Microdetermination of phosphine by gas-liquid chromatography with microcoulometric, thermionic, and flame photometric detection

Abstract The Onley-Yip procedure for determining ethylenethiourea (ETU) in milk and crops was modified to reduce interferences by the ethylenebisdithiocarbamates (EBDCs). A 20 g cropmethanol extract is cleaned up by adsorbing the sample onto Gas-Chrom S, desorbing ETU, and eluting ETU from aluminum oxide with chloroform containing ethanol. ETU is converted to the S-butyl derivative for gas-liquid chromatography (GLC) and flame photometric detection (sulfur mode). For liquid chromatography (LC), ETU is cleaned up on another aluminum oxide column and injected directly. LC and GLC results are confirmed by thin layer chromatography. A cooking procedure based on conversion of EBDCs to ETU is included for surveying crops for possible EBDC content. Recoveries from 8 crops and milk fortified at 0.05 ppm ETU ranged from 73 to 100%.

Download Full-text

Gas-Liquid Chromatography and Flame Photometric Detection of Phosphine in Wheat

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/61.4.829 ◽

1978 ◽

Vol 61 (4) ◽

pp. 829-836 ◽

Cited By ~ 1

Author(s):

Thomas W Nowicki

Keyword(s):

Liquid Chromatography ◽

Screening Method ◽

Gas Liquid Chromatography ◽

Gas Chromatograph ◽

Aluminum Phosphide ◽

Photometric Detection ◽

Residual Aluminum ◽

Flame Photometric Detection ◽

Rubber Septa ◽

Electronic Integrator

Abstract A screening method using gas-liquid chromatography with flame photometric detection has been developed for determining phosphine in wheat. Phosphine is measured as the sum of physically bound intact phosphine and that derived from residual aluminum phosphide. Wheat is extracted in a closed, partially evacuated glass system by refluxing with 10% sulfuric acid. Liberated gases are swept into a gas-collection flask fitted with rubber septa to permit gas sampling. Aliquots of collected gas are injected into a gas chromatograph. Phosphine is quantitated by peak area as determined by an electronic integrator. Recoveries varied with concentration: 67% was recovered at 0.10 ppm and 98% was recovered at 19 ppm. For concentrations less than 1.5 ppm, the coefficient of variation was 9.95%. Using flame photometric detection, phosphine concentrations as low as 0.04 ppm were easily determined in wheat.

Download Full-text

Pyrolysis gas-liquid chromatography of the pathotypes of the potato cyst nematodesGlobodera rostochiensisandG. pallida

Parasitology ◽

10.1017/s0031182000062752 ◽

1985 ◽

Vol 91 (3) ◽

pp. 507-518 ◽

Cited By ~ 3

Author(s):

P. C. Fox ◽

H. J. Atkinson

Keyword(s):

Liquid Chromatography ◽

Gas Liquid Chromatography ◽

Potato Cyst Nematodes ◽

Cyst Nematodes ◽

Pyrolysis Gas ◽

Detection Systems ◽

Photometric Detection ◽

Flame Ionization ◽

Flame Photometric Detection ◽

Curie Point Pyrolysis

SUMMARYCurie-point pyrolysis gas-liquid chromatography (PGLC) was used to detect gross chemical differences between the 8 European pathotypes of the potato cyst nematodesGlobodera rostochiensisandG. pallida. No qualitative differences were seen with either flame ionization or flame photometric detection systems, although quantitative differences between pathotypes were detected. Cluster analysis of these differences failed to group the pathotypes into species, but separation of some economically important pathotypes was achieved. The potential of PGLC for nematode identification is discussed.

Download Full-text

Gas—liquid chromatography of thiols using flame-photometric detection and a deactivated transfer line

Journal of Chromatography A ◽

10.1016/s0021-9673(00)92342-2 ◽

1978 ◽

Vol 157 ◽

pp. 267-275 ◽

Cited By ~ 8

Author(s):

J.W. Gramshaw ◽

Altaf Hussain

Keyword(s):

Liquid Chromatography ◽

Gas Liquid Chromatography ◽

Photometric Detection ◽

Transfer Line ◽

Flame Photometric Detection

Download Full-text

Phosphorylation of Alcohols/Phenols for Gas-Liquid Chromatographic Separation and Flame Photometric Detection

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/61.1.210 ◽

1978 ◽

Vol 61 (1) ◽

pp. 210-213

Author(s):

Padmakar G Deo ◽

Philip H Howard

Keyword(s):

Liquid Chromatography ◽

Chromatographic Separation ◽

Gas Liquid Chromatography ◽

Alkyl Aryl ◽

Flame Photometric Detector ◽

Photometric Detection ◽

Photometric Detector ◽

Liquid Chromatographic Separation ◽

Flame Photometric Detection ◽

Liquid Chromatographic

Abstract A new procedure is presented for the gas-liquid chromatographic separation of alcohols and phenols, using phosphorylation by diethyl chlorophosphate. Alcohols/phenols were phosphorylated by a base-catalyzed reaction with diethyl chlorophosphate, and the resulting alkyl/aryl diethyl phosphates were separated by gas-liquid chromatography and detected by a flame photometric detector supplied with a 526 nm filter. For seven alcohols/phenols tested, quantities as low as 10–25 ng were easily detected.

Download Full-text