Collaborative Study of the Ion-Pair Column Partition Method for the Determination of Phenylephrine.HC1 in Drug Formulations

1970 ◽  
Vol 53 (1) ◽  
pp. 120-122
Author(s):  
Michel Margosis
Keyword(s):  
Collaborative Study ◽  
Colorimetric Method ◽  
Ion Pair ◽  
Confidence Limits ◽  
Drug Formulations ◽  
Three Solutions ◽  
The Mean ◽  
Partition Method ◽  
Collaborative Evaluation

Abstract Three solutions containing varying amounts of phenylephrine.HC1 were subjected to a collaborative evaluation of the ion-pair column partition method of Levine and Doyle. Results submitted by 20 collaborators were evaluated statistically. Recoveries averaged 99.0, 100.8, and 103.5% with 95% confidence limits of the mean of ±0.71, ±0.53, and ±0.85%, respectively. The method is recommended for adoption as official first action. The colorimetric method approved last year is recommended for adoption as official final action.

Colorimetric and Ion-Pair Column Partition Determination of Phenylephrine in Drug Formula

1969 ◽  
Vol 52 (3) ◽  
pp. 500-506
Author(s):  
Michel Margosis
Keyword(s):  
Confidence Limit ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Ion Pair ◽  
Confidence Limits ◽  
Commercial Products ◽  
Partition Method ◽  
Collaborative Evaluation ◽  
Colorimetric Reaction

Abstract The Emerson 4-aminoantipyrine colorimetric reaction as modified by Hiskey and Levin was applied to a number of commercial products containing antibiotics. Acetaminophen and tetracycline were found to interfere. Four different solutions containing varying known amounts of phenylephrine were submitted to a collaborative evaluation of the Koshy and Mitchner modification of the Emerson reaction, and to the ion-pair column partition method of Levine and Doyle. The results were evaluated statistically. The colorimetric method showed average recoveries of 99.7% for solution 1, 96.1% for solution 2, and 100.7% for solution 3, with a 95% confidence limit of ±1.4, 2.0, and 3.0%, respectively. Average recoveries by the ion-pair column partition method were 84–101% with 95% confidence limits ranging between 10 and 22%. The colorimetric reaction of Emerson as modified by Koshy and Mitchner is recommended for adoption as official first action, but collaborative study of the ion-pair column partition method of Levine and Doyle should be repeated.

Collaborative Study of the Nonaqueous Copper Colorimetric and Silver Titrimetric Methods for the Determination of Malathion in Technical Grade Malathion and in Malathion Formulation

1973 ◽  
Vol 56 (3) ◽  
pp. 579-585
Author(s):  
Richard S Wayne
Keyword(s):  
Excellent Agreement ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Sample Type ◽  
Technical Grade ◽  
Coefficients Of Variation ◽  
The Mean

Abstract The nonaqueous copper colorimetric and the silver titrimetric methods for the determination of malathion were studied collaboratively. The study involved wettable powders, emulsifiable concentrates, dusts, and the technical grade product. The mean of all of the results indicates that both procedures will give comparable values for each sample type used in the study. Agreement between replicates in individual laboratories was excellent. Agreement between laboratories was satisfactory; coefficients of variation ranged from 1.3 to 4.8% for the samples studied. The 2 methods offer improved reliability and ease of operation when compared to the official first action colorimetric method, 6.265–6.269. The methods have been adopted as official first action.

Automated Colorimetric Determination of Phenylephrine Hydrochloride in Drug Formulations. II. Collaborative Study

1971 ◽  
Vol 54 (3) ◽  
pp. 600-602
Author(s):  
Michel Margosis
Keyword(s):  
Coefficient Of Variation ◽  
Statistical Evaluation ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Colorimetric Determination ◽  
Good Recovery ◽  
Drug Formulations ◽  
Phenylephrine Hydrochloride ◽  
Automated Method

Abstract The automated colorimetric method designed by Lane for the analysis of phenylephrine HCl in drug formulations has been submitted to a collaborative study. Five samples, including 2 with known interferences, were sent to 9 collaborators. The results were subjected to statistical evaluation. These show good recovery and a maximum interlaboratory coefficient of variation of 4.5%. The automated method as evaluated in this study has been adopted as official first action.

Collaborative Study of the Determination of Ammonia as an Index of Decomposition in Crabmeat

1973 ◽  
Vol 56 (3) ◽  
pp. 598-601 ◽  
Author(s):  
Kurt Steinbrecher
Keyword(s):  
Statistical Analysis ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Ammonia Content ◽  
Mean Values ◽  
Bromine Water ◽  
Class 1 ◽  
Different Populations ◽  
The Mean

Abstract A colorimetric method for determining the ammonia content in crabmeat in various stages of decomposition was studied collaboratively. The method involves the color reaction between ammonia, thymol, and alkaline bromine water. The mean values for organoleptic Class 1, Class 2, and Class 3 of decomposition were found to be 281, 568, and 1376 μg NH3/g crabmeat, respectively. By statistical analysis these means were found to be significantly different from each other, and were found to arise from different populations. Useful cut-off points can be selected to separate the classes. The method has been adopted as official first action.

Colorimetric Determination of Hydroxyproline as Measure of Collagen Content in Meat and Meat Products: NMKL Collaborative Study

1990 ◽  
Vol 73 (1) ◽  
pp. 54-57 ◽  
Author(s):  
Kurt Kolar
Keyword(s):  
Collaborative Study ◽  
Colorimetric Method ◽  
Meat Products ◽  
Acid Oxidation ◽  
Colorimetric Determination ◽  
Mean Values ◽  
Collaborative Studies ◽  
Freeze Dried ◽  
Analytical Result

Abstract A colorimetric method for the determination of hydroxyproline as a measure of collagen in meat and meat products has been collaboratively studied in 18 laboratories. The method includes hydrolysis with sulfuric acid, oxidation with chloramine- T, and formation of a reddish purple complex with 4- dimethylaminobenzaldehyde. Five frozen and 3 freeze-dried samples were tested, ranging in content from 0.11 to 0.88% and from 0.39 to 4.0% hydroxyproline, respectively. The mean values of 2 identical samples were 0.245 and 0.251 %. The average recovery from a spiked sample was 96.1 %. The hydroxyproline content of a known sample (a mixture of 2 samples in the ratio 5:2) was calculated to 1.42%, which agrees well with the analytical result, 1.40%. In comparison with other collaborative studies, based on the ISO analytical method, the repeatability and reproducibility of this method agree well with the other results. This method was accepted as an official NMKL method by all national Committees, and has been adopted official first action by AOAC as an NMKLAOAC method.

Collaborative Study Using a ZDBT Colorimetric Method for the Determination of Copper in Alcoholic Products

1967 ◽  
Vol 50 (2) ◽  
pp. 334-338
Author(s):  
Duane H Strunk ◽  
A A Andreasen
Keyword(s):  
Sulfuric Acid ◽  
Carbon Tetrachloride ◽  
Collaborative Study ◽  
Colorimetric Method ◽  
Good Precision ◽  
Determination Of Copper

Abstract Results are given on a collaborative study in which a zinc dibenzyldithiocarbamate (ZDBT) colorimetric method is used to measure copper in alcoholic products such as high wine, spirits, gin, whisky, brandy, rum, and wine. In this method, the sample is made ca 0.SN with sulfuric acid, and carbon tetrachloride containing 0.2% ZDBT is added. The colored copper-ZDBT complex is extracted in the carbon tetrachloride and measured at 438 mμ against a similar carbon tetrachloride extract of a blank. Data show good precision, and it is recommended that the ZDBT method be adopted as official, first action.

Determination of Maleic Hydrazide Residues in Tobacco and Vegetables

1973 ◽  
Vol 56 (5) ◽  
pp. 1164-1172
Author(s):  
Milan Ihnat ◽  
Robert J Westerby ◽  
Israel Hoffman
Keyword(s):  
Standard Deviation ◽  
Present Method ◽  
Maleic Hydrazide ◽  
Collaborative Study ◽  
Official Method ◽  
Sample Weight ◽  
Relative Standard ◽  
The Mean ◽  
Pipe Tobacco

Abstract The distillation-spectrophotometric method of Hoffman for determining maleic hydrazide has been modified to include a double distillation and was applied to the determination of 1–30 ppm maleic hydrazide residues in tobacco and vegetables. Recoveries of 1–23 μg added maleic hydrazide were independent of weight of maleic hydrazide, but did depend on sample and sample weight. The following recoveries were obtained from 0.5 g sample: pipe tobacco, 84%; commercially dehydrated potato, 83%; cigar tobacco, 81%; dried potato, 76%; fluecured tobacco, 73%; dried carrot, 71%. In the absence of sample, the recovery was 82%. When appropriate standard curves were used, maleic hydrazide levels determined in tobacco samples were essentially independent of sample weight in the range 0.1–3 g. The mean relative standard deviation for a variety of field-treated and fortified tobacco samples containing 1–28 ppm maleic hydrazide was 3%. The precision and sensitivity of this procedure seem to be substantial improvements over official method 29.111–29.117. It is recommended that the present method be subjected to a collaborative study.

Liquid Chromatographic Determination of Diazepam in Tablets: Collaborative Study

1985 ◽  
Vol 68 (3) ◽  
pp. 545-546
Author(s):  
Michael Tsougros
Keyword(s):  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Reverse Phase ◽  
Photometric Detection ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
The Mean ◽  
Liquid Chromatographic

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.

Analysis of Fat-Soluble Vitamins. XX. Determination of Vitamin D in Multivitamin Preparations. Second Collaborative Study

1978 ◽  
Vol 61 (3) ◽  
pp. 735-745
Author(s):  
Ellen J De Vries ◽  
Frits J Mulder ◽  
Ben Borsje
Keyword(s):  
Vitamin D ◽  
Vitamin A ◽  
Test Data ◽  
Vitamin D3 ◽  
Collaborative Study ◽  
Three Samples ◽  
The Mean ◽  
Fat Soluble Vitamins

Abstract The official first action method for determining vitamin D in multivitamin preparations was modified. The method was collaboratively studied by 7 laboratories, using 6 preparations in oil. The preparations consisted of vitamin D at various levels and at various ratios (in w/w) to vitamin A. Three samples contained cholecalciferol and 3 samples contained vitamin D3 from vitamin D3 resin. After outliers were eliminated by the Dixon test, data were analyzed and averages were compared with amounts of vitamin D known to be in each sample. For samples with vitamin D: vitamin A ratios of 1:0.5, 1:5, and 1:10, the mean vitamin D recoveries were 98.8, 94.6, and 90.7%, respectively. The method has been adopted as official final action.

Colorimetric Method for Rapid Determination of Serum Arginase

1967 ◽  
Vol 13 (10) ◽  
pp. 900-908 ◽  
Author(s):  
Brigitta Mellerup
Keyword(s):  
Rapid Determination ◽  
Colorimetric Method ◽  
Normal Range ◽  
Clinical Routine ◽  
Mean Values ◽  
Enzymatic Formation ◽  
Significant Difference ◽  
The Mean ◽  
Normal Men

Abstract A method for the determination of serum arginase is given which combines the enzymatic formation of urea with the sensitive method of Coulombe (1) for measuring this substance. This procedure allows more accurate determinations in the normal range than do previous methods described and is convenient for clinical routine. Significant difference is found between the mean values of normal men and women, 3.9 units/L. for the former and 2.9 units/L. for the latter.

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