Collaborative Study of the Gas-Liquid Chromatographic Determination of Malathion in Formulations and Technical Materials

1979 ◽  
Vol 62 (2) ◽  
pp. 292-296
Author(s):  
Richard S Wayne

Abstract A gas-liquid chromatographic method was studied collaboratively for determining malathion in wettable powders, an emulsifiable concentrate, a dust, and the technical grade product. Flame ionization detection, m-diphenoxybenzene as the internal standard, and a column containing 5% SP-2401 or OV-210 on 100-120 mesh Gas-Chrom Q or Supelcoport were used for the determination. Agreement between replicates in individual laboratories was excellent. Agreement between laboratories was satisfactory. The method offers improved specificity and ease of operation when compared to the official first action methods. The method has been adopted as official first action.

1985 ◽  
Vol 68 (3) ◽  
pp. 545-546
Author(s):  
Michael Tsougros

Abstract A stability indicating liquid chromatographic method for the determination of diazepam in tablets was collaboratively studied by 6 laboratories. The method uses a Cig reverse phase column, a methanolwater mobile phase, p-tolualdehyde as the internal standard, and photometric detection at 254 nm. The collaborators were supplied with a synthetic tablet powder and 3 commercial tablet samples. The mean recovery of diazepam from the synthetic tablet powder was 100.2%. For all samples analyzed, the coefficient of variation was < 1.5%. The method has been adopted official first action.


1981 ◽  
Vol 64 (4) ◽  
pp. 829-832
Author(s):  
Bram Van Rossum ◽  
Albertus Martijn ◽  
James E Launer ◽  
◽  
E C Calamita ◽  
...  

Abstract The gas-liquid chromatographic determination of tetradifon technical and formulations was collaboratively studied in duplicate with 12 laboratories. Six samples were dissolved in dichloroethane with n-hexacosane as the internal standard, chromatographed on a column of 3% SE-52, and detected by flame ionization. The average coefficients of variation were 1.2% for the 2 technical samples, 1.6% for the 2 wettable powders, and 1.5% for the 2 emulsifiable concentrates. The method has been adopted official first action.


1985 ◽  
Vol 68 (3) ◽  
pp. 586-589
Author(s):  
Stephen C Slahck

Abstract A liquid chromatographic method for the determination of triadimefon (Bayleton™) in triadimefon technical and formulated products has been developed and subjected to a collaborative study with 7 participating collaborators. Formulations were extracted with mobile solvent and analyzed by normal phase chromatography, with 4-chlorophenyl sulfoxide as an internal standard. Collaborators were furnished with standards and samples of technical products, 50% wettable powders, and 25% wettable powders for analysis. Coefficients of variation of the values obtained on these samples were 1.42, 0.82, and 1.05%, respectively. The method has been adopted official first action.


1984 ◽  
Vol 67 (3) ◽  
pp. 497-499
Author(s):  
Stephen C Slahck ◽  
◽  
J B Audino ◽  
O O Bennett ◽  
B D Folsom ◽  
...  

Abstract A liquid chromatographic method for the determination of propoxur in technical and formulated products has been subjected to a collaborative study with 8 participating collaborators. Formulations are extracted with acetonitrile and analyzed by reverse phase chromatography, with n-butyrophenone as an internal standard. Collaborators were furnished with samples of technical, 70% wettable powder, 1.5 emulsifiable, and 2% bait. Coefficient of variation values obtained on the 4 samples were 0.34, 0.68, 3.25, and 5.41%, respectively. The method has been adopted official first action.


1986 ◽  
Vol 69 (5) ◽  
pp. 908-911
Author(s):  
Peter L Carter ◽  
Keith C Overton ◽  
◽  
P G Baker ◽  
O O Bennett ◽  
...  

Abstract A liquid chromatographic method for determination of bendiocarb in technical materials and wettable powders was tested by 12 collaborators. Bendiocarb is dissolved in acetonitrile containing 0.1% propiophenone as internal standard. This solution is analyzed on a liquid chromatograph utilizing a reverse phase (C18) column. The compound is detected at 254 nm and peak area is used for quantitation. The 3 different materials studied contained 20, 80, and nominally 100% bendiocarb. Each was examined in duplicate to provide the necessary matched pairs. Collaborators approved of the ease and simplicity of the method and, in particular, the way the method can be applied to automatic injection assemblies. The statistical data show acceptable precision of the method: Reproducibility coefficients of variation were 20% material, 2.04%; 80% material, 1.02%; and nominal 100% material (technical product), 0.64%. The method has been adopted official first action.


1988 ◽  
Vol 71 (1) ◽  
pp. 33-35
Author(s):  
Donald Shostak ◽  
Clifford Klein ◽  
◽  
C Cappon ◽  
N Falcone ◽  
...  

Abstract A liquid chromatographic method for the determination of flucytosine in capsules was collaboratively studied by 7 laboratories. The method uses a C18 reverse phase column, water-methanol-acetic acid mobile phase containing 1-octanesulfonic acid sodium salt, p-aminobenzoic acid as internal standard, and photometric detection at 285 nm. The mean recovery value (±SD) of flucytosine from a synthetic formulation representing capsules was 99.2 ± 1.72% (CV = 1.73%). Composited samples of 250 and 500 mg commercial capsules gave assay values of (mean ± SD) 103.17 ± 2.21 and 99.29 ± 1.29% of declared, respectively. CV values were 2.15 and 1.30%. Reproducibility and repeatability CVs were 2.19 and 1.50%, respectively, for the 250 mg capsules, and 1.34 and 0.63%, respectively, for the 500 mg capsules. The method has been adopted official first action.


1972 ◽  
Vol 55 (1) ◽  
pp. 166-169
Author(s):  
William T Lampkin

Abstract A collaborative study was conducted on a GLC method for determining paraldehyde in pharmaceutical preparations of paraldehyde elixirs. Eleven collaborating laboratories analyzed 2 unknown paraldehyde solutions and a solution of known paraldehyde concentration. Recoveries of 15–25% paraldehyde solutions averaged 98.5% with a coefficient of variation of about 2%. The method consists of diluting a sample aliquot to a definite volume and determining the paraldehyde content by GLC, using a flame ionization detector and a 6’ × 4 mm coiled glass column packed with 80–100 mesh Diatoport S coated with 2% HIEFF-8BP (cyclohexane dimethanol succinate) plus 20% Carbowax 20M. The internal standard technique was used for calculation. It is recommended that the method be adopted as official first action.


1982 ◽  
Vol 65 (2) ◽  
pp. 249-255
Author(s):  
Vernon J Meinen ◽  
Dean C Kassera ◽  
◽  
P Anderson ◽  
J B Audino ◽  
...  

Abstract A gas-liquid chromatographic method is described for the quantitative determination of pyrethrins and piperonyl butoxide in various formulations. The samples are diluted in acetone and analyzed by gas chromatography, with a flame ionization detector and a column packed with OV-101 or OV-1 on Chromosorb W (HP). The method was collaboratively studied with technical piperonyl butoxide and 3 pyrethrin-piperonyl butoxide formulations. The coefficients of variation for piperonyl butoxide ranged from 1.36 to 3.41% for the 5 samples. For pyrethrins in 3 formulations, the coefficients of variation were 2.20, 4.73, and 2.22%. An examination of the t-values indicated little or no contribution to systematic error, with the exception of one formulation. The method has been adopted official first action.


1980 ◽  
Vol 63 (4) ◽  
pp. 869-872
Author(s):  
Thomas L Jensen ◽  
◽  
J B Audino ◽  
R Bishop ◽  
L Chenery ◽  
...  

Abstract A rapid method is described for the determination of disulfoton (0,0-diethyl S-[2-(ethylthio)-ethyl] phosphorodithioate) in formulations by gasliquid chromatography (GLC). Samples are dissolved in acetone, and, after an internal standard is added, the samples are diluted to volume with solvent. They are then injected into a gas chromatograph equipped with a flame ionization detector and quantitated by peak height or area measurements. Fourteen collaborators made duplicate determinations on 4 samples including the technical product, a liquid, and 2 granular formulations. The average coefficient of variation was 0.847% for the liquid samples and 1.90% for the granules. The method has been adopted as official first action.


1984 ◽  
Vol 67 (6) ◽  
pp. 1121-1122
Author(s):  
Donald Shostak ◽  
◽  
M P Uribe ◽  
T Poplawski ◽  
T S Savage ◽  
...  

Abstract A liquid chromatographic method for the determination of allopurinolin tablets was collaboratively studied by 7 laboratories. The methoduses a C,8 reverse phase column, a 0.05M ammonium phosphate mobilephase, hypoxanthine as the internal standard, and photometric detectionat 254 nm. Collaborators were supplied with samples of 2 commercialtablets and 1 synthetic tablet powder. The mean recovery value of allopurinol from the synthetic tablet powder was 100.0%. The combinedmean coefficient of variation for all 3 types of sample analyzedwas less than 2%. The method has been adopted official first action.


Sign in / Sign up

Export Citation Format

Share Document