Nitrogen selective detector

Marano RS, Levine SP, Harvey TM. 1978. Trace determination of subnanogram amounts of acrylonitrile in complex matrices by gas chromatography with a nitrogen-selective detector. Anal Chem 50 1948-1950. 

Thermal Energy Analysis and Nitrogen-Selective Detectors 381... 

Gas chromatography is one of the most powerful analytical techniques available for chemical analysis. Commercially available chemiluminescence detectors for GC include the FPD, the SCD, the thermal energy analysis (TEA) detector, and nitrogen-selective detectors. Highly sensitive detectors based on chemiluminescent reactions with F2 and active nitrogen also have been developed. 

The NO + 03 chemiluminescent reaction [Reactions (1-3)] is utilized in two commercially available GC detectors, the TEA detector, manufactured by Thermal Electric Corporation (Saddle Brook, NJ), and two nitrogen-selective detectors, manufactured by Thermal Electric Corporation and Antek Instruments, respectively. The TEA detector provides a highly sensitive and selective means of analyzing samples for A-nitrosamines, many of which are known carcinogens. These compounds can be found in such diverse matrices as foods, cosmetics, tobacco products, and environmental samples of soil and water. The TEA detector can also be used to quantify nitroaromatics. This class of compounds includes many explosives and various reactive intermediates used in the chemical industry [121]. Several nitroaromatics are known carcinogens, and are found as environmental contaminants. They have been repeatedly identified in organic aerosol particles, formed from the reaction of polycyclic aromatic hydrocarbons with atmospheric nitric acid at the particle surface [122-124], The TEA detector is extremely selective, which aids analyses in complex matrices, but also severely limits the number of potential applications for the detector [125-127],... 

Lehane, D.P. et al. 1976. Therapeutic drug monitoring Measurements of antiepileptic and barbiturate drug levels in blood by gas chromatography with nitrogen-selective detector. Ann Clin Lab Sci. 6 404. 

Calverly and Denny [199] have described a rapid and sensitive procedure for the determination of residue levels of three uracil herbicides in soils. After addition of calcium hydroxide and Celite to the soil the herbicides are eluted from columns with water. After acidification of the eluate and partition into chloroform these herbicides are determined by gas chromatography using a nitrogen-selective detector. Recoveries from a range of soil types are better than 80%, with a sensitivity limit of 20pg kgy1. 

An example of the use of GC with nitrogen selective detection is in the quantification of bupivacaine in plasma. Bupivacaine contains two nitrogen atoms in its structure which makes it a good candidate for this type of analysis. The limits of detection which can be achieved with a nitrogen selective detector for this compound are much better than methods based on flame ionisation detection, which are much less selective. 

Gas chromatographic methods have been successfully used for the determination of penicillin molecules bearing neutral side-chains in milk and tissues (95, 97), but cannot be used for amphoteric -lactams. Gas chromatography of penicillin residues is further complicated by the necessity for derivatization with diazomethane. This derivatization step is particularly important because it not only leads to formation of the volatile penicillin methyl esters but also improves their chromatographic properties (thermal stability and decreased polarity). Using a fused-silica capillary column in connection with a thermionic nitrogen-selective detector, excellent separation and sensitivity figures were obtained. 

The carboxin is extracted from the sample with acetone in a Soxhlet extraction apparatus and, after concentration of the extract, is determined via gas-liquid chromatography using a nitrogen-selective detector. The presence of carboxin is confirmed by the use of a sulfur flame photometric detector. Recoveries ranged from 73 to 80% (barley) and 73 to 78% (wheat). 

U.S. EPA Method TO7 describes the determination of N-nitrosodimethylamine in ambient air (U.S. EPA, 1986). The method is similar to the NIOSH method discussed above and uses Thermosorb/N as adsorbent. The air flow is 2 L/min and the sample volume recommended is 300 L air. The analyte is desorbed with methylene chloride and determined by GC/MS or an alternate selective GC system, such as TEA, HECD, or thermoionic nitrogen-selective detector. The latter detector and the TEA are more sensitive and selective than the other detectors. Therefore, the interference from other substances is minimal. Other nitrosamines in air may be determined in the same way. 

De Leenheer, A. P., and Celijkens, C. F. (1978). Quantification of 5-Fluorouridine in Human Urine by capillary gas-liquid chromatography with a nitrogen-selective detector. J. Chromatogr. Sci. 16, 552-555. 

Data from specific detectors (e.g., electrochemical, fluorescence, nitrogen-selective detectors)... 

Detectors which are sensitive to specific elements or structures, such as electron capture detectors (ECD) or phosphorus- and nitrogen-selective detectors (TSD) respond even to quantities of substances in the picogram (10"12 g) Qj. femtogram (10 g) ranges. 

TEA, thermal energy analyzer NSD, nitrogen selective detector RCD, redox chemiluminescence detector. 

A gas chromatograph (GC), equipped with a nitrogen selective detector. A Hewlett-Packard Model 5840A GC fitted with a nitrogen-phosphorus flame ionization detector (NPD) was used for this evaluation. Injections were performed using a Hewlett-Packard Model 7671A automatic sampler. 

Ultramicro GC Determination of Amino Acids Using Glass Open Tubular Columns and a Nitrogen-Selective Detector... 

Bertrand, M., Masse, R., and Dugal, R. Computerized Gas Chromatographic Screening of Volatile Stimulants, Sympathomimetic Amines and Narcotic Analgesics Using a Nitrogen Selective Detector... 

Wall-Coated Open Tubular Columns Coupled with Nitrogen-Selective Detector for Routine GLC Determination of Diazepam, Meprobamate, Phenylbutazone, and Thioridazone in Serum J. Pharm. Sci. 69(7) 835-838 (1980) ... 

Determination of Hexamethylmelamine and Metabolites in Plasma or Serum by Gas-Liquid Chromatography with a Nitrogen-Selective Detector J. Chromatogr. 181(3-4) 363-371 (1980) CA 92 208679k... 

Simultaneous GLC Determination of Phenylpropanolamine and Chlorpheniramine in Urine Using a Nitrogen Selective Detector J. Pharm. Sci. 67(1) 118-119 (1978) ... 

Therapeutic Drug Monitoring Measurement of Antiepileptic and Barbiturate Drug Levels in Blood by Gas Chromatography with Nitrogen-Selective Detector... 

Organic Nitrogen-Selective Detector Used in Gas Chromatographic Determination of Some Anticonvulsant and Barbiturate Drugs in Plasma and Tissues... 

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