Phosphorus selectivity

Kataoka H. 1997. Selective and sensitive determination of protein and non-protein amino acids by capillary gas chromatography with nitrogen—phosphorus selective detection. Biomed Chromatogr 11 154. 

Ulrich S. 2003. Direct stereoselective assay of fluoxetine and norfluoxetine enantiomers in human plasma or serum by two-dimensional gas-liquid chromatography with nitrogen-phosphorus selective detection. J Chromatogr B 783 481. 

The extracts were also analyzed for OPs and TAAPs by capillary GC equipped with a nitrogen-phosphorus selective detector (GC-NPD) (6, 8). 

Phosphorus selectivity to hydrocarbons is 105 1. Effects of quenching and self-absorption have not been detailed in the literature. 

S. Ulrich and J. Martens, Solid-phase microextraction with capillary gas-liquid chromatography and nitrogen-phosphorus selective detection for the assay of antidepressant drugs in human plasma , J. Chromatogr. B 696 217-234 (1997). 

F enitrothion,Aminocarb and phenolic hydrolyses products Nitrogen- phosphorus selective detector Phenols derivitivised to esters with aceticanhydride then methylene chloride extraction, then GLC I 8 [449]... 

Most OP insecticides may be determined directly by GC using the phosphorus-selective flame photometric detector (FPD) which helps to minimize clean-up. However, it must be emphasised that the FPD is only a "selective" detector for phosphorus (at 540 nm) or sulphur (at 394 nm) and not an "element specific detector". 

Tarbah et al. also used a single-step liquid-liquid extraction method with toluene for the determination of 23 OPi in urine, blood, serum and food samples using GC with nitrogen-phosphorus selective detection (GC-NPD) and electron ionization mass spectrometry (GC-EIMS). The recoveries for spiked human plasma ranged between 50% (demetho-ate) and 133% (dialifos). Akgur et al successfully measured OP concentrations in 28 cases of acute OP poisoning using the above application. 

Detectors such as laser fluorometry, FT-IR, mass spectrometer and flame-based detectors can be used to obtain desired selectivity and resolution. A phosphorus-selective detector for HPLC can provide ultrahlgh resolution. In the phosphorus-selective chromatogram, the analyte peak is well resolved from neighboring peaks and the slgnal-to-nolse ratio Is also much higher than for the RI detector (13). 

The formation of cyan anions can be suppressed by increasing the reaction temperature with an increased flow of hydrogen (electrical heating of the bead is unnecessary under these conditions) allowing a phosphorus selective mode of operation. The jet is usually grounded under this mode. 

Nucleophilic substitution of two chlorine atoms of 1-dichlorophosphino moiety of 63 (X = CH) could be possible by reacting it with methanol in the presence of EtjN. The resulting 1-dimethoxyphosphino derivative was subjected to Mel-catalyzed Arbuzov rearrangement and could be oxidized with sulfur at the exocy-clic phosphorus selectively [76],... 

Since Kosolapoff s classic summary of the chemistry of organophosphorus compounds (116), many advances in the techniques required for study of these materials have been developed. Selective displacement of halide ions and/or alkoxy (or aryloxy) groups from a phosphorus atom by organometallic reagents is a convenient process of synthetic importance for an enormous variety of organophosphorus compounds. Only within the past few years has data been made available on the mechanism of this type of reaction, but further study is necessary for a complete interpretation. We have attempted to correlate the existing information with emphasis on synthetic utility and application to the manner of displacement of halide ion and OR groups attached to phosphorus. Selection of examples for discussion is arbitrary, of course, but an attempt was made to include topics for which... 

Figure 7. Gas chromatogram of pyrrolizidine alkaloids from comfrey root tea. Nitrogen-phosphorus selective detector all other conditions identical to those...

Formerly, a GC method with nitrogen-phosphorus selective detector (NPD) was developed for the determination of HCAs with the advantage of the high response of these compounds in the detector due to the nitrogen atoms present in the structure of the HCAs. Kataoka and Kijima developed a simple and rapid derivatiza-tion method for GC analysis of HCAs. Ten HCAs were converted into their A-dimethylaminomethylene derivatives with A,A-dimethylformamide dimethylac-etal and measured by GC with NPD using two connected fused silica capillary columns in order to improve the separation of HCAs [115]. The structures of the HCAs derivatives were confirmed by GC-MS. 

Kataoka, H. and Kijima, K. 1997. Analysis of heterocyclic amines as their N-dimethylaminomethylene derivatives by gas chromatography with nitrogen-phosphorus selective detection. J. Chromatogr. A 767 187-194. 

Bianchetti, G., and Morselli, P. L. Rapid and Sensitive Method for Determination of Haloperidol in Human Samples Using Nitrogen-Phosphorus Selective Detection... 

Comparison of Gas-Liquid Chromatography with Nitrogen-Phosphorus Selective Detection and High-Performance Liquid Chromatography Methods for Caffeine Determination in Plasma and Tissues... 

Simple and Sensitive Method for the Determination of Cyclophosphamide by Means of a Nitrogen-Phosphorus-Selective Detector... 

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