Journal - Association of Official Analytical Chemists最新文献

Liquid chromatographic determination of paralytic shellfish poisons in shellfish after prechromatographic oxidation. 色谱前氧化贝类中麻痹性贝类毒素的液相色谱测定。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

J F Lawrence, C Ménard

{"title":"Liquid chromatographic determination of paralytic shellfish poisons in shellfish after prechromatographic oxidation.","authors":"J F Lawrence, C Ménard","doi":"","DOIUrl":"","url":null,"abstract":"A liquid chromatographic method for quantitating paralytic shellfish poison toxins in shellfish has been developed in which the toxins are converted to fluorescent purines by prechromatographic oxidation under mildly basic conditions with hydrogen peroxide or periodate. The addition of ammonium formate to the periodate oxidation reaction greatly improved the yield of fluorescent derivatives for neosaxitoxin, gonyautoxin-1, B-2, and C-3 compared to the same reaction without ammonium formate. As little as 3-6 ng of each of the nonhydroxylated toxins and 7-12 ng of the hydroxylated compounds per gram of shellfish could be detected. Reversed-phase chromatography using ammonium formate in the mobile phase improved the chromatography of neosaxitoxin and B-2 compared to results obtained earlier. Because the oxidation products of neosaxitoxin and B-2 could not be separated, parent compounds were separated before oxidation by using an SPE-COOH ion exchange cartridge. The repeatability coefficient of variation for the oxidation reactions ranged from 3 to 8% for the peroxide reaction, and from 4 to 11% for the periodate reaction, depending upon the individual toxin determined and its concentration in the extract (0.04-0.55 micrograms/g). The method was compared to the mouse bioassay and the postcolumn oxidation method. In most cases, results were comparable.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 6","pages":"1006-12"},"PeriodicalIF":0.0,"publicationDate":"1991-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12827507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Separation and determination of diesel contaminants in various fish products by capillary gas chromatography. 毛细管气相色谱法分离测定各种鱼类产品中柴油污染物。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

J M Newton, B S Rothman, F A Walker

引用次数: 0

An analytical survey of aflatoxins in tissues from swine grown in regions reporting 1988 aflatoxin-contaminated corn. 1988年玉米受黄曲霉毒素污染地区猪组织中黄曲霉毒素的分析调查。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

R D Stubblefield, J P Honstead, O L Shotwell

{"title":"An analytical survey of aflatoxins in tissues from swine grown in regions reporting 1988 aflatoxin-contaminated corn.","authors":"R D Stubblefield, J P Honstead, O L Shotwell","doi":"","DOIUrl":"","url":null,"abstract":"A joint project was undertaken by the Food Safety and Inspection Service (FSIS) and the Agriculture Research Service branches of the U.S. Department of Agriculture to determine the presence of aflatoxins in the U.S. meat supply during a drought year. In 1988, high incidences of aflatoxins occurred in corn grown in regions of the Midwest, Southeast, and South. Six states were identified as having serious aflatoxin contamination in their corn crop: Virginia, North and South Carolina, Texas, Iowa, and Illinois. Swine liver and pillars of diaphragm (muscle) tissues were sampled by federal FSIS Inspectors in plants located in these states. A worstcase sampling plan was conducted. Samples were taken in January 1989 from hogs fed corn soon after harvest and in April 1989 from hogs fed corn originally stored and then fed in the spring. A modification of the official AOAC method for the thin-layer chromatography (TLC) determination of aflatoxins in animal tissue was used to permit quantitation by LC with fluorescence detection. The official AOAC TLC confirmation of identity method was used to confirm all positive samples with B1 concentrations greater than 0.04 ppb and M1 concentrations greater than 0.1 ppb. Sixty samples in the January group and 100 samples in the April group were assayed. Concentrations of aflatoxins B1 and M1 in the first group of pig livers ranged from 0.04 to 0.06 ppb. The identity of aflatoxin B1 was confirmed in all positive samples. Aflatoxin M1 could not be confirmed in any of the positive liver samples because the method was insufficiently sensitive for this aflatoxin.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 6","pages":"897-9"},"PeriodicalIF":0.0,"publicationDate":"1991-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12920449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Liquid chromatographic determination of the processing aid 4-hexylresorcinol in shrimp. 虾中加工助剂4-己基间苯二酚的液相色谱测定。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

J M King, A J McEvily, R Iyengar

引用次数: 0

Bacillus stearothermophilus disk assay for determining ampicillin residues in fish muscle. 鱼肌肉中氨苄西林残留量测定的嗜热脂肪芽孢杆菌圆盘试验。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

S M Plakas, A DePaola, M B Moxey

引用次数: 0

Comparison of automated liquid chromatographic and bioassay methods for determining spiramycin concentration in bovine plasma. 自动液相色谱法和生物测定法测定牛血浆中螺旋霉素浓度的比较。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

P Sanders, G Moulin, C Gaudiche, B Delepine, D Mourot

引用次数: 0

GC/MIP/AED method for pesticide residue determination in fruits and vegetables. GC/MIP/AED法测定果蔬中农药残留

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01 DOI: 10.1093/JAOAC/74.6.991

K. Ting, P. Kho

{"title":"GC/MIP/AED method for pesticide residue determination in fruits and vegetables.","authors":"K. Ting, P. Kho","doi":"10.1093/JAOAC/74.6.991","DOIUrl":"https://doi.org/10.1093/JAOAC/74.6.991","url":null,"abstract":"This research describes the results of a gas chromatography/microwave induced plasma/atomic emission detection (GC/MIP/AED) method performed on a Hewlett-Packard 5921A system for pesticide residue analysis in fruits and vegetables. A total of 6 experiments were conducted: (1) sensitivity and linearity studies for elements S, P, Cl, and N by analyzing dursban; (2) a study of instrument response to Cl concentration in pesticide molecules; (3) organochlorinated pesticide recoveries; (4) organophosphate pesticide recoveries; (5) carbamate pesticide recoveries; and (6) investigation of metallic pesticides with plictran and vendex as standards. The rank according to sensitivity and linearity was found to be as follows: S-181 greater than P-178 greater than Cl-479 greater than N-174. Instrument response to the concentration of chlorine atoms in the pesticide molecule was linear, with a correlation coefficient of 0.89. Recoveries of organochlorinated pesticides were 91.7-109.3%, with the exception of citrus, whose recovery was affected by coeluting interferences. Organophosphate recoveries were 73.2% or higher, except for the cygon oxygen analog, which degraded in the GC system under all circumstances. Carbamate recoveries were inconsistent quantitatively; however, the information generated from elements N and S were useful for qualitative confirmation of other methods, such as LC postcolumn derivatization analysis. Overall, the GC/MIP/AED method is powerful for qualitative confirmation in pesticide residue analysis. The instrument's capability of acquiring multi-elements (Cl and P) selectively and accurately is an alternative method for organochlorinated and organophosphate pesticide residue analyses. In addition, the GC/MIP/AED system is easy to use, simple to maintain, and its chromatograms can be interpreted by any chromatography analyst without much prior training.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"51 1","pages":"991-8"},"PeriodicalIF":0.0,"publicationDate":"1991-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73348615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Sensitive and rapid reversed-phase liquid chromatography-fluorescence method for determining bisphenol A diglycidyl ether in aqueous-based food simulants. 灵敏快速反相液相色谱-荧光法测定水基食品模拟剂中双酚A二缩水甘油酯醚。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01 DOI: 10.1093/JAOAC/74.6.925

P. P. Losada, P. L. Mahía, L. Oderiz, J. Lozano, J. S. Gándara

引用次数: 19

GC/MIP/AED method for pesticide residue determination in fruits and vegetables. GC/MIP/AED法测定果蔬中农药残留

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

K C Ting, P Kho

{"title":"GC/MIP/AED method for pesticide residue determination in fruits and vegetables.","authors":"K C Ting, P Kho","doi":"","DOIUrl":"","url":null,"abstract":"This research describes the results of a gas chromatography/microwave induced plasma/atomic emission detection (GC/MIP/AED) method performed on a Hewlett-Packard 5921A system for pesticide residue analysis in fruits and vegetables. A total of 6 experiments were conducted: (1) sensitivity and linearity studies for elements S, P, Cl, and N by analyzing dursban; (2) a study of instrument response to Cl concentration in pesticide molecules; (3) organochlorinated pesticide recoveries; (4) organophosphate pesticide recoveries; (5) carbamate pesticide recoveries; and (6) investigation of metallic pesticides with plictran and vendex as standards. The rank according to sensitivity and linearity was found to be as follows: S-181 greater than P-178 greater than Cl-479 greater than N-174. Instrument response to the concentration of chlorine atoms in the pesticide molecule was linear, with a correlation coefficient of 0.89. Recoveries of organochlorinated pesticides were 91.7-109.3%, with the exception of citrus, whose recovery was affected by coeluting interferences. Organophosphate recoveries were 73.2% or higher, except for the cygon oxygen analog, which degraded in the GC system under all circumstances. Carbamate recoveries were inconsistent quantitatively; however, the information generated from elements N and S were useful for qualitative confirmation of other methods, such as LC postcolumn derivatization analysis. Overall, the GC/MIP/AED method is powerful for qualitative confirmation in pesticide residue analysis. The instrument's capability of acquiring multi-elements (Cl and P) selectively and accurately is an alternative method for organochlorinated and organophosphate pesticide residue analyses. In addition, the GC/MIP/AED system is easy to use, simple to maintain, and its chromatograms can be interpreted by any chromatography analyst without much prior training.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 6","pages":"991-8"},"PeriodicalIF":0.0,"publicationDate":"1991-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12920172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sensitive and rapid reversed-phase liquid chromatography-fluorescence method for determining bisphenol A diglycidyl ether in aqueous-based food simulants. 灵敏快速反相液相色谱-荧光法测定水基食品模拟剂中双酚A二缩水甘油酯醚。

Journal - Association of Official Analytical Chemists Pub Date : 1991-11-01

P Paseiro Losada, P López Mahía, L Vázquez Odériz, J Simal Lozano, J Simal Gándara

引用次数: 0