Practice for Preparation of Liquid Blends for Use as Analytical Standards

2021 ◽  
Author(s):  
Keyword(s):  
Analytical Standards

scholarly journals Development and Validation of a UHPLC-qTOF MS Method for the Determination of Sorbitol-Based Nuclear Clarifying Agents in Food Simulants after Migration from Food Contact Materials

2021 ◽  
Vol 11 (9) ◽  
pp. 3789
Author(s):  
Emmanouil D. Tsochatzis ◽  
Georgios Theodoridis ◽  
Helen G. Gika
Keyword(s):  
A Posteriori ◽  
Contact Materials ◽  
Food Contact ◽  
Food Simulants ◽  
Target Analytes ◽  
Commission Regulation ◽  
Development And Validation ◽  
Migration Testing ◽  
Analytical Standards

Nuclear clarifying agents (NCAs) are a class of substances frequently used as additives in the production of polymers to improve their physical properties. Some are EU regulated under Commission Regulation (EU) no. 10/2011 can be used as additives in the production of food contact plastics. However, limited analytical methods for their analysis are currently available, in part due to poor solubility in most common organic solvents and lack of analytical standards of known purity. In this work, a simple and sensitive method was developed to analyze 4 EU-regulated sorbitol-based nucleating agents in food simulants, following solubility studies to establish effective solvents. The method was shown to be accurate and precise and can be used with official food simulant D1 (50% v/v ethanol/H2O). Application to other ethanolic simulants is also possible, but due to solubility issues, a posteriori conversion of those simulants into simulant D1 is required. Finally, the method was applied to quantify the target analytes in simulants after migration testing with polypropylene (PP) beverage cups.

scholarly journals Pyrrolidinyl Synthetic Cathinones α-PHP and 4F-α-PVP Metabolite Profiling Using Human Hepatocyte Incubations

2020 ◽  
Vol 22 (1) ◽  
pp. 230
Author(s):  
Jeremy Carlier ◽  
Xingxing Diao ◽  
Raffaele Giorgetti ◽  
Francesco P. Busardò ◽  
Marilyn A. Huestis
Keyword(s):  
Metabolite Profiling ◽  
Human Liver ◽  
Liver Microsomes ◽  
Drug Market ◽  
Metabolite Profile ◽  
Illegal Drug ◽  
Human Hepatocyte ◽  
Synthetic Cathinones ◽  
Metabolic Fate ◽  
Analytical Standards

For more than ten years, new synthetic cathinones (SCs) mimicking the effects of controlled cocaine-like stimulants have flooded the illegal drug market, causing numerous intoxications and fatalities. There are often no data on the pharmacokinetics of these substances when they first emerge onto the market. However, the detection of SC metabolites is often critical in order to prove consumption in clinical and forensic settings. In this research, the metabolite profile of two pyrrolidinyl SCs, α-pyrrolidinohexaphenone (α-PHP) and 4′′-fluoro-α-pyrrolidinovalerophenone (4F-α-PVP), were characterized to identify optimal intake markers. Experiments were conducted using pooled human hepatocyte incubations followed by liquid chromatography–high-resolution tandem mass spectrometry and data-mining software. We suggest α-PHP dihydroxy-pyrrolidinyl, α-PHP hexanol, α-PHP 2′-keto-pyrrolidinyl-hexanol, and α-PHP 2′-keto-pyrrolidinyl as markers of α-PHP use, and 4F-α-PVP dihydroxy-pyrrolidinyl, 4F-α-PVP hexanol, 4F-α-PVP 2′-keto-pyrrolidinyl-hexanol, and 4F-α-PVP 2′-keto-pyrrolidinyl as markers of 4F-α-PVP use. These results represent the first data available on 4F-α-PVP metabolism. The metabolic fate of α-PHP was previously studied using human liver microsomes and urine samples from α-PHP users. We identified an additional major metabolite (α-PHP dihydroxy-pyrrolidinyl) that might be crucial for documenting exposure to α-PHP. Further experiments with suitable analytical standards, which are yet to be synthesized, and authentic specimens should be conducted to confirm these results.

scholarly journals Current Trends and Challenges for Rapid SMART Diagnostics at Point-of-Site Testing for Marine Toxins

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2499
Author(s):  
Michael Dillon ◽  
Maja A. Zaczek-Moczydlowska ◽  
Christine Edwards ◽  
Andrew D. Turner ◽  
Peter I. Miller ◽  
...  
Keyword(s):  
Method Development ◽  
Regulatory Control ◽  
Detection Methods ◽  
Control Individual ◽  
Mouse Bioassay ◽  
Future Market ◽  
Site Testing ◽  
Wide Range ◽  
Development And Validation ◽  
Analytical Standards

In the past twenty years marine biotoxin analysis in routine regulatory monitoring has advanced significantly in Europe (EU) and other regions from the use of the mouse bioassay (MBA) towards the high-end analytical techniques such as high-performance liquid chromatography (HPLC) with tandem mass spectrometry (MS). Previously, acceptance of these advanced methods, in progressing away from the MBA, was hindered by a lack of commercial certified analytical standards for method development and validation. This has now been addressed whereby the availability of a wide range of analytical standards from several companies in the EU, North America and Asia has enhanced the development and validation of methods to the required regulatory standards. However, the cost of the high-end analytical equipment, lengthy procedures and the need for qualified personnel to perform analysis can still be a challenge for routine monitoring laboratories. In developing regions, aquaculture production is increasing and alternative inexpensive Sensitive, Measurable, Accurate and Real-Time (SMART) rapid point-of-site testing (POST) methods suitable for novice end users that can be validated and internationally accepted remain an objective for both regulators and the industry. The range of commercial testing kits on the market for marine toxin analysis remains limited and even more so those meeting the requirements for use in regulatory control. Individual assays include enzyme-linked immunosorbent assays (ELISA) and lateral flow membrane-based immunoassays (LFIA) for EU-regulated toxins, such as okadaic acid (OA) and dinophysistoxins (DTXs), saxitoxin (STX) and its analogues and domoic acid (DA) in the form of three separate tests offering varying costs and benefits for the industry. It can be observed from the literature that not only are developments and improvements ongoing for these assays, but there are also novel assays being developed using upcoming state-of-the-art biosensor technology. This review focuses on both currently available methods and recent advances in innovative methods for marine biotoxin testing and the end-user practicalities that need to be observed. Furthermore, it highlights trends that are influencing assay developments such as multiplexing capabilities and rapid POST, indicating potential detection methods that will shape the future market.

scholarly journals Exploring Secondary Metabolite Profiles of Stachybotrys spp. by LC-MS/MS

Toxins ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 133 ◽  
Author(s):  
Annika Jagels ◽  
Viktoria Lindemann ◽  
Sebastian Ulrich ◽  
Christoph Gottschalk ◽  
Benedikt Cramer ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Future Research ◽  
Structural Modifications ◽  
Metabolite Profiles ◽  
The Individual ◽  
First Time ◽  
Analytical Standards ◽  
Respective Species

The genus Stachybotrys produces a broad diversity of secondary metabolites, including macrocyclic trichothecenes, atranones, and phenylspirodrimanes. Although the class of the phenylspirodrimanes is the major one and consists of a multitude of metabolites bearing various structural modifications, few investigations have been carried out. Thus, the presented study deals with the quantitative determination of several secondary metabolites produced by distinct Stachybotrys species for comparison of their metabolite profiles. For that purpose, 15 of the primarily produced secondary metabolites were isolated from fungal cultures and structurally characterized in order to be used as analytical standards for the development of an LC-MS/MS multimethod. The developed method was applied to the analysis of micro-scale extracts from 5 different Stachybotrys strains, which were cultured on different media. In that process, spontaneous dialdehyde/lactone isomerization was observed for some of the isolated secondary metabolites, and novel stachybotrychromenes were quantitatively investigated for the first time. The metabolite profiles of Stachybotrys species are considerably influenced by time of growth and substrate availability, as well as the individual biosynthetic potential of the respective species. Regarding the reported adverse effects associated with Stachybotrys growth in building environments, combinatory effects of the investigated secondary metabolites should be addressed and the role of the phenylspirodrimanes re-evaluated in future research.

Molar Absorptivity Values for Aflatoxins and Justification for Their Use as Criteria of Purity of Analytical Standards

1970 ◽  
Vol 53 (1) ◽  
pp. 96-101 ◽  
Author(s):  
J V Rodricks ◽  
L Stoloff ◽  
W A Pons ◽  
J A Robertson ◽  
L A Goldblatt
Keyword(s):  
Thin Layer ◽  
Statistical Study ◽  
Molar Absorptivity ◽  
Confidence Limits ◽  
Components Of Variance ◽  
Significant Difference ◽  
Single Determination ◽  
Comparison Measurements ◽  
Analytical Standards

Abstract Measurements of molar absorptivities in methanol were carried out by two laboratories on samples of anatoxins Bi and Gi prepared and purified independently in four laboratories and on samples of aflatoxins B2 and G2 prepared and purified independently in three laboratories. Molar absorptivities of pure aflatoxins Bi, B2, G1, and G2 in benzene-acetonitrile (98 + 2) were determined at two laboratories. With the exception of aflatoxin G2, no significant difference between aflatoxin samples could be demonstrated. Molar absorptivity values and absorbance ratios for each aflatoxin, based on these data, are given. Statistical 95% confidence limits were established for a single determination of molar absorptivity. A statistical study was made of the components of variance which contribute to the accuracy of the determination of molar absorptivity. A comparison of the fluorescence intensities of spots of various aflatoxin preparations, developed on silica gel-coated thin layer plates, with the amount of aflatoxin in each spotting solution as determined by absorbance measurements, demonstrated the validity of using absorbance and fluorescence comparison measurements for aflatoxin quantitation.

Analytical standards for the analysis of chrysotile asbestos in ambient environments

1985 ◽  
Vol 57 (1) ◽  
pp. 204-208 ◽  
Author(s):  
John A. Small ◽  
Eric B. Steel ◽  
Patrick J. Sheridan
Keyword(s):  
Chrysotile Asbestos ◽  
Analytical Standards

scholarly journals Parâmetros de qualidade físico-química de óleos e análise morfométrica de frutos e sementes da espécie Orbignya phalerata Martius por região ecológica

2017 ◽  
Vol 41 (1) ◽  
pp. 74 ◽  
Author(s):  
Débora Silva Santos ◽  
Ilna Gomes da Silva ◽  
Maria Do Carmo Lacerda Barbosa ◽  
Maria Do Desterro Soares Brandão Nascimento ◽  
Maria Célia Pires Costa
Keyword(s):  
Physicochemical Parameters ◽  
Refraction Index ◽  
Physicochemical Characteristics ◽  
The State ◽  
National Standard ◽  
Morphometric Characteristics ◽  
Acidity Index ◽  
Ecological Region ◽  
Analytical Standards ◽  
Current Standards

This study aimed at the investigation of physicochemical characteristics of oils and the morphometric characteristics of fruits and seeds (almonds) of babassu (Orbignya phalerata Martius), by ecological region of the state of Maranhão. For this, samples of babassu were obtained from the following regions: Litoral, Cocais, Baixada, Cerrado and Pre-Amazonia of the state of Maranhão, and analyzed the following physicochemical parameters: acidity index, saponification index, refraction index and humidity using Analytical Standards of the Adolfo Lutz Institute. Fruits were collected from the same regions to analyze the morphometric characteristics by measuring the fruits and almonds of the studied species. The results indicate that the acidity indexes are within the maximum limit established by the ANVISA National Standard and the saponification indexes indicate the presence of medium to high molecular weight lipids. The refractometric results are in line with current standards and the moisture content was less than 1%. The lots of Orbignya phalerata Martius babassu presented a significant variability in size and weight for fruits and almonds by region.

scholarly journals Pharmacognostic Investigation of Leaves and Bark of Cochlospermum Religiosum Linn

2021 ◽  
Vol 23 (2) ◽  
Author(s):  
Patrakar Ramling G ◽  
◽  
Bhusnure Omprakash G ◽  
Keyword(s):  
Calcium Oxalate ◽  
Diagnostic Tool ◽  
Microscopic Examination ◽  
Stem Bark ◽  
Physicochemical Analysis ◽  
Xylem Vessel ◽  
Starch Grains ◽  
Sodium Calcium ◽  
Anomocytic Stomata ◽  
Analytical Standards

Cochlospermum religiosum (Linn.) Alston. (Bixaceae) otherwise known as Yellow silk cotton tree.Traditionally, the plant is used in the treatment of cough, asthma, jaundice, tuberculosis, inflammation, gonorrhea, fever and dysentery. In the present studymicromorphological investigations and the physicochemical analysis of Cochlospermum religiosumleaves and stem bark were carried out.The macromorphological examination indicated simple, palmately lobed, alternate distichous leaves possessing the prominent parallel venation, acute apices and crenate margin. Similarly, smooth, fibrous, ash coloured bark containing an orange-coloured gummy exudate observed. The microscopy of leaves presented a dorsiventral lamina, long filamentous unicellular uniseriate covering trichomes, anomocytic stomata, annulated lignified xylem vessel, mucilaginous brown matter, starch grains and prisms of calcium oxalate whereas the microscopic examination of the bark indicated lignified cork cells, thick-walled lignified sclereids, bundles of lignified fibres, rounded starch grains, elongated cellulosic medullary rays, tetragonal and rosette crystals of calcium oxalate. Thequalitative analysis of inorganic elementsexhibited the presence of aluminium, sodium, calcium, chlorides and ironin leaves and the bark ofCochlospermum religiosum.The present investigation on pharmacognostic characters and analytical standards of Cochlospermum religiosumwill provide a diagnostic tool in the authentication and the assessment of its quality.

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