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The use of reference materials (RMs) is critical to improve measurements accuracy for validating and testing the accuracy of analytical protocols. To the best of our knowledge, there is no food-based matrix RM currently available for glyphosate. The
Brian J. Nablo, Jungjoon Ahn, Kiran Bhadriraju, Jong M. Lee, Darwin Reyes-Hernandez
Neutral red is a supravital stain that estimates the number of viable cells based on its accumulation and retention within lysosomes. The standard protocol relies on a destructive extraction process in order to spectrophotometrically quantify the amount of
The analysis of complex samples without extensive preparation steps (e.g., filtration or centrifugation) is a persistent challenge for applications ranging from forensic identification to high-throughput security screening. Here, a capillary-based
Katrice A. Lippa, Mary Bedner, Susan Tai, Carolyn Q. Burdette
The National Institute of Standards and Technology (NIST) established a Vitamin D Metabolites Quality Assurance Program (VitDQAP) in collaboration with the National Institutes of Health Office of Dietary Supplements (NIH-ODS) in 2009. The VitDQAP at NIST
Xinyu Li, Maribel Garc?a-Ib??ez, Brendan Carter, Baoshen Chen, Qian Li, Regina Easley, Wei-Jun Cai
Ocean acidification, a phenomenon of seawater pH decreasing due to increasing atmospheric CO2, has a global effect on seawater chemistry, marine biology, and ecosystems. Ocean acidification is a gradual and global long-term process that demands high
The chemical analysis of homemade explosives (HMEs) and improvised explosive devices (IEDs) remains challenging for fieldable analytical instrumentation and sensors. Complex explosive fuel-oxidizer mixtures, black and smokeless powders, flash powders, and
Interaction polymer chromatography (IPC) is an umbrella term covering a large variety of primarily enthalpically-dominated macromolecular separation methods. These include temperature- gradient interaction chromatography, interactive gradient polymer
Nicholas Ritchie, Dale E. Newbury, John Fournelle, Aurelien Moy, Heather Lowers, Anette von der Handt, Paul Carpenter, Emma Bullock, John Donovan
The electron excited microanalysis community is increasingly running into the limitations of its ability to derive accurate an composition from measured x-ray intensities. Many of these limitations could be mitigated if the standard matrix correction
Partition coefficients describe the relative concentration of a chemical equilibrated between two phases. In the design of air samplers, the sorbent-air partition coefficient is a critical parameter, as is the ability to extrapolate or predict partitioning
NIST Special Publication (SP) 922 is an aid in the identification of the chemical structures of polycyclic aromatic hydrocarbons (PAHs). The Structure Index consists of two parts: (1) a cross index of named PAHs listed in alphabetical order and (2)
Meryl B. Cruz, Benjamin Place, Laura J. Wood, Aaron A. Urbas, Werickson Rocha, Andrzej Wasik
The lack of stringent regulations regarding raw materials for herbal supplements used for medicinal purposes has been a constant challenge in the industry. Ginkgo biloba L. leaf extracts attract consumers because of the supposed positive effect on mental