Gas-Liquid Chromatographic Determination of Benzoic Acid and Sorbic Acid in Foods: NMKL1 Collaborative Study

1983 ◽  
Vol 66 (3) ◽  
pp. 775-780
Author(s):  
Bonny K Larsson ◽  
◽  
M Askeland ◽  
M Bergstrøm-Nilsen ◽  
H K Dahle ◽  
...  
Keyword(s):  
Benzoic Acid ◽  
Apple Juice ◽  
Methylene Chloride ◽  
Sorbic Acid ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Caproic Acid ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic

Abstract A gas-liquid chromatographic method for the simultaneous determination of benzoic acid and sorbic acid in foods was collaboratively studied by 8 laboratories. Benzoic and sorbic acids are isolated from food by successive extractions with ether, sodium hydroxide, and methylene chloride, converted to trimethylsilyl (TMS) esters, and determined by gasliquid chromatography. Phenylacetic acid and caproic acid are used as internal standards for benzoic acid and sorbic acid, respectively. Seven samples were collaboratively studied: almond paste, fish homogenate, and apple juice with benzoic and sorbic acid levels from 0.04 to 2 g/kg. Average recoveries {%) for benzoic and sorbic acids were as follows: almond paste, 99.6 and 101.2; fish homogenate, 99.2 and 97.4; and apple juice 98.2 and 106.6. The reproducibility coefficients of variation (%) for benzoic and sorbic acids at 0.5-2 g/kg levels were 3.5-6.1 and 5.2-9.0; and at the 0.04 g/kg level, 14.7 and 23.3, respectively. The method has been adopted official first action at 0.5-2 g/kg levels.

Liquid Chromatographic Determination of Major Organic Acids in Apple Juice and Cranberry Juice Cocktail: Collaborative Study

1986 ◽  
Vol 69 (4) ◽  
pp. 594-597 ◽  
Author(s):  
Elia D Coppola ◽  
Martin S Starr ◽  
◽  
G H Chang ◽  
J DeVries ◽  
...  
Keyword(s):  
Apple Juice ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Cranberry Juice ◽  
Coefficients Of Variation ◽  
Silica Cartridge ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract Twelve laboratories collaboratively studied a liquid chromatographic method for determination of quinic, malic, and citric acids in cranberry juice cocktail and apple juice. Samples are passed through a disposable silica cartridge, filtered, and directly injected into the chromatograph. The mobile phase is 0.2M KH2PO4 (pH 2.4). Two reverse phase columns are used, with UV detection at 214 nm. Six samples of cranberry juice cocktail and 6 samples of apple juice were sent to each collaborator. Repeatability and reproducibility coefficients of variation ranged from 1.2 to 7.6% and from 2.9 to 14.7%, respectively, for quinic, malic, and citric acid levels above 0.10%. The precision of the method is satisfactory. The method has been adopted official first action.

Liquid Chromatographic Determination and Identification Tests for Dexamethasone in Bulk Drugs and Elixirs: Collaborative Study

1987 ◽  
Vol 70 (6) ◽  
pp. 967-973
Author(s):  
Elaine A Bunch
Keyword(s):  
Methylene Chloride ◽  
Collaborative Study ◽  
Internal Standard ◽  
Dosage Level ◽  
Chromatographic Determination ◽  
Photometric Detection ◽  
Coefficients Of Variation ◽  
Bulk Drug ◽  
Liquid Chromatographic

Abstract A normal phase liquid chromatographic method for the determination of dexamethasone in bulk drugs and elixirs was collaboratively studied by 6 laboratories. The method uses a silica column, water-modified acetic acid-methanol-methylene chloride mobile phase, cortisone internal standard, and photometric detection at 254 nm. Collaborators were supplied blind duplicate samples of 3 bulk drugs, 2 commercial elixirs, and 1 authentic elixir. Dexamethasone elixir dosage level is 0.5 mg/5 tnL. Mean recovery of dexamethasone from the authentic elixir formulated to contain 0.471 mg/5 mL was 94.5%. (Authentic elixirs were found to stabilize about 6% below the theoretical concentration.) Mean recovery for the bulk drugs was between 97.1 and 100.1%. Mean coefficients of variation for bulk drug and elixir samples were less than 0.8% and 3.6%, respectively. Identification tests for dexamethasone by thin-layer chromatography, infrared spectroscopy, and relative LC retention times, as well as the gas chromatographic determination of alcohol in the elixirs were also collaboratively studied. Mean recovery of alcohol from the synthetic elixir was 98.6%. The mean coefficient of variation for alcohol for all samples analyzed was less than 1.4%. The LC method for dexamethasone in drug substance and elixirs, the identification tests, and the GC method for alcohol in dexamethasone elixirs have been adopted official first action.

High Performance Liquid Chromatographic Determination of Carbaryl Insecticide in Formulations

1980 ◽  
Vol 63 (3) ◽  
pp. 650-652
Author(s):  
William H Mcdermott
Keyword(s):  
High Performance ◽  
Methylene Chloride ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
High Performance Liquid Chromatographic ◽  
Modified Silica Gel ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A high performance liquid chromatographic method for carbaryl in formulations has been developed and used to assay 3 formulations in a 10-day repeatability study. The method uses a cyano modified silica gel column packing and a mobile phase of heptane-methylene chloride-isopropanol-methanol (60+35+4.8+0.2). The coefficients of variation for 2 wettable powders and one aqueous flowable formulation were 0.61, 0.62, and 0.75%, respectively. It is recommended that a collaborative study be conducted on this method.

Gas-Liquid Chromatographic Determination of Tetradif on Technical and Formulations: Collaborative Study

1981 ◽  
Vol 64 (4) ◽  
pp. 829-832
Author(s):  
Bram Van Rossum ◽  
Albertus Martijn ◽  
James E Launer ◽  
◽  
E C Calamita ◽  
...  
Keyword(s):  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Flame Ionization ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

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.

Liquid Chromatographic Determination of Triadimefon in Technical and Formulated Products: Collaborative Study

1985 ◽  
Vol 68 (3) ◽  
pp. 586-589
Author(s):  
Stephen C Slahck
Keyword(s):  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Normal Phase ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Technical Products

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.

Liquid Chromatographic Determination of Colchicine in Pharmaceuticals: Collaborative Study

1985 ◽  
Vol 68 (5) ◽  
pp. 1051-1055
Author(s):  
Richard D Thompson
Keyword(s):  
Collaborative Study ◽  
Chromatographic Determination ◽  
Pharmaceutical Dosage Forms ◽  
Coefficients Of Variation ◽  
Drug Sample ◽  
Buffer Mixture ◽  
Liquid Chromatographic Determination ◽  
Bulk Drug ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method for the determination of colchicine in pharmaceutical dosage forms and the bulk drug was evaluated in an interlaboratory study which included 13 participating laboratories. The method involves extraction (or dissolution) of the active ingredient with methanol-water (1 + 1), followed by filtration of the extract and reverse phase LC using an octy lsilane bonded phase column and UV detection at 254 nm. The mobile phase consists of a methanolphosphate buffer mixture (pH = 5.5). Three commercial tablet formulations (0.5-0.6 mg colchicine/tablet), 1 synthetic injectable preparation (0.510 mg colchicine/mL), and 1 bulk drug sample were assayed in duplicate by the proposed method. The reproducibility and repeatability standard deviations based on nonpooled results for each sample ranged from 0.0062 mg/mL to 0.0147 mg/tablet and from 0.0037 mg/ mL to 0.0127 mg/tablet, respectively; the corresponding coefficients of variation ranged from 1.21 to 2.54% and from 0.73 to 2.19%, respectively. The mean recovery from the synthetic injectable formulation was 100.0%. The method has been adopted official first action

Liquid Chromatographic Determination of Bendiocarb in Technical Materials and Wettable Powder Formulations: Collaborative Study

1986 ◽  
Vol 69 (5) ◽  
pp. 908-911
Author(s):  
Peter L Carter ◽  
Keith C Overton ◽  
◽  
P G Baker ◽  
O O Bennett ◽  
...  
Keyword(s):  
Statistical Data ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Liquid Chromatograph ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

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.

High Pressure Liquid Chromatographic Determination of Oxazepam Dosage Forms: Collaborative Study

1983 ◽  
Vol 66 (4) ◽  
pp. 864-866
Author(s):  
Eileen S Bargo ◽  
◽  
E Aranda ◽  
C Bonnin ◽  
S Hauser ◽  
...  
Keyword(s):  
High Pressure ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Reverse Phase ◽  
High Pressure Liquid Chromatographic ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A reverse phase high pressure liquid chromatographic method for the determination of oxazepam in tablets and capsules was collaboratively studied by 9 laboratories. Collaborators were supplied with 6 samples that included synthetic and commercial formulations. Tablet and capsule composites are diluted with methanol and filtered. Oxazepam is determined at 254 nm by using a C18 column. Mean recoveries of oxazepam from synthetic tablet and capsule formulations were 97.2 and 99.0%, respectively. Mean coefficients of variation for tablets and capsules ranged from 1.85 to 2.86%. The method has been adopted official first action.

Gas Chromatographic Determination of Fensulfothion in Formulations: Collaborative Study

1986 ◽  
Vol 69 (3) ◽  
pp. 488-490
Author(s):  
William R Betker ◽  
◽  
E W Balcer ◽  
O O Bennett ◽  
W R Coffman ◽  
...  
Keyword(s):  
Chromatographic Method ◽  
Methylene Chloride ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Gas Chromatograph ◽  
Technical Product ◽  
Coefficients Of Variation ◽  
Gas Chromatographic Method

Abstract A collaborative study was conducted on a gas chromatographic method for determination of fensulfothion. Eleven laboratories analyzed 2 technical and two 6 lb/U.S. gal. spray concentrate samples. In the analysis, samples are dissolved in methylene chloride which contains 4-chlorophenyl sulfoxide as an internal standard, and solutions are injected into a gas chromatograph equipped with an OV-330 column. Withinlaboratory repeatability was 0.79% for technical product and 0.37% for the spray concentrate samples, with coefficients of variation of 0.88 and 0.58%, respectively. Among-laboratories reproducibility was 0.81% for technical product and 0.53% for the spray concentrate, with coefficients of variation of 0.91 and 0.84%, respectively. The method has been adopted official first action.

Liquid Chromatographic Determination of Aminocarb in Technical and Formulated Products: Collaborative Study

1985 ◽  
Vol 68 (3) ◽  
pp. 567-569 ◽  
Author(s):  
Stephen C Slahck
Keyword(s):  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Reverse Phase ◽  
Reverse Phase Chromatography ◽  
Coefficients Of Variation ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract An LC method for determination of aminocarb (Matacil™) in aminocarb technical and formulated products has been developed and subjected to a collaborative study with 10 participating collaborators. Formulations are extracted with tetrahydrofuran-buffer (60 + 40) and analyzed by reverse phase chromatography, with n-butyrophenone as internal standard. Collaborators were furnished with standards and samples of technical and 180 oil flowable products for analysis. Coefficients of variation obtained on these samples were 0.72 and 1.7%, respectively. The method has been adopted official first action.

Sign in / Sign up

Export Citation Format

Share Document