138 Analytical Methods for Organometallic Chelation Testing

Edward Walker

doi:10.1093/jas/skaa054.247

138 Analytical Methods for Organometallic Chelation Testing

Journal of Animal Science ◽

10.1093/jas/skaa054.247 ◽

2020 ◽

Vol 98 (Supplement_3) ◽

pp. 141-142

Author(s):

Edward Walker

Keyword(s):

Analytical Methods ◽

Electrochemical Techniques ◽

Metal Compounds ◽

Standard Methods ◽

Methods Of Analysis ◽

Number Of Factors ◽

Manufactured Products ◽

Daunting Challenge ◽

Potential Use

Abstract Chelated minerals have increasingly captured the attention of scientists, manufacturers, and consumers in nutritional markets during the past five decades, due to their enhanced bioavailability compared to traditional ionic metal compounds. A wide variety of organic ligands bind to metal ions to form complexes that are generally referred to as chelates, including amino acids, peptides, proteins and carboxylic acids. Chemical reactions used to synthesize mineral chelates are affected by a number of factors that can alter the extent of chelation in manufactured products, such as pH, temperature, concentration, solvation, competing ions and ligands, and other variables. Qualitative and quantitative determination of chelation can be a daunting challenge, especially for dilute micronutrient minerals in complex matrices. Measuring chelation between metals and their ligands specifically focuses on the attractive forces between them. Analytical methods to determine the extent of chelation rely on a wide array of spectroscopic and electrochemical techniques. Very few standard methods of analysis exist to quantitatively measure the extent of chelation in nutritional products. A variety of these methods will be reviewed and compared for their potential use as standard methods of analysis.

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Electroanalysis of Tricyclic Psychotropic Drugs using Modified Electrodes

Current Analytical Chemistry ◽

10.2174/1573411014666180917112548 ◽

2019 ◽

Vol 15 (4) ◽

pp. 423-442 ◽

Cited By ~ 1

Author(s):

Mona Habibi-Kool-Gheshlaghi ◽

Farnoush Faridbod ◽

Mahya Karami Mosammam ◽

Mohammad Reza Ganjali

Keyword(s):

Psychotropic Drugs ◽

Analytical Methods ◽

Electrochemical Techniques ◽

Modified Electrodes ◽

Electroanalytical Methods ◽

Drug Assays ◽

Medical Importance ◽

Tricyclic Rings ◽

Easy Operation

Background: Tricyclic psychotropic drugs are defined as a tricyclic rings of the dibenzazepine group with the presence of sulfur and nitrogen atoms. They have been prescribed for antidepressive therapy over the years. Due to their medical importance, many analytical methods have been developed for their monitoring. However, benefits of electrochemical techniques such as costeffectiveness, fast, easy operation and non-destructiveness make them appropriate analytical methods for drug assays. Electrochemical determinations of pharmaceuticals require suitable working electrodes. During years, many electrodes are modified by a variety of modifiers and several sensors were developed based on them. In this regard, nanomaterials, due to their remarkable properties, are one of the most important choices. Objective: Here, the application of electroanalytical methods in the determination of electroactive tricyclic psychotropic drugs will be reviewed and the nanomaterials which are used for improvements of the working electrodes will be considered.

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Instrumental Analysis of Chlordiazepoxide in Different Matrices

International Research Journal of Multidisciplinary Technovation ◽

10.34256/irjmt2151 ◽

2021 ◽

pp. 1-10

Author(s):

Lobna M. Abdel-Aziz ◽

Ahmed A. Soror ◽

Ahmed A. Hassan ◽

Ahmed S. Ali ◽

Ahmed A. Hafez ◽

...

Keyword(s):

Literature Review ◽

Biological Samples ◽

Analytical Methods ◽

Degradation Products ◽

Electrochemical Techniques ◽

Pharmacological Action ◽

Pure Form ◽

Instrumental Analysis ◽

The World

Chlordiazepoxide is considered one of most important sedative and hypnotic benzodiazepines drugs which is currently used all over the world with the increased rate of anxiety drugs. In this literature review, we will introduce the pharmacological action of this drug in addition to most of up-to-date reported methods that have been developed for determination of chlordiazepoxide in its pure form, combined form with other drugs, combined form with degradation products, and in biological samples. Most of the reported analytical methods will focus on spectroscopic, chromatographic and electrochemical techniques.

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Liaison Report on Malt Beverages and Brewing Materials

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/52.6.1161 ◽

1969 ◽

Vol 52 (6) ◽

pp. 1161-1165

Author(s):

Irwin Stone

Keyword(s):

Analytical Methods ◽

Alternative Procedure ◽

Brewing Industry ◽

Comprehensive Program ◽

Methods Of Analysis ◽

Official Methods Of Analysis

Abstract Two new A SBC methods for beer analysis are presented to the AOAC for adoption: “Alcohol by Kefractometer” and “Beer Bitterness.” The first is a rapid alternative procedure to the present distillation technique. The latter replaces, in part, the isohumulones methods now used. The new edition of Official Methods of Analysis will also contain the “Total Haze After Chilling” method which partly replaces turbidity 10.010–10.015. The ASBC now has 12 technical subcommittees working on a comprehensive program for the development and testing of new analytical methods of interest to the brewing industry. Two additional subcommittees will probably be authorized to investigate the determination of traces of heptyl-p-hydroxybenzoate and tannins in beer, both of which are of interest to the AOAC.

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Precision Parameters of Standard Methods of Analysis for Dairy Products

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/72.5.784 ◽

1989 ◽

Vol 72 (5) ◽

pp. 784-806 ◽

Cited By ~ 7

Author(s):

James T Peeler ◽

William Horwitz ◽

Richard Albert

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Freezing Point ◽

Milk Products ◽

Standard Methods ◽

Methods Of Analysis ◽

Collaborative Studies ◽

Relative Standard ◽

Repeatability And Reproducibility

Abstract The available collaborative studies for standard methods of analysis for various constituents of milk and milk products were examined in an attempt to assign specific repeatability and reproducibility precision parameters to these methods. The different collaborative assays for the primary constituents (moisture/solids, fat, protein), the nutritionally important elements (calcium, sodium, potassium, phosphorus), and miscellaneous analytes/physical constants (ash, lactose, salt, freezing point) produced different estimates of the precision parameters for the same method. A suitable summary of the precision estimates from collaborative studies is given by the reproducibility relative standard deviation, RSDR, which is relatively constant within a product and permits comparisons across products. An estimate of the variation of RSDR for an analyte from a number of collaborative studies is presented in terms of the median and 90% interval (the range of the centermost 90% of values). These estimates are only informative when a substantial number of independent studies are available for pooling the independent estimates to form a distribution of RSDR values. The RSDR for the determination of the primary constituents of milk and milk products is characterized by a median RSDR of 1% and a 90% interval of 0.3-3%, with RSDR estimates occasionally occurring below 0.3% and above 4%. These overall estimates appear to be independent of analyte, matrix, and method and apply to concentrations of primary constituents that range from about 2 to 80%. The repeatability relative standard deviation, RSDR, is unstable, although it tends to converge to about 0.5-0.7 X RSDR. Too few collaborative assays are available to characterize RSDR for the determination of certain other constituents (acidity, ash, lactose, salt, and the nutritionally important elements) unless RSDR values for different analytes, methods, and matrixes are pooled on the basis of similar analyte concentrations. When pooled, the RSDR values are generally better than predicted from the Horwitz equation, RSDR (%) = 2 exp (1—0.5 logioC), where C is the concentration expressed as a decimal fraction; all but one of 661 RSDR values are within the upper empirical limit of twice this curve.

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