of acetonitrile, methanol, and n-hexane in ratio 90:8:2 acidified with 0.2% acetic acid, which allows the detection of fatty acids w...

A sensitive gas chromatographic method using an electron-capture detector (ECD) has been developed for the determination of tetraconazole and diniconazole fungicide residues in tomatoes and green beans. The developed method consists of extraction with methanol, partition with methylene chloride, and column chromatographic clean-up, followed by capillary gas chromatographic determination. The re...

A gas chromatographic method is described for the direct quantitative determination of the partial pressure of halothane (or isoflurane) in blood as well as the blood-gas partition coefficient. A head space technique and a flame ionization detector were used. Standard blood was obtained by equilibrating patients' blood with known gas concentrations in a tonometer. Using an infra-red analyser to...

A method ispresentedfor determining those volatile components of Jbods that have flavour significance. The method leads to quantitative flavour specifications called charm that can be displayed graphically. The procedure is baaed upon the relative odour detection thresholds of volatile compounds of known gas chromatographic retention indices.

We describe a convenient method for the direct determination of the serum cholesterol linoleate/cholesterol oleate (L/O) ratio by reversed-phase "high-performance" liquid chromatography. After removal of phospholipids by silicic acid chromatography, a serum extract is analyzed on a 5-micrometers particle size Ultrasphere-ODS column, eluted isocratically with acetonitrile/isopropanol (30/70, by ...

In studies on endogenous plant gibberellins (GAs), reverse phase (Bondapak C(18)) high performance liquid chromatography (HPLC) has proved to be a useful method for the fractionation of plant extracts. The behavior of 18 authentic GAs in such a chromatographic system is described. The main factors determining chromatographic behavior are the degree and the position of hydroxylation of the GA. G...