The PFPD has advantages over the other two phosphorus sensing GC detectors: 1) the Thermionic Specific Detector (TSD), a nitrogen-phosphorus detector, and 2) the Flame Photometric Detector (FPD). Comparisons are made between these detectors. Finally, high speed data acquisition firmware and software that allows one to easily set up the PFPD and review the pulsed emission data emanating from eac...

Migration patterns of nutrient elements, viz. (59)Fe, (54)Mn, (65)Zn, and (86)Rb, supplied to young corn (Zea mays) leaves were studied using a modified chromatogram scanner. It was found that the isotopes supplied to one-half of the leaf did not migrate to the other side across the midrib, but moved generally toward the base of the applied part of the leaf.

chromatography (UHPLC) has taken a firm foothold in the analytical laboratory. However, it is rare that 100% of instrumentation within a company is all from the same vendor and of the same model. Differences between equipment can lead to unexpected changes in the chromatogram when a method is transferred from one system to another. In this issue of Separation Science we examine these issues and...

cis-Reticulatacin-10-ones A and B were synthesised as a predefined mixture of diastereoisomers (dr ∼ 1 : 9) in nine steps from the acid chloride 8, and without the use of hydroxyl protecting groups. Comparison of the chiral HPLC chromatogram of the synthetic sample with that of the natural product isolated from the roots of the tropical fruit tree Annona muricata L. showed the natural product t...

Hydroxylamines gradually undergo oxidation to their oximes on being dissolved in organic solvent (e.g. methanol). This phenomenon was followed by (1)H-NMR and liquid chromatography-mass spectrometry (LC-MS). The oxidation rate was estimated from the peak area observed on the mass chromatogram at the protonated molecule or fragment ion on LC-atmospheric pressure chemical ionization (APCI)-MS. Th...

Fig. 6. Analysis of the volatile amines present in Chenopodium vulvaria L. Curve A: standard mixture ofmono-, diand tri-methylamines. Curve B: chromatogram of the amines present in an acid extract ofthe plant, showing the presence of only ammonia and trimethylamine. (Column length, 4ft.; liquid phase, hendecanol-iS% liquid paraffin (v/v); temp., 78 50; flow rate of nitrogen, 5.7 ml./min.; nitro...

We describe a sensitive, simple technique for determining urinary oxalate. Urine, diluted as necessary with distilled water, is injected into an ion chromatograph. Oxalate is detected conductimetrically as a distinct peak near the tail of the chromatogram. This peak specifically represents oxalate, because it is abolished if the sample is treated with oxalate decarboxylase. We have used this te...

Department of Organic Chemistry II, Unive P.O. Box 644, 48080 Bilbao, Spain Departamento de Śıntesis y Estructura de Bi y Catálisis Homogénea (ISQCH), Universida Servicio de Resonancia Magnética Nuclear, C (CEQMA), Universidad de Zaragoza, CSIC, † Electronic supplementary information procedures and characterization of all NMR spectra and HPLC chromatogram Cartesian coordinates of all stationary...

During the evaluation of the continuous measurement signal of analytical instruments by a digital computer, the signal is sampled periodically, and the analytical information [1] is computed from this sequence of discrete values representing the signal by the procedure called data reduction [2]. For example, retention data, peak heights and/or peak areas are produced from the raw discretized si...