Determination of Amitraz in Cattle Dipping Baths and Sprays

1978 ◽  
Vol 61 (6) ◽  
pp. 1516-1518
Author(s):  
Michael V Machin ◽  
Kerryn W Mcdougall
Keyword(s):  
Liquid Chromatography ◽  
Petroleum Ether ◽  
Coefficient Of Variation ◽  
Gas Liquid Chromatography ◽  
Chromatographic Methods ◽  
Coefficients Of Variation

Abstract Infrared (IR) and gas chromatographic methods have been developed for determining the acaricide amitraz (N-(2,4-dimethylphenyl)-N - [[(2,4- dimethylphenyl)imino]methyl] - N - methanimidamide) in cattle dip solutions. Extraction with petroleum ether, followed by IR and gas-liquid chromatography (GLC) gave coefficients of variation of 3.4 and 3.6%, respectively, for 0.010-0.035% amitraz. Dilution of the dip sample with acetone and determination by GLC gave a coefficient of variation of 3.6% in the same range. Recovery of amitraz from fortified dip samples was 97–100%.

Rapid Method for Quantitative Determination of Propoxyphene in Serum by Gas-Liquid Chromatography

1973 ◽  
Vol 19 (5) ◽  
pp. 492-495 ◽  
Author(s):  
M A Evenson ◽  
Susan Koellner
Keyword(s):  
Liquid Chromatography ◽  
Quantitative Determination ◽  
Rapid Method ◽  
Coefficient Of Variation ◽  
Therapeutic Dose ◽  
Gas Liquid Chromatography ◽  
Healthy Controls ◽  
Serum Pool ◽  
Sedative Drugs

Abstract Rapid, accurate, and precise gas-chromatographic methods are reported for measurement of propoxyphene ("Darvon") in serum. A sample of 5 ml of serum is required for quantitation in blood after a therapeutic dose of 130-195 mg of propoxyphene; in cases of overdose of propoxyphene, only 1 ml of serum is required in a "toxic method" variation. Neither serum from healthy controls or from hospitalized patients contains interfering substances. Several commonly used analgesic and sedative drugs, added to a serum pool, also did not interfere. Day-to-day precision of the therapeutic method, as measured by the coefficient of variation (CV), is 7%; the CV for the method as applied to overdose cases is less than 3%. Propoxyphene added to serum could be about 86% accounted for analytically.

Determination of Hexachloro-1,3-butadiene in Spinach, Eggs, Fish, and Milk by Electron Capture Gas-Liquid Chromatography

1976 ◽  
Vol 59 (3) ◽  
pp. 552-558
Author(s):  
Martin P Yurawecz ◽  
Peter A Dreifuss ◽  
Laverne R Kamps
Keyword(s):  
Liquid Chromatography ◽  
Petroleum Ether ◽  
Electron Capture ◽  
Mississippi River ◽  
Waste Product ◽  
Official Method ◽  
Gas Liquid Chromatography ◽  
Lower Mississippi River ◽  
Food Commodities

Abstract Hexachloro-1,3-butadiene (HCBD), a waste product formed in the manufacture of perchloroethylene and trichloroethylene, has been found in fish from the lower Mississippi River basin. The AOAC official method for organochlorine pesticide residues in fatty and nonfatty foods has been modified for the determination of HCBD residues in selected food commodities. Acetonitrile extracts of nonfatty foods, or the combined acetonitrile extracts obtained in acetonitrile-petroleum ether partitioning of fat isolated from fatty foods, are diluted with water and extracted with petroleum ether. The petroleum ether extracts are chromatographed on Florisil and HCBD is eluted with petroleum ether. The eluate is analyzed by gas-liquid chromatography with an electron capture detector. Average recoveries of HCBD from fortified samples of fatty and nonfatty foods were greater than 90% in the interlaboratory trials of the method.

scholarly journals Determination of Chlorpyrifos (Diethyl-3,5,6-trichloropyridyl phosphorothioate) in Cured Tobacco

1976 ◽  
Vol 8 (5) ◽  
Author(s):  
Mary J. Toet ◽  
L. Toet
Keyword(s):  
Liquid Chromatography ◽  
Petroleum Ether ◽  
Electron Capture ◽  
Silica Gel ◽  
Electron Capture Detector ◽  
Gas Liquid Chromatography

AbstractA method for determining chlorpyrifos in cured tobacco by gas-Iiquid chromatography, using electron capture and thermionic detection, is described. Ground, cured tobacco, mixed with Florisil, is Soxhlet extracted with acetone for eight hours. The extract is evaporated to dryness, redissolved in a small amount of petroleum ether, and eluted through a silica gel column using first petroleum ether and then 5 % ether in petroleum ether. The volumes of the eluates are adjusted and their chlorpyrifos content determined by gas-liquid chromatography, using an electron capture detector and, for confirmation, a thermionic detector. Recoveries from spiked samples are good, and results are reproducible

HPLC analysis of brain and plasma for octanoic and decanoic acids.

1989 ◽  
Vol 35 (9) ◽  
pp. 1945-1948 ◽  
Author(s):  
H G Dean ◽  
J C Bonser ◽  
J P Gent
Keyword(s):  
Liquid Chromatography ◽  
Detection Limit ◽  
High Performance ◽  
Medium Chain Triglyceride ◽  
Brain Homogenate ◽  
Gas Liquid Chromatography ◽  
Medium Chain ◽  
Detection Analysis ◽  
Coefficients Of Variation

Abstract Two methods are described for determination of octanoic and decanoic acids in plasma and brain homogenate by "high-performance" liquid chromatography with ultraviolet detection. Analysis of the underivatized acids had a detection limit of only 50 mg/L, but formation of the p-bromophenacyl ester increased the sensitivity by 100-fold, to a detection limit of 0.5 mg/L. The latter procedure gave interassay coefficients of variation of 4.1% and 4.8% for octanoic and decanoic acids, respectively. The corresponding intra-assay values were 3.95% and 4.7% (n = 6). The derivative method, applied to samples of plasma from children receiving a medium-chain triglyceride (MCT) diet, gave values in agreement with results by gas-liquid chromatography. Results have also been obtained for samples from mice, either treated with the medium-chain triglyceride diet or given infusions of sodium octanoate.

Collaborative Study of the Determination of Endosulfan, Endosulfan Sulfate, Tetrasul, and Tetradifon Residues in Fresh Fruits and Vegetables

1976 ◽  
Vol 59 (1) ◽  
pp. 209-212
Author(s):  
Lawrence R Mitchell
Keyword(s):  
Liquid Chromatography ◽  
Petroleum Ether ◽  
Electron Capture ◽  
Fruits And Vegetables ◽  
Methylene Chloride ◽  
Collaborative Study ◽  
Gas Liquid Chromatography ◽  
Endosulfan Sulfate ◽  
Florisil Column

Abstract A method for the determination of endosulfan I, endosulfan II, endosulfan sulfate, tetrasul, and tetradifon residues in fresh fruits and vegetables was studied collaboratively. The method consists of extraction of the product with acetonitrile, extract cleanup by partition with petroleum ether and elution from a Florisil column with mixtures of hexane, methylene chloride, and acetonitrile, and determination of the residues by electron capture gas-liquid chromatography. This method was studied by 8 collaborators, using apples and cucumbers as the samples. Each sample was spiked with 2 levels of each pesticide. The average per cent recoveries for apples and cucumbers, respectively, were as follows: endosulfan I, 103.6 and 101.5; endosulfan II, 102.9 and 100.0; endosulfan sulfate, 100.9 and 92.9; tetrasul, 98.8 and 102.2; and tetradifon, 106.4 and 101.9. The method has been adopted as official first action.

Determination of Vitamins D2 and D3 in Pharmaceuticals by Gas-Liquid Chromatography

1968 ◽  
Vol 51 (4) ◽  
pp. 839-840
Author(s):  
T K Murray ◽  
P Erdody ◽  
T Panalaks
Keyword(s):  
Vitamin D ◽  
Liquid Chromatography ◽  
Vitamin A ◽  
Coefficient Of Variation ◽  
Internal Standard ◽  
Antimony Trichloride ◽  
The Other ◽  
Gas Liquid Chromatography ◽  
Partition Chromatography

Abstract A method is described for determining vitamin D in multivitamin preparations; in the method, vitamins D2 and D3 are isomerized with antimony trichloride and separated by GLC. Vitamins D,2 and D3 are differentiated and measured separately and one vitamin may be used as an internal standard for the other. Vitamin A is largely removed by partition chromatography but can be tolerated in the final dilution in a ratio of 1:1 with vitamin D. When the method was used for the assay of multivitamin preparations, the coefficient of variation was 3.2%.

Collaborative Study of Gas-Liquid Chromatographic Determination of Methaqualone in Pharmaceutical and Clandestine Preparations

1977 ◽  
Vol 60 (4) ◽  
pp. 935-939 ◽  
Author(s):  
Harold F Hanel
Keyword(s):  
Liquid Chromatography ◽  
Quantitative Determination ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract Eight laboratories collaboratively studied a procedure for the quantitative determination of methaqualone. HCl in pharmaceutical and clandestine preparations. Methaqualone is extracted from an aqueous bicarbonate solution into chloroform and quantitated by gas-liquid chromatography on a 3% OV-1 column. Tetraphenylethylene is used as an internal standard. Two commercial preparations and 4 sample mixtures prepared by the author were studied. Recoveries for the 4 prepared samples ranged from 100.0 to 102.6%, and the coefficients of variation ranged from 1.58 to 4.15% for the 6 samples studied. The method has been adopted as official first action.

Gas-Liquid Chromatographic Determination of Kepone Residues in Finfish, Shellfish, and Crustaceans

1978 ◽  
Vol 61 (4) ◽  
pp. 877-883
Author(s):  
Richard A Carver ◽  
Arnold P Borsetti ◽  
Laverne R Kamps
Keyword(s):  
Liquid Chromatography ◽  
Standard Deviation ◽  
Petroleum Ether ◽  
Ethyl Ether ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract Finfish, shellfish, and crustacean samples are extracted with isopropanol and benzene; the extract is filtered and then concentrated. The extract, dissolved in hexane, is treated with oleum and extracted with aqueous alkali. The aqueous phase is acidified and extracted with petroleum ether-ethyl ether (1+1). The Kepone residue is determined by electron capture gas-liquid chromatography (GLC). Recoveries obtained by 8 laboratories from 15 species of finfish fortified at 0.02-0.23 ppm ranged from 37 to 107% with a mean ± relative standard deviation of 79.4±14.5%. For oysters fortified at 0.01- 0.10 ppm, recoveries range from 63 to 129% with a mean of 78.2 ±20.8%. For crustaceans fortified at 0.05—0.26 ppm, recoveries ranged from 52 to 110% with a mean of 78.8±16.4%. The approximate limits of quantitation for finfish and for shellfish and crustaceans are 0.02 and 0.05 ppm, respectively, under the GLC conditions used in this study.

A Rapid Method for the Determination of Perhexiline in Serum Using Gas-Liquid Chromatography

1980 ◽  
Vol 17 (3) ◽  
pp. 155-158 ◽  
Author(s):  
J D H Cooper ◽  
D C Turnell
Keyword(s):  
Liquid Chromatography ◽  
Rapid Method ◽  
Limit Of Detection ◽  
Gas Liquid Chromatography ◽  
Single Extraction ◽  
Coefficients Of Variation

A rapid method for the estimation of perhexiline in serum is presented. The procedure employs a single extraction, and no derivatisation is required. The procedure is linear over the range 0·4–4·0 mg/l, and the limit of detection is 0 09 mg/l. The within- and between-batch coefficients of variation at a concentration of 2·0 mg/l were 2·5 and 41%, respectively. Recoveries over the range 0·4–4·0 mg/l produced a mean of 104%. The method is free from interference by other common drugs used in the treatment of angina.

Column Chromatographic Cleanup and Gas-Liquid Chromatographic Determination of Hydroxybenzoic Esters in Food

1973 ◽  
Vol 56 (6) ◽  
pp. 1515-1517
Author(s):  
Paul Daenens ◽  
Leander Laruelle
Keyword(s):  
Liquid Chromatography ◽  
Petroleum Ether ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Hydroxybenzoic Acid ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Acid Esters ◽  
Column Chromatographic

Abstract Hydroxybenzoic acid esters are isolated on a column of silica gel while interferences are removed with petroleum ether. The preservatives are then eluted with petroleum ether-diethyl ether (8+2), derivatives are formed by reaction with bis(trimethylsilyl)acetamide, and the concentrations are determined by gas-liquid chromatography.

Sign in / Sign up

Export Citation Format

Share Document