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1.
A liquid chromatographic (LC) method is described for the determination of quinine, hydroquinine, sodium saccharin, and sodium benzoate in soft drinks. The method involves simple sample preparation, direct injection onto an octadecylsilane column, and elution with a methanol-acetonitrile-water-acetic acid (20 + 10 + 70 + 1) mobile phase. Eluted constituents are measured spectrophotometrically at 254 nm. The relationship between peak height and concentration was linear between 20 and 120 micrograms/mL for quinine. A relative standard deviation of 0.82% was obtained for commercial samples spiked with quinine, and the average recovery was 100.3%. The proposed procedure is accurate and rapid and can also detect hydroquinine (a natural contaminant of quinine), sodium saccharin, and sodium benzoate. Linear responses ranged from 0.45 to 20 micrograms/mL for hydroquinine, from 54.8 to 219 micrograms/mL for sodium saccharin, and from 10.1 to 145.1 micrograms/mL for sodium benzoate. The reproducibility of the LC method was evaluated with standard solutions of hydroquinine, sodium saccharin, and sodium benzoate, which produced relative standard deviations of 0.42, 0.46, and 1.13%, respectively. The average recoveries for sodium saccharin and sodium benzoate from spiked samples were 99.4 and 100.2%, respectively.  相似文献   

2.
An analytical method has been developed that can reliably measure the metabolic marker residue of lasalocid. The method monitors this marker residue in food samples to ensure that the total residue of toxicological concern is not being exceeded. Interlaboratory studies of the liquid chromatographic determinative procedure and the gas chromatographic/mass spectrometric confirmatory procedure for lasalocid sodium at the 0.7 ppm level and higher were successful.  相似文献   

3.
A simple and rapid liquid chromatographic method is described for the determination of propranolol hydrochloride in pharmaceutical preparations. The separation was achieved on a reverse-phase octylsilane (C8) column by using a mobile phase composed of a mixture of 0.5 g dodecyl sodium sulfate in 18 mL (0.15 M) H3PO4 plus 90 mL methanol, 90 mL acetonitrile, and 52 mL water. Detector response was linear for 0.03-3.1 mg/mL of propranolol. Recoveries from synthetic mixtures ranged from 99.6 to 101.7%. The results obtained by the proposed method were similar to those obtained by the USP XXI method.  相似文献   

4.
A gas-liquid chromatographic method is described for the simultaneous determination of sorbic acid and sodium benzoate in table sirup. The preservatives are extracted from acidified sirup with ethyl acetate and are analyzed on a gas chromatograph equipped with a flame ionization detector and a glass column (4 ft X 4 mm id) containing 9% SP-1200 and 2% H3PO4 on Chromosorb W (AW). Coefficients of variation for sorbic acid and sodium benzoate are 0.62 and 0.41%, respectively. Analysis time is less than 20 min, with recoveries exceeding 90%.  相似文献   

5.
A reverse phase liquid chromatographic method for the determination of saccharin in a soft drink and a juice was collaboratively studied in 8 laboratories. Collaborators were supplied with 3 samples of the soft drink and 3 samples of the juice containing sodium saccharin levels of 40-100 mg/L. Average recoveries of sodium saccharin were 95.3% for the soft drink and 98.0% for the juice. The reproducibility coefficients of variation were 16.9% for the soft drink and 10.4% for the juice. In addition, a mini-collaborative study was conducted for the determination of saccharin in 3 samples of sweets produced commercially. Five collaborators analyzed the samples, which contained saccharin at levels of 100-600 mg/kg according to the maker's specifications. Saccharin was extracted with water and ethanol and chromatographed using a modified liquid chromatographic method. The reproducibility coefficient of variation was 12.4% for the sweets.  相似文献   

6.
A reverse-phase liquid chromatographic method is described for the assay of penicillin V potassium in tablets and powders for oral solution. Under isocratic conditions, the combined use of an octadecylsilane column, with a mobile phase composed of acetonitrile-methanol-0.01M monobasic potassium phosphate (21 + 4 + 75, v/v), and photometric detection at 225 nm, separated penicillin V potassium from excipients, related compounds, and degradation products. Sulfadimethoxine was used as an internal standard. Detector responses were linearly related to concentrations of penicillin V over the range 25-225 micrograms/mL (r = 0.99997). Standard addition recoveries ranged from 98.8 to 99.9% (mean 99.5%, n = 8) for tablets and from 97.9 to 101.6% (mean 99.8%, n = 8) for powders for oral solution. The liquid chromatographic assay results were compared with those obtained by the official iodometric titration method. The proposed method is simple, selective, stability-indicating, and free from interference by excipients and degradation products.  相似文献   

7.
A rapid, simple, and reliable liquid chromatographic method has been developed for the simultaneous determination of nicotinamide (niacinamide), thiamine, riboflavin, riboflavin sodium phosphate, pyridoxine, caffeine, and sodium benzoate in commercial oral liquid tonics. The 7 components are separated on a reverse phase C18 column using a mobile phase of acetonitrile-0.01M potassium dihydrogen phosphate-triethylamine (8 + 91.5 + 0.5 v/v/v) containing 5mM sodium octanesulfonate and adjusted to pH 2.8 with phosphoric acid. Components are detected at 254 nm with attenuation 0.02 AUFS. Acetanilide is used as an internal standard. In addition to the 7 components mentioned, nicotinic acid (niacin), cyanocobalamin, and folic acid are also separated under the same conditions. Sample preparation involves only addition to internal standard solution and dilution with mobile phase and then filtration. Recoveries of the 7 components and cyanocobalamin from spiked preparations ranged from 97 to 104% with coefficients of variation of 0.9-4.2%.  相似文献   

8.
A sensitive and precise liquid chromatographic method has been developed for the determination of total niacin in beef, semolina, and cottage cheese. The samples are extracted with Ca(OH)2, cleaned up using C18 Sep-Pak cartridges, and chromatographed on a C18 column using a mobile phase consisting of 23% acetonitrile, 0.10% H3PO4, and 0.10% sodium dodecyl sulfate in water. Niacin is detected using an absorbance detector operating at 254 nm. This chromatographic system produces an unusually sharp peak for niacin, enabling a detection limit of approximately 0.05 mg/100 g. The mean recovery was 99.5% and the coefficients of variation for beef, semolina, and cottage cheese were 3.58, 1.02, and 10.0%, respectively.  相似文献   

9.
A simple liquid chromatographic procedure is described for determination of the preservative dehydroacetic acid (DHA) in wine. No cleanup procedure is necessary; the sample is injected onto an NH2 column without further pretreatment. The mobile phase is a 9 + 1 mixture of acetonitrile-sodium acetate buffer adjusted to pH 4 with acetic acid. Total run time is less than 10 min. Dehydroacetic acid is determined by using the absorbance at 307 nm; the detection limit is estimated to be 0.2 ppm. The method may also be suitable for detecting DHA in a variety of foodstuffs in low concentrations.  相似文献   

10.
A simple and rapid stability-indicating liquid chromatographic method is described for quantitative determination of 6 sympathomimetic drugs in various liquid and solid formulations. Analyses were carried out on a C18 reverse phase column using 0.01M 1-octanesulfonic acid, sodium salt in 0.2% acetic acid-methanol (70 + 30) as the mobile phase with photometric detection at 220 nm. Coefficients of variation for 5 consecutive injections of a mixed standards solution ranged from 0.62% for metaraminol to 1.40% for epinephrine. Standard recoveries ranged from 98.8% for metaraminol to 100.8% for epinephrine. The method was linear between 0.2 and 10 micrograms of drug injected and was used successfully to analyze 17 commercial products in a variety of dosage forms.  相似文献   

11.
Isolation and gas chromatographic determination of chlorsulfuron in milk   总被引：2，自引：0，他引：2  
A method for the isolation and gas chromatographic determination of chlorsulfuron in milk is presented. Blank or chlorsulfuron-spiked milk samples were blended into C-18 (octadecylsilyl derivatized silica, ODS) packing material. A column made from the C-18/milk matrix was washed with hexane after which chlorsulfuron was eluted with dichloromethane (DCM). The DCM eluate contained chlorsulfuron which was free from interfering co-extractants when analyzed by gas chromatography utilizing a nitrogen/phosphorus detector. Chlorsulfuron was found to undergo a thermally induced decomposition to give 2-amino-4-methoxy-6-methyl-1,3,5-triazine, which was detected and quantitated by this method. Standard curves for these analyses were linear (r = 0.992 +/- 0.004, n = 5), with an average percentage recovery of 91.6 +/- 10.8%, over the concentration range examined (62.5-2000 ng/mL). The inter- and intra-assay variabilities were 11.6 +/- 7.5% and 6.2%, respectively.  相似文献   

12.
A high pressure liquid chromatographic procedure is described for assay of toxins associated with paralytic shellfish poisoning (PSP). The method is applicable to saxitoxin, neosaxitoxin, gonyautoxins I through IV, and their sulfocarbamoyl derivatives. Toxins are separated on a bonded phase cyano column and detected by fluorescence following alkaline oxidation (NH+4 and periodic acid). The utility of the HPLC procedure for research and monitoring is discussed.  相似文献   

13.
A liquid chromatographic (LC) procedure is described for the assay of morphine sulfate in bulk drug material and injection solutions. The bulk drug and injection samples are prepared by direct dilution with LC mobile solvent. The average bulk drug purity (5 manufacturers) determined by the LC method was 99.9% with a difference of 0.1% from the average purity (anhydrous) found by the official USP XX procedure. The average LC recovery (19 studies) of morphine sulfate added to injection samples was 99.4% with a coefficient of variation (CV) of 1.14%. Morphine sulfate content was determined in triplicate for 53 injection samples (1-15 mg morphine sulfate/mL) formulated by 6 manufacturers, using the proposed LC procedure. Individual sample CV (n = 3) averaged 1.14%. The LC method is simple and specific for morphine sulfate. Major degradation products, preservatives, and some contaminants and related compounds are separated during LC.  相似文献   

14.
A simple and rapid method is presented for the liquid chromatographic assay of ascorbic acid, niacinamide, pyridoxine, thiamine, and riboflavin from a single chromatogram. Ion-pair chromatography with a reverse phase C18 cartridge in a radial compression system is used. Quantitation is excellent with a total analysis time of less than 20 min. A mobile phase of methanol-water (15 + 85) (0.005M heptanesulfonic acid) with 0.5% triethylamine at pH 3.6 and a flow rate of 2.0 mL/min gives the most satisfactory separation of the 5 water-soluble vitamins. By using 2 detectors in series set at different wavelengths and sensitivities, all 5 vitamins, with peak heights on scale, can be measured from a single injection; peak elution order is ascorbic acid, niacinamide, pyridoxine, thiamine, and riboflavin. Ascorbic acid is measured at 254 nm and the other vitamins, at 280 nm. The amount of amine modifier in the mobile phase is critical to the separation of niacinamide and pyridoxine. Recoveries of 5 water-soluble vitamins from spiked placebos were in the range of 98.2-102.0%. Confidence limits, +/- 3 SD, were in the range of 1.0-5.4%. Overall, the results obtained using the liquid chromatographic method show excellent agreement with manual methods and automated analysis.  相似文献   

15.
A simple and rapid liquid chromatographic method is described for the determination of barbaloin (aloin, 10-D-glucopyranosyl-1,8-dihydroxy-3-(hydroxymethyl)-9(10H)-anthraceno ne) in foods. Barbaloin is extracted with water from foods containing aloe and the extract is cleaned up on a disposable cartridge by using methanol-water (55 + 45) as eluant. The eluted barbaloin is separated by liquid chromatography on a YMC A-302 column with methanol-water (50 + 50) mobile phase, and detected at 293 nm. Recoveries of barbaloin added to foods at the levels of 0.05 and 0.50 mg/g were 94.4-100%. Assay results for commercial food samples indicated that the present method is applicable to a variety of foods supplemented with aloe.  相似文献   

16.
A simple and rapid gas-liquid chromatographic procedure, using a 6' times 1/4' glass column packed with 5% SE-30 on Chromosorb W (DMCS) and a flame ionization detector, is described. Grain baits containing strychnine alkaloid are ground, mixed, and extracted by shaking with chloroform containing an internal standard, 1,3,5-triphenylbenzene. Without further cleanup, extract filtrates are injected directly into a gas chromatograph. Peak height ratios are used for quantitation of strychnine. The analysis of commercial samples shows that the method compares well with a commonly employed ultraviolet spectrophotometric method; good precision, with recoveries ranging from 89.9 to 91.7%, is obtained in the analysis of prepared samples. The method is sensitive to 2 mug strychnine.  相似文献   

17.
A gas chromatographic method for determination of 2-hydroxymethyl-1-methyl-5-nitroimidazole (DMZOH), the hydroxy metabolite of dimetridazole, in swime muscle has been developed. The method uses cleanup steps similar to those of an earlier polarographic method. The present method is capable of quantitating levels as low as 2 ppb and detecting less than 1 ppb. Recoveries from 30 control tissues spiked at 1, 2, or 4 ppb averaged 80.4%. Performance of the method in incurred tissue was documented and limited data on the depletion of the metabolite in muscle were generated. The muscle of swine given 150 ppm dimetridazole in feed for 14 days contained less than 1 ppb DMZOH at 12 h withdrawal time.  相似文献   

18.
A simple and rapid liquid chromatographic method is described for the qualitative and quantitative determination of 5 coumarin anticoagulants in tablet composites and individual tablets. Analyses are carried out on a C18 reverse phase column using tetrahydrofuran-methanol-water-acetic acid (35 + 10 + 65 + 0.1) as mobile phase and photometric detection at 311 nm. The coefficients of variation for 10 consecutive injections of a mixed standards solution ranged from 0.28% for ethyl biscoumacetate to 0.78% for acenocoumarol. Standard recoveries were as follows: acenocoumarol, 99.3%; dicumarol, 99.6%; phenprocoumon, 101.6%; and warfarin sodium, 99.0%. The method was linear between 2 and 8 micrograms of drug injected. Assay results agreed favorably with those of the USP XX methods for dicumarol, phenprocoumon, and warfarin, and the NF XIV method for acenocoumarol. In addition, close correspondence was found with the results previously reported for the same drugs by a semiautomated spectrophotometric method. The content uniformity testing of individual 50 mg dicumarol tablets and 5 mg warfarin sodium tablets by the proposed method gave average (SD) values of 100.32% (0.64) and 101.00% (0.14), respectively, whereas these values were 101.60% (1.81) and 101.80% (0.18), respectively, by the method of USP XX.  相似文献   

19.
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.  相似文献   

20.
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 mL. 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.  相似文献   

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