Collaborative Study of a Fluorometric and Thin Layer Chromatographic Determination of Aminacrine and Its Salts in Drug Preparations

1967 ◽  
Vol 50 (3) ◽  
pp. 680-682
Author(s):  
Laura A Roberts

Abstract Eight collaborators studied a fluoromelric and thin layer chromatographic method for aminacrine and its salts in powder and cream drug preparations. Recovery of aminacrine.HCI by fluorometer in both preparations averaged 100% for powder and 102% for cream. The mean concentration of aminacrine.HCI found in the powder was 0.108% with a standard deviation of ± 0.001%. The mean concentration of aminacrine found in the cream was 0.191% with a standard deviation of ± 0.003%. Seven of the 8 collaborators successfully used thin layer chromatography to identify the aminacrine in both sample forms supplied. The assay method for aminacrine and its salts in drug preparations is recommended for adoption as official, first action

1986 ◽  
Vol 69 (1) ◽  
pp. 37-40 ◽  
Author(s):  
Robert M Eppley ◽  
Mary W Trucksess ◽  
Stanley Nesheim ◽  
Charles W Thorpe ◽  
Albert E Pohland ◽  
...  

Abstract A collaborative study of a rapid method for the determination of deoxynivalenol (DON) in winter wheat was successfully completed. The method involves sample extraction with acetonitrile-water (84 + 16), cleanup using a disposable column of charcoal, Celite, and alumina, and detection by thin layer chromatography after spraying with an aluminum chloride solution. Each of the 15 collaborators analyzed 12 samples, 2 of which were naturally contaminated, and 10 to which DON was added, in duplicate, at levels of 0,50,100,300, and 1000 ng/ g. Average recoveries of DON ranged from 78 to 96% with repeatabilities of 30-64% and reproducibilities of 33-87%. The results of the study show that false positives were not a problem and that all of the analysts could detect DON at the 300 ng/g level or higher. The method has been adopted official first action.


1987 ◽  
Vol 70 (5) ◽  
pp. 842-844
Author(s):  
Octave J Francis ◽  
George M Ware ◽  
Allen S Carman ◽  
Gary P Kirschenheuter ◽  
Shia S Kuan ◽  
...  

Abstract A collaborative study of a method for the determination of sterigmatocystin in cheese was conducted by 10 laboratories. The study included control samples and samples spiked at levels of 5, 10, and 25 ppb, in coded blind pairs. Recoveries were 60.0, 90.7, and 59.3%, outliers excluded, for the respective levels. The mean reproducibilities, outliers excluded, were 81.97, 17.13, and 52.77%, respectively. Mean repeatabilities, outliers excluded, were 77.66,17.13, and 46.40%, respectively. Results of this collaborative study indicate that the method, modified as described in this report, is applicable to the determination of sterigmatocystin in cheese at low levels (5-50 ppb) for the purpose of surveys. With regard to the difficulty with thinlayer chromatography in this study, it is recommended that a more satisfactory determinative step be developed. Recommendation for official first action status is deferred


1974 ◽  
Vol 57 (3) ◽  
pp. 621-625 ◽  
Author(s):  
Peter M Scott

Abstract Collaborators in 20 laboratories studied a method for the determination of patulin in apple juice. The collaborators mixed patulin solutions with the apple juice to obtain 9 spiked samples (of which 2 were blanks) and 1 practice sample. After column chromatography of the apple juice extract, patulin was estimated visually by thin layer chromatography, using 3-methyl-2-benzothiazolinone hydrazone.HCl as the spray reagent. Mean recoveries of patulin ranged from 69.8 to 98.3% for 3 contamination levels. The method has been adopted as official first action for the determination of patulin in apple juice.


1978 ◽  
Vol 61 (3) ◽  
pp. 569-573
Author(s):  
Stanley Nesheim ◽  
Mary W Trucksess

Abstract The thin layer chromatographic method of Trucksess et al. for aflatoxin Bx in eggs was collaboratively studied. Each collaborator analyzed 3 known practice samples and 9 unknown samples containing added aflatoxin Bx at 0, 0.05, 0.10, and 0.30 ng/g. For 9 collaborators, recoveries for the 3 positive levels were: 0–0.13 ng/g (average 98%, coefficient of variation (C.V.) 83%), 0.05-0.18 ng/g (average 102%, C.V. 36%), and 0.11-0.42 ng/g (average 93%, C.V. 31%), respectively. The method has been adopted as official first action.


1973 ◽  
Vol 56 (5) ◽  
pp. 1164-1172
Author(s):  
Milan Ihnat ◽  
Robert J Westerby ◽  
Israel Hoffman

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.


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.


1974 ◽  
Vol 57 (4) ◽  
pp. 961-962
Author(s):  
Sandra Bell

Abstract A thin layer chromatographic method is presented by which triethylrhodamine and other lower ethylated subsidiary colors are separated from D&C Red No. 19 and D&C Red No. 37. After removal from the plate, subsidiary dyes are extracted from silica gel C adsorbent and quantitated spectrophotometrically. Recoveries of 1, 2, and 5% of added triethylrhodamine ranged from 89 to 1 0 3% for D&C Red No. 19 and from 85 to 1 0 2% for D&C Red No. 37.


1985 ◽  
Vol 68 (5) ◽  
pp. 952-954
Author(s):  
Maria Luisa Serralheiro ◽  
Maria Lurdes Quinta

Abstract A method has been developed for the detection of aflatoxin Mi in milk. The toxin is extracted with chloroform, the extract is evaporated, and the residue is partitioned between carbon tetrachloride and an aqueous saline-methanol solution. The toxin is once again extracted with chloroform from the methanol solution and analyzed by thin layer chromatography. The limit of detection of Mi in powdered milk is 0.5 μg/ kg; recoveries of added Mj are about 83%. The limit of detection can be improved to 0.3 μg/kg if the plate is sprayed with an aqueous solution of H2S04 after development.


Author(s):  
Sumithra M

Objective: The objective of the study is simple, sensitive; eco-friendly reverse phase chromatographic method has been developed and validated for the quantitative determination of ofloxacin in bulk and marketed formulation. Method: The developed method was done using Hypersil silica C18 (250 mm × 4.6 mm, 5 μ particle size) as column and the mobile phase is containing water and methanol in the ratio of (10:90) vol/vol. The mobile phase pass at 1 ml/min flow rate and the eluted solution is measured at 270 nm using a PDA detector. Results: The assay method is linear from the concentration range of 5–30 μg/ml. The corelation coefficient is 0.9998. The mean percentage recovery for the developed method is found to be in the range of 98.4–100.6%. The developed method complies robustness studies. Conclusion: The validation of the developed method was done by as per the ICH guidelines. It obeys the linearity, accuracy, precision, and robustness studies. Validation parameters are within the limitations. The results of the developed process indicated the reverse phase chromatographic method is simple, accurate as well as precise, rapid and eco-friendly method for routine analysis of ofloxacin in bulk and its pharmaceutical dosage form.


1978 ◽  
Vol 61 (4) ◽  
pp. 903-905
Author(s):  
Joel J Thrasher ◽  
Annette Abadie

Abstract A collaborative study has been completed on an improved method for the detection and confirmation of uric acid from bird and insect excreta. The proposed method involves the lithium carbonate solubilization of the suspect excreta material, followed by butanol-methanol-water-acetic acid thin layer chromatography, and trisodium phosphate-phosphotungstic acid color development. The collaborative tests resulted in 100% detection of uric acid standard at the 50 ng level and 75% detection at the 20–25 ng level. No false positives were reported during tests of compounds similar to uric acid. The proposed method has been adopted official first action; the present official final action method, 44.161, will be retained for screening purposes.


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