Liquid Chromatographic Determination of Ochratoxin A in Coffee Beans and Coffee Products

1986 ◽  
Vol 69 (6) ◽  
pp. 960-964 ◽  
Author(s):  
Hisaya Terada ◽  
Haruo Tsubouchi ◽  
Katsuhiko Yamamoto ◽  
Kazuo Hisada ◽  
Yoshio Sakabe
Keyword(s):  
Ochratoxin A ◽  
Chromatographic Determination ◽  
Instant Coffee ◽  
Coffee Beans ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Better Than

Abstract A liquid chromatographic method for the determination of ochratoxin A in coffee beans (green and roast), instant coffee, and coffee drink is described. The sample is subjected to extraction with methanol-1% aqueous sodium bicarbonate (1 + 1) and C18 cartridge cleanup. The extract is chromatographed on a Nucleosil 5C18 column with a mobile solvent of acetonitrile-water-0.2M phosphate buffer pH 7.5 (50 + 47 + 3) containing 3mM cetyltrimethylammonium bromide as an ionpair reagent. Ochratoxin A is detected with a fluoromcter (excitation 365 nm, emission 450 nm). The sensitivity was increased 20-fold by using ion-pair resolution. The detection limits corresponded to 2 μg/kg for coffee beans, 5 μg/kg for instant coffee, and 0.2 μg/kg for coffee drink. The recoveries from coffee products were generally better than 80.7% and the relative standard deviations were 3.43-5.93%. The peak coinciding with ochratoxin A can be confirmed by treatment using alcohol (methanol, ethanol, or n-propanol) and H2S04.

Liquid Chromatographic Determination of Carminic Acid in Yogurt

1989 ◽  
Vol 72 (2) ◽  
pp. 231-234 ◽  
Author(s):  
Mercedes Jalón ◽  
Majesús Peńa ◽  
Julián C Rivas
Keyword(s):  
Chromatographic Determination ◽  
Carminic Acid ◽  
Reverse Phase ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Array Detection ◽  
Liquid Chromatographic Determination ◽  
Phase Liquid ◽  
Liquid Chromatographic

Abstract A reverse-phase liquid chromatographic method is described for the determination of carminic acid in yogurt. A C18 column is used with acetonitrile-1.19M formic acid (19 + 81) as mobile phase and diode array detection. Sample preparation includes deproteinization with papain and purification in a polyamide column. The relative standard deviation for repeated determinations of carminic acid in a commercial strawberry-flavored yogurt was 3.0%. Recoveries of carminic acid added to a natural-flavored yogurt ranged from 87.2 to 95.3% with a mean of 90.2%. The method permits measurement of amounts as low as 0.10 mg/kg.

Liquid Chromatographic Determination of Morphine Sulfate and Some Contaminants in Injections and Bulk Drug Material: Collaborative Study

1988 ◽  
Vol 71 (5) ◽  
pp. 1046-1048
Author(s):  
Ada C Bello ◽  
Rita K Jhangiani
Keyword(s):  
Collaborative Study ◽  
Chromatographic Determination ◽  
Morphine Sulfate ◽  
System Suitability ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Bulk Drug ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method for the assay of morphine sulfate and some preservatives and impurities in the bulk drug and in injections has been developed and collaboratively studied in 8 laboratories. Each collaborator analyzed 5 samples: 1 bulk drug, 3 different concentrations of injectable dosages, and 1 prepared mixture containing, in addition to morphine sulfate, phenol, 2-mercaptobenzothiazole, and pseudomorphine. The proposed method quantitates morphine sulfate and resolves the other components for identification using a Clg reverse-phase column with a mobile solvent containing 240 mL methanol, 720 mL 0.005M 1-heptanesulfonic acid Na salt, and 10 mL acetic acid. Samples are prepared by direct dilution with mobile solvent minus 1-heptanesulfonic acid. All collaborators met system suitability requirements and performed the analysis without difficulty. No outliers were found when data were analyzed by the Dixon, Grubbs, double Grubbs, and Cochran tests. Relative standard deviations between laboratories (RSDR) for duplicate determinations of morphine sulfate ranged from 1.4 to 2.1%. Mean morphine sulfate recoveries for the bulk drug and the prepared mixture were 100.8 and 100.4%, respectively. The method has been approved interim official first action.

scholarly journals Liquid Chromatographic Determination of the Glycoalkaloids α-Solanine and α-Chaconine in Potato Tubers: NMKL Interlaboratory Study

1997 ◽  
Vol 80 (3) ◽  
pp. 549-554 ◽  
Author(s):  
Karl-Erik Hellenás ◽  
Carina Branzell ◽  
H Poutanen ◽  
T Suortti ◽  
R Kaario ◽  
...  
Keyword(s):  
Collaborative Study ◽  
Chromatographic Determination ◽  
Reversed Phase ◽  
Potato Tubers ◽  
Photometric Detection ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

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.

Stability-Indicating Liquid Chromatographic Determination of Alpha-Ionone in Toothpaste

1988 ◽  
Vol 71 (1) ◽  
pp. 36-37
Author(s):  
Ramesh J Trivedi
Keyword(s):  
Standard Deviation ◽  
Chromatographic Method ◽  
Cost Effective ◽  
Chromatographic Determination ◽  
Average Recovery ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A simple, sensitive, and rapid liquid chromatographic method for quantitating α-ionone in toothpaste at levels of 20 ppm in the presence of large amounts of flavor has been developed. The method is accurate, precise, cost-effective, and specific for α-ionone. Average recovery of a laboratory-prepared sample was 99.0% with the relative standard deviation was 1.29% (n = 6).

Liquid Chromatographic Determination of Unbound and Acetone-Soluble Bound Gossypol in Cottonseed Meals and Mixed Feeds

1992 ◽  
Vol 75 (5) ◽  
pp. 815-823
Author(s):  
Nickos A Botsoglou
Keyword(s):  
Chromatographic Determination ◽  
Gradient Elution ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
On Line ◽  
Liquid Chromatographic Determination ◽  
Mixed Feeds ◽  
Liquid Chromatographic ◽  
Hydrolysis Of

Abstract A liquid chromatographic method has been developed for the determination of unbound and acetone- soluble bound gossypol in cottonseed meals and mixed feeds at levels of 0.5 ppm. The method involves extraction with aqueous acetone in the presence of ascorbic acid, hydrolysis of the "soluble bound" forms with hydrochloric acid, partitioning into chloroform, and chromatographic separation on a 10 µm C18 column by step gradient elution using a methanol-water mobile phase acidified with phosphoric acid. With minor modifications, the method permitted discriminate determination of unbound gossypol and acetone-soluble hydrophilic and lipophilic forms of bound gossypol. The gossypol peak was characterized by on-line spectral scanning and absorbance rationing. Overall relative standard deviation was 6.7% and overall recovery was 98.1 ± 3.3%. When the method was applied to several cottonseed meal samples, results were inconsistent with those obtained by the official American Oil Chemists' Society method for "free" gossypol determination.

Liquid Chromatographic Determination of Saccharin in Beverages and Desserts: Complementary Collaborative Study

1988 ◽  
Vol 71 (6) ◽  
pp. 1210-1212 ◽  
Author(s):  
Anna-Maija K SjÖberg
Keyword(s):  
Concentration Level ◽  
Soft Drink ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Food Control ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A complementary collaborative study was conducted on a liquid chromatographic method for determination of saccharin in accordance with the latest international recommendations. One industrial and 6 official food control laboratories analyzed 3 samples of a juice, a soft drink, and a dessert at concentration levels of 26-90 mg/L, 33-73 mg/L, and 56-147 mg/kg, respectively. Blind duplicates and a blank were supplied for each type of material at each concentration level. The beverage was chromatographed directly and the dessert was extracted with ethanol before chromatography. Average recoveries were 95-107%. The reproducibility relative standard deviations were 6.4-7.3% for the juice, 9.2-20.6% for the soft drink, and 13.4-16.2% for the dessert. The outlier percentage was 14.3%. The results were compared with those of an earlier collaborative study by Nordic laboratories and with general collaborative results obtained by AOAC

scholarly journals Liquid Chromatographic Determination of Scopolamine, Hyoscyamine, and Phenobarbital in Tablets

1997 ◽  
Vol 80 (2) ◽  
pp. 331-334 ◽  
Author(s):  
Susan Ting
Keyword(s):  
Mobile Phase ◽  
Chromatographic Determination ◽  
Reversed Phase ◽  
Scopolamine Hydrobromide ◽  
Acid Sodium Salt ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method using a reversed- phase C18 column and octanesulfonic acid sodium salt-methanol as the mobile phase was developed for the simultaneous determination of phenobarbi- tal, scopolamine, and hyoscyamine in tablets. The mixture of the 3 drugs was resolved in <8 min. Detector responses were linear for 10 μL injections of the following: scopolamine hydrobromide, 8.25-206.3 μg/mL; hyoscyamine sulfate, 15.01-750.76 μg/mL; and phenobarbital, 250-751 μg/mL. Recoveries from tablets were 100.8% for scopolamine hydrobromide, 100.1% for hyoscyamine sulfate, and 100.3% for phenobarbital. Replicate injections of scopolamine hydrobromide, hyoscyamine sulfate, and phenobarbital gave an overall relative standard deviation of <1.0% (n = 10). The method detected as little as 3.3 ng scopolamine hydrobromide.

Liquid Chromatographic Determination of Nifursol in Concentrates, Premixes, and Finished Turkey Feeds

1994 ◽  
Vol 77 (6) ◽  
pp. 1347-1352
Author(s):  
Ellen Jan De Vries ◽  
Richard C Bas ◽  
Henny Kuil
Keyword(s):  
Chromatographic Determination ◽  
Test Sample ◽  
Liquid Chromatographic Method ◽  
Limit Of Quantitation ◽  
Order Of Magnitude ◽  
Pelleted Feed ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Better Than

Abstract A specific liquid chromatographic method was developed for determination of nifursol in premixes and turkey feeds. Nifursol is extracted from test sample into tetrahydrofuran. Butylhydroxytoluene is added to prevent degradation of nifursol. The extract is diluted with tetrahydrofuran–water (50 + 50, v/v); an aliquot is injected onto a Zorbax ODS column. The mobile phase is water-acetonitrile (525 + 475, v/v) adjusted to an apparent pH of 3.5 with formic acid and ammonia. The wavelength of detection is 380 nm. The system can separate nifursol from dimetridazole and ronidazole. The method is specific; has linearity of more than one order of magnitude; and has a limit of quantitation in the 1–2 ppm range. Recovery averaged 98% or more, and the reproducibility had a coefficient of variation of better than 2.5% in pelleted feed.

Liquid Chromatographic Determination of Dicloxacillin Preparations: Interlaboratoiy Study

1993 ◽  
Vol 76 (5) ◽  
pp. 1143-1145 ◽  
Author(s):  
Mei-Chich Hsu ◽  
Weng F Huang
Keyword(s):  
Chromatographic Method ◽  
Chromatographic Determination ◽  
Performance Requirements ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic Determination ◽  
Repeatability And Reproducibility ◽  
The Individual ◽  
Liquid Chromatographic

Abstract A previously published liquid chromatographic method proposed for the analysis of dicloxacillin preparations was subjected to an interlaboratory study. The method is rigorously defined in terms of performance requirements, yet allows a degree of flexibility to the individual analyst. Eight laboratories participated in a study to analyze 3 samples in duplicate. Estimates for the repeatability and reproducibility of the method, expressed as relative standard deviations of the results of the determination of dicloxacillin preparations, were <0.57 and 2.56%, respectively.

Liquid Chromatographic Determination of Glyburide (Glibenclamide) and Its Related Compounds in Raw Materials

1993 ◽  
Vol 76 (5) ◽  
pp. 962-965
Author(s):  
Normand Beaulieu ◽  
Susan J Graham ◽  
Edward G Lovering
Keyword(s):  
Raw Materials ◽  
Chromatographic Determination ◽  
Assay Method ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Limit Of Quantitation ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Related Compounds

Abstract A liquid chromatographic method has been developed for the determination of glyburide and 3 known related compounds in drug raw materials. The lower limit of quantitation of the related compounds is about 0.02%. Evaluation of 9 drug raw materials revealed total impurities ranging from 0.17 to 0.65%. The relative standard deviation of the assay method is <1%.

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