Gradient Multipeak Liquid Chromatographic Method for Determination of Ardacin in Bulk Chemical and Premix Formulations

1995 ◽  
Vol 78 (2) ◽  
pp. 289-293
Author(s):  
Hafez Abdel-Kader ◽  
Myriam M Kobylkevich ◽  
Larry S Wigman ◽  
Govind K Menon

Abstract A liquid chromatographic (LC) method was developed for the determination of ardacin in bulk chemical (78 to 100%, w/w anhydrous) and premix formulations (3.3 to 26.4%, w/w). The method is based on reversed-phase LC resolution of ardacin components and detection by UV absorbance at 220 nm. Ardacin has 10 components, and each component can be quantitated separately. Total ardacin is determined by summing the areas of the 10 component peaks. Calculations are performed using an external standard approach. The method is linear for ardacin at 50 to 150 μ/mL. The method accuracy for a typical bulk chemical is ± 1.5%, w/w (relative standard deviation [RSD], 1.6%), and recovery from a typical pilot scale premix is 99.9% (RSD, 3.4%). The method is useful for monitoring stability during storage.

1994 ◽  
Vol 77 (6) ◽  
pp. 1341-1346
Author(s):  
Hafez Abdel-Kader ◽  
Sylvia V Fagan ◽  
Govtnd K Menon ◽  
Larry S Wigman ◽  
Frederic Chapin

Abstract A rapid and sensitive 2-peak liquid chromatographic (LC) method is described for extracting and quantitating ardacin in premix, supplement, and animal feed formulations. Ardacin is extracted from the formulations and analyzed after dilution or cleanup by reversed-phase LC with UV detection at 220 nm. The method correlates well with a more information-rich gradient multipeak LC method. Recoveries for premix formulations ranged from 96.8% (relative standard deviation [RSD], 0.8%) to 103.7% (RSD, 1.3%) for laboratory samples spiked at levels ranging from 1.6 to 39.6% ardacin. Recoveries for protein supplement mash formulations ranged from 98.7% of claim (RSD, 4.1%) to 106.0% of claim (RSD, 7.7%) at ardacin levels ranging from 37.5 to 600 mg/lb. Recoveries for cattle feed ranged from 90.0% of claim (RSD, 11.9%) to 105.6% of claim (RSD, 2.7%) at ardacin levels ranging from 4 to 30 g/ton.


2001 ◽  
Vol 84 (3) ◽  
pp. 676-683 ◽  
Author(s):  
Natividad Ramos-Martos ◽  
Francisco Aguirre-Gómez ◽  
Antonio Molina-Díaz ◽  
Luis F Capitán-Vallvey

Abstract This paper describes a rapid reversed-phase liquid chromatographic method, with UV detection, for the simultaneous determination of acetylsalicylic acid, caffeine, codeine, paracetamol, pyridoxine, and thiamine in pharmaceutical preparations. A reversed-phase C18 Nucleosil column is used. The mobile phase consists of 2 successive eluants: water (5 min) and acetonitrile–water (75 + 25, v/v; 9 min), both adjusted to pH 2.1 with phosphoric acid. Before determination acetylsalicylic acid is completely converted to salicylic acid by alkaline hydrolysis. Salicylic acid, caffeine, paracetamol, pyridoxine, and thiamine are all detected at 285 nm, whereas codeine is detected at 240 nm. Calibration curves were linear for salicylic acid, caffeine, paracetamol, and pyridoxine in the range of 50–500 mg/L, and for codeine and thiamine in the range of 50–1000 mg/L. The method was applied to the analysis of 13 fortified commercial pharmaceutical preparations. Recoveries ranged from 92.6 to 105.5%, with relative standard deviations of 1.1–5.8%.


2005 ◽  
Vol 88 (6) ◽  
pp. 1677-1683 ◽  
Author(s):  
María A Moyano ◽  
María A Rosasco ◽  
María T Pizzorno ◽  
Adriana I Segall

Abstract An accurate, simple, reproducible, and sensible liquid chromatographic method was developed and validated for the determination of chlorpheniramine maleate and dexamethasone in a tablet formulation. The analysis was performed at room temperature on a reversed-phase C18 column with UV detection at 254 nm. The mobile phase consisted of 7.5 mM monobasic potassium phosphate in methanol–water (62.5 + 37.5) at a constant flow rate of 1 mL/min. The method was validated in terms of linearity, precision, accuracy, and specificity by forced decomposition of chlorpheniramine maleate and dexamethasone initiated by using acid, base, water, hydrogen peroxide, heat, and light. The response was linear in the ranges of 0.04–0.12 and 0.006–0.016 mg/mL for chlorpheniramine maleate (r2 = 0.9999) and dexamethasone (r2 = 0.9994), respectively. The relative standard deviation values for intra- and interday precision studies were 2.39 and 2.02, respectively, for chlorpheniramine maleate and 2.39 and 1.25, respectively, for dexamethasone. Recoveries ranged from 95.07 to 101.95% for chlorpheniramine maleate and from 97.75 to 102.10% for dexamethasone.


2008 ◽  
Vol 91 (6) ◽  
pp. 1271-1277 ◽  
Author(s):  
M Nurul Islam ◽  
Hye Hyun Yoo ◽  
Jun Lee ◽  
Joo Won Nam ◽  
Eun Kyoung Seo ◽  
...  

Abstract The rhizomes of Anemarrhena asphodeloides Bunge (Liliaceae) are prescribed as crude drugs in herbal medication for the treatment of various diseases such as diabetes, inflammation, and platelet aggregation inhibition. A simple, sensitive, and precise reversed-phase liquid chromatographic method was developed to study the quantitative determination of 5 bioactive compounds from these rhizomes, namely, neomangiferin, mangiferin, isomangiferin, nyasol, and methylnyasol. Chromatographic analysis was performed on Capcell Pak C18 column (150 4.6 mm, 3 m) with a mobile phase consisting of acetonitrile, methanol, and 0.1 formic acid at a flow rate of 1.00 mL/min. Quantitation was performed using a UV-visible detector at 260 nm. The method for the determination of reported medicinal agents was accurate and reproducible. Excellent linear behavior was observed over the investigated concentration range of 2.5100.0 g/mL for neomangiferin; 1.560.0 g/mL for mangiferin; 0.520.0 g/mL for nyasol; and 0.220.0 g/mL for methylnyasol; correlation coefficient >0.99. The intraday and interday precision over the concentration range of compounds was <6.6 (relative standard deviation) and accuracy was between 94.9 and 109.3. This method can be successfully applied for the analysis of medicinal compounds from the ethanolic extract of A. asphodeloides Bunge.


1993 ◽  
Vol 76 (2) ◽  
pp. 414-417 ◽  
Author(s):  
Henry S Kim ◽  
Gerald Angyal

Abstract A reversed-phase liquid chromatographic (LC) method coupled with precolumn derivatization of L-tryptophan with phenylisothiocyanate was compared to the AOAC microbiological method for determining L-tryptophan in tablets and capsules. For the microbiological method, the concentrations of L-tryptophan were 4-8% lower in autoclaved test samples (hot method) than in test samples that were not autoclaved (cold method). When L-tryptophan values obtained by the LC method were compared to those obtained by the cold microbiological method, no significant differences were observed (P > 0.05). The mean relative standard deviations were 2.9% for the LC method and 1.6% for the cold microbiological method. The mean recoveries of standard L-tryptophan added before analysis were 99% for the LC method and 101 % for the cold microbiological method. These results demonstrate that both methods are reliable for determining free L-tryptophan contained in tablets and capsules. However, the LC method has the advantages of using a smaller test portion and having a shorter analysis time.


2013 ◽  
Vol 9 (2) ◽  
pp. 26-29 ◽  
Author(s):  
AK Hemanth Kumar ◽  
V Sudha ◽  
Geetha Ramachandran

A high performance liquid chromatographic method for determination of rifabutin in human plasma was  developed. The method involved deproteinisation of the sample with acetonitrile and analysis of the  supernatant using a reversed-phase C18 column (250mm) and UV detection at a wavelength of 265nm.  The assay was specific for rifabutin and linear from 0.025 to 10.0μg/ml. The relative standard deviation  of intra- and inter-day assays was lower than 10%. The method was able to remove interfering materials  in plasma, yielding an average recovery of rifabutin from plasma of 101%. Due to its simplicity, the assay  can be used for pharmacokinetic studies of rifabutin. SAARC Journal of Tuberculosis, Lung Diseases & HIV/AIDS; 2012; IX(2) 26-29 DOI: http://dx.doi.org/10.3126/saarctb.v9i2.7975


1996 ◽  
Vol 79 (2) ◽  
pp. 451-455 ◽  
Author(s):  
Allan R Brause ◽  
Mary W Trucksess ◽  
Frederick S Thomas ◽  
Samuel W Page ◽  
J Burke ◽  
...  

Abstract An AOAC International-International Union of Pure and Applied Chemistry-International Fruit Juice Union (AOAC-IUPAC-IFJU) collaborative study was conducted to evaluate a liquid chromatographic (LC) procedure for determination of patulin in apple juice. Patulin is a mold metabolite found naturally in rotting apples. Patulin is extracted with ethyl acetate, treated with sodium carbonate solution, and determined by reversed-phase LC with UV detection at 254 or 276 nm. Water, water-tetrahydrofuran, or water-acetonitrile was used as mobile phase. Levels determined in spiked test samples were 20, 50,100, and 200 μg/L. A test sample naturally contaminated at 31 μg/L was also included. Twenty-two collaborators in 10 countries analyzed 12 test samples of apple juice. Recoveries averaged 96%, with a range of 91-108%. Repeatability relative standard deviations (RSDr) ranged from 10.9 to 53.8%. The reproducibility relative standard deviation (RSDR) ranged from 15.1 to 68.8%. The LC method for determination of patulin in apple juice has been adopted first action by AOAC INTERNATIONAL.


1997 ◽  
Vol 80 (3) ◽  
pp. 549-554 ◽  
Author(s):  
Karl-Erik Hellenás ◽  
Carina Branzell ◽  
H Poutanen ◽  
T Suortti ◽  
R Kaario ◽  
...  

Abstract Twelve laboratories participated in a collaborative study to evaluate precision parameters of a liquid chromatographic method for analysis of the glycoalkaloids α-solanine and α-chaconine in potato tubers. Samples consisted of frozen potato tuber homogenates distributed as 3 blind duplicates and 3 split-level pairs. The analytical method included aqueous extraction, workup on disposable solidphase extraction cartridges, and reversed-phase chromatography with photometric detection at 202 nm. Results for α-solanine and α-chaconine were received from 10 and 9 laboratories, respectively. Relative standard deviations for reproducibilo ity for α-solanine and α-chaconine were similar, ranging from 8 to 13% in the applied concentration range of 12 to 260 mg/kg fresh weight.


2003 ◽  
Vol 86 (3) ◽  
pp. 510-514 ◽  
Author(s):  
Jeffery M van de Riet ◽  
Ross A Potter ◽  
Melissa Christie-Fougere ◽  
B Garth Burns

Abstract A liquid chromatographic (LC)/mass spectrometric (MS) method was developed for determining the residues of chloramphenicol, thiamphenicol, florfenicol, and florfenicol amine in a number of aquatic species. The phenicols are extracted with acetone, the extracts are partitioned with dichloromethane, the aqueous layer is removed, and the organic layer is evaporated to dryness. The residue is dissolved in dilute acid and defatted with hexane, and the aqueous layer is prepared for analysis by LC. The phenicols are determined by reversed-phase LC by using a Hypersil C18-BD column with a water–acetonitrile gradient and MS detection using selectedion recording. Calibration curves were linear for all analytes between 0.015 and 0.425 ng injected. The relative standard deviations for measurements by the proposed method were <10% for all of the analytes studied, with re-coveries ranging from 71% for florfenicol amine to 107% for florfenicol in salmon tissue spiked at the 2 ng/g level. Detection limits of 0.1 ng/g for florfenicol and chloramphenicol, 0.3 ng/g for thiamphenicol, and 1.0 ng/g for florfenicol amine are easily obtainable. The operational errors, interferences, and recoveries for spiked samples compare favorably with those obtained by established LC methodology. The proposed method is simple, rapid, and specific for monitoring residues of chloramphenicol, thiamphenicol, florfenicol, and florfenicol amine in a number of aquatic species.


1992 ◽  
Vol 75 (3) ◽  
pp. 379-383 ◽  
Author(s):  
Arthur Caputi ◽  
Eric Christensen ◽  
Nancy Biedenweg ◽  
Susan Miller

Abstract An Ion-exchange liquid chromatographic method for the determination of glycerol in wine, white grape juice, and pink grape juice was collaboratively studied by 8 laboratories. Eight wine types and 12 juice samples were provided to each collaborator. Using a strong cation column, blind duplicates and standards were analyzed by an external standard method. Separate statistical evaluations were run on wine, white grape juice, and pink grape juice data. The averages of the relative standard deviations for repeatability, excluding outlying results, were 1.25% for the wine samples, 7.32% for the white grape juice samples, and 8.63% for the pink grape juice samples. The averages of the relative standard deviations for reproducibility, excluding outlying results, were 2.79% for the wine samples, 16.97% for the white grape juice samples, and 19.10% for the pink grape juice samples. The method has been adopted first action by AOAC International.


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