Journal - Association of Official Analytical Chemists最新文献_第8页

Modifications to the official method for testing chlortetracycline HCl in animal feeds. 动物饲料中盐酸氯霉素官方检测方法的修改。

Journal - Association of Official Analytical Chemists Pub Date : 1991-09-01

M L Hasselberger

引用次数: 0

Performance characteristics of methods of analysis used for regulatory purposes. Part II. Pesticide formulations. 用于监管目的的分析方法的性能特征。第二部分。农药剂型。

Journal - Association of Official Analytical Chemists Pub Date : 1991-09-01

W Horwitz, R Albert

{"title":"Performance characteristics of methods of analysis used for regulatory purposes. Part II. Pesticide formulations.","authors":"W Horwitz, R Albert","doi":"","DOIUrl":"","url":null,"abstract":"The precision parameters of the method-performance (collaborative) studies published in the AOAC Journal from 1915 through 1990 for pesticide formulations have been recalculated on a uniform basis by the International Union of Pure and Applied Chemistry 1987 protocol. About 93% of the 953 accepted assays, which are predominantly gravimetric (G), volumetric (V), and gas (GC) and liquid (LC) chromatographic methods, exhibit relative standard deviations among laboratories (RSDR) that are generally less than 2 times the values predicted from the Horwitz equation: RSDR (%) = 2 exp (1-0.5 log C), where C is the concentration expressed as a decimal fraction. UV, VIS, and IR spectrophotometric (S) methods are somewhat poorer, with about 80% of the reported RSDR values less than twice the predicted RSDR value. The precision parameters of pesticide formulations analyzed by the older methods (G, V, GC) are equivalent to those previously found for drug preparations in the same concentration range; the precision parameters of pesticide formulations analyzed by LC and S are somewhat poorer. Overall, however, the precision parameters of pesticide formulations are generally independent of analyte, method, and matrix, and are primarily a function of concentration. The method-acceptability decisions of the AOAC for pesticide formulations during the past 75 years can be approximated retrospectively by using a criterion for RSDR that is less than 2 times the RSDR calculated from the Horwitz equation.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 5","pages":"718-44"},"PeriodicalIF":0.0,"publicationDate":"1991-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12947400","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

Validation of methods used in the Florida Department of Agricultural and Consumer Services' Chemical Residue Laboratory. 佛罗里达州农业和消费者服务部化学残留实验室使用的方法的验证。

Journal - Association of Official Analytical Chemists Pub Date : 1991-09-01

G A Parker

{"title":"Validation of methods used in the Florida Department of Agricultural and Consumer Services' Chemical Residue Laboratory.","authors":"G A Parker","doi":"","DOIUrl":"","url":null,"abstract":"Very few methods for detecting residues of pesticides in food or agricultural samples have undergone rigorous colloborative study and possess official AOAC status. The Chemical Residue Laboratory has formalized a method validation scheme to use when incorporating or developing new, unofficial methods. These methods are validated by assessing certain performance parameters: scope, specificity, linear range, accuracy, precision, limit of detection (LOD), and limit of quantitation (LOQ). For accuracy and precision assessment, 12 replicate fortifications must yield recoveries within the range of 70-120% with a coefficient of variation (CV) that compares favorably to the Horwitz CV. LOD and LOQ are equivalent to 3 and 10 times, respectively, the background signal contributed by a sample matrix blank. This criterion that we use for LOD/LOQ is not universal. In fact, because of differing definitions, we have encountered difficulties in enforcing a tolerance by using a registrant's method. This paper also presents an example of our method validation scheme, using a recent method development project for detecting sulfamethazine in raw milk. The sulfamethazine project also revealed unanticipated personnel problems, underscoring the importance of the human factor in quality assurance.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 5","pages":"868-71"},"PeriodicalIF":0.0,"publicationDate":"1991-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12945742","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

Quantitation of the nitrosamine 2-ethylhexyl-4-(N-methyl-N-nitrosoamino) benzoate (NPABAO) in sunscreen products. 防晒产品中亚硝胺2-乙基己基-4-(n -甲基-n -亚硝基氨基)苯甲酸酯(NPABAO)的含量测定。

Journal - Association of Official Analytical Chemists Pub Date : 1991-09-01

T A Meyer, J B Powell

{"title":"Quantitation of the nitrosamine 2-ethylhexyl-4-(N-methyl-N-nitrosoamino) benzoate (NPABAO) in sunscreen products.","authors":"T A Meyer, J B Powell","doi":"","DOIUrl":"","url":null,"abstract":"We have devised a method to quantitate the nitrosamine, 2-ethylhexyl-4-(N-methyl-N-nitrosoamino) benzoate (NPABAO), in commercial products containing the sunscreen ingredient, Padimate O. The method involves a minimum of cleanup steps to afford a nonaqueous extract from product emulsions suitable for analysis by a liquid chromatograph interfaced to a thermal energy analyzer (LC/TEA). The method is applicable to lotions, creams, and gels. Oils are normally soluble in the mobile phase and can be analyzed directly on the LC/TEA without additional cleanup procedures. The method has a minimum detectable limit of about 30 ppb and yields greater than 80% recovery. It is highly reproducible and generates no NPABAO artifactually prior to quantitation on the LC/TEA. Application of the method to 22 different commercial product formulas disclosed that the level of NPABAO in each of the products is below 250 ppb, with 18 of the products containing less than 100 ppb. Of interest was the observation that musk ketone, a common fragrance constituent, produces a false-positive TEA response that can interfere with accurate analysis of NPABAO content in typical commercial products.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 5","pages":"766-71"},"PeriodicalIF":0.0,"publicationDate":"1991-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13004026","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

Recovery of Salmonella from shell eggs. 从带壳鸡蛋中回收沙门氏菌。

Journal - Association of Official Analytical Chemists Pub Date : 1991-09-01 DOI: 10.1093/JAOAC/74.5.821

P. Stephenson, F. Satchell, G. Allen, W. Andrews

{"title":"Recovery of Salmonella from shell eggs.","authors":"P. Stephenson, F. Satchell, G. Allen, W. Andrews","doi":"10.1093/JAOAC/74.5.821","DOIUrl":"https://doi.org/10.1093/JAOAC/74.5.821","url":null,"abstract":"A preenrichment procedure and a direct selective enrichment procedure were compared for recovery of Salmonella artificially inoculated into liquid whole egg, egg yolk, and egg albumen. For liquid whole egg and egg yolk, the 2 procedures were comparable. With egg albumen, however, preenrichment in lactose broth gave significantly higher recoveries than did direct selective enrichment in either selenite cystine or tetrathlonate broths. The lactose preenrichment procedure was used to determine the survival of S. enteritidis in egg yolk and egg albumen over a period of 7 days. As shown by most probably number determinations, counts of S. enteritidis inoculated into egg albumen decreased by 3 log units, whereas those in egg yolk did not change significantly. It is recommended, therefore, that only the egg yolk be examined for this pathogen. In a comparison of 5 different preenrichment media (lactose broth, brain heart infusion broth, trypticase soy broth, buffered peptone water, and nutrient broth), lactose broth was somewhat less productive than the other 4 media for the recovery of Salmonella from egg yolks. Trypticase soy broth gave the highest recovery.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"11 1","pages":"821-6"},"PeriodicalIF":0.0,"publicationDate":"1991-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81922579","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: 19

Symposium on microbiology update: old friends and new enemies. Listeria monocytogenes. 微生物学研讨会最新进展:老朋友和新敌人。单核细胞增多性李斯特氏菌。

Journal - Association of Official Analytical Chemists Pub Date : 1991-07-01

J M Farber

{"title":"Symposium on microbiology update: old friends and new enemies. Listeria monocytogenes.","authors":"J M Farber","doi":"","DOIUrl":"","url":null,"abstract":"Listeria monocytogenes, one of the \"new enemies\" in food microbiology, is a human and animal pathogen that is widespread in nature. The organism is a transient constituent of the intestinal flora excreted by 1-10% of healthy humans. It is an extremely hardy organism and can survive for many years in the cold in naturally infected sources. L. monocytogenes has been isolated from a wide variety of foods, including dairy products, meats, and fish. Although most of the foodborne listeriosis outbreaks have been linked to the consumption of dairy products, recent sporadic cases have been associated with meats, as well as other foods. It is now recognized that listeriolysin 0, a 60-kilodalton protein, is one of the major virulence factors of the organism. All strains of L. monocytogenes are pathogenic by definition although some appear to be more virulent than others. There have been recent reports of hemolytic isolates of L. monocytogenes, which are nonpathogenic for mice. Attachment to and penetration of cells also appear to be prerequisites for human infection. Cultural methodology for isolating the organism from foods has been in a state of flux since 1985. Rapid methods using both ELISA and DNA technology have been developed. Because of the widespread nature of the organism, it is nearly impossible to eliminate it from the food supply. However, by using a hazard analysis-critical control point approach, the health hazard associated with this organism can be reduced to a minimum.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 4","pages":"701-4"},"PeriodicalIF":0.0,"publicationDate":"1991-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13076947","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 fluometuron and metabolites in soil 土壤中荧光素及其代谢物的液相色谱测定

Journal - Association of Official Analytical Chemists Pub Date : 1991-07-01 DOI: 10.1093/JAOAC/74.4.671

T. Mueller, T. Moorman

引用次数: 12

Dry rehydratable film for enumeration of total coliforms and Escherichia coli in foods: collaborative study. 用于食品中总大肠菌群和大肠杆菌计数的干燥可再水化薄膜:合作研究。

Journal - Association of Official Analytical Chemists Pub Date : 1991-07-01 DOI: 10.1093/JAOAC/74.4.635

M. Curiale, T. Sons., D. McIver, J. Mcallister, B. Halsey, D. Roblee, T. L. Fox

引用次数: 22

A rapid method for the determination of chlorine, phosphorus, and sulfur in flours of grains and legumes using wavelength dispersive x-ray flourescence spectrometry. 用波长色散x射线荧光光谱法快速测定谷物和豆类中氯、磷和硫的方法。

Journal - Association of Official Analytical Chemists Pub Date : 1991-07-01 DOI: 10.1093/JAOAC/74.4.625

T. Pérez Ruiz, M. Hernández Córdoba, R. González

引用次数: 4

Multiresidue matrix solid phase dispersion (MSPD) extraction and gas chromatographic screening of nine chlorinated pesticides in catfish (Ictalurus punctatus) muscle tissue. 多残留基质固相分散(MSPD)提取和气相色谱法筛选鲶鱼肌肉组织中9种氯农药。

Journal - Association of Official Analytical Chemists Pub Date : 1991-07-01

A R Long, M D Crouch, S A Barker

{"title":"Multiresidue matrix solid phase dispersion (MSPD) extraction and gas chromatographic screening of nine chlorinated pesticides in catfish (Ictalurus punctatus) muscle tissue.","authors":"A R Long, M D Crouch, S A Barker","doi":"","DOIUrl":"","url":null,"abstract":"A multiresidue technique for extraction and gas chromatographic screening of 9 insecticide (lindane, heptachlor, aldrin, heptachlor epoxide, p,p'-DDE, dieldrin, endrin, p,p'-TDE, and p,p'-DDT) residues in catfish (Ictalurus punctatus) muscle tissue is presented. The 9 insecticides, plus dibutyl chlorendate internal standard, were fortified into catfish muscle tissue (0.5 g) and blended with 2 g C18 (octadecylsilyl derivatized silica reverse-phase material). The C18/muscle tissue matrix blend was fashioned into a column by adding the blend to a 10 mL syringe barrel containing 2 g activated Florisil. The insecticides were then eluted from the column with acetonitrile (8 mL), and a portion (2 microL) of the acetonitrile eluate was then directly analyzed by gas chromatography with electron capture detection. Unfortified blank controls were treated similarly. The resultant extracts contained pesticide analytes (31.25-500 ng/g) free of interfering compounds when analyzed. Correlation coefficients for the 9 extracted pesticide standard curves (linear regression analysis, n = 5) ranged from 0.9967 (+/- 0.0018) to 0.9999 (+/- 0.0001). Average percentage recoveries (82 +/- 4.8% to 97 +/- 3.6%, n = 25 for each insecticide), interassay (5.0 +/- 2.7% to 16.9 +/- 6.5%, n = 25 for each insecticide) and intraassay (1.8 to 4.7%, n = 5 for each insecticide) variabilities were indicative of an acceptable methodology for the analysis and screening of these residues in catfish muscle tissue.","PeriodicalId":14752,"journal":{"name":"Journal - Association of Official Analytical Chemists","volume":"74 4","pages":"667-70"},"PeriodicalIF":0.0,"publicationDate":"1991-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13076943","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