8 research outputs found
Nomenclature in laboratory robotics and automation
These recommended terms have been prepared to help provide a uniform approach to terminology and notation in laboratory automation and robotics. Since the terminology used in laboratory automation and robotics has been derivedfrom diverse backgrounds, it is often vague, imprecise, and in some cases, in conflict with classical automation and robotic nomenclature. These definitions have been assembledfrom standards, monographs, dictionaries, journal articles, and documents of international organizations emphasizing laboratory and industrial automation and robotics. When appropriate, definitions have been taken directly from the original source and identified with that source. However, in some cases no acceptable definition could be found and a new definition was prepared to define the object, term, or action. Attention has been given to defining specific robot types, coordinate systems, parameters, attributes, communication protocols and associated workstations and hardware. Diagrams are included to illustrate specific concepts that can best be understood by visualization. © 1994, IUPAC
Atmospheric Pressure Microwave Sample Preparation Procedure for the Combined Analysis of Total Phosphorus and Kjeldahl Nitrogen
Determination of Chromium Species in Dietary Supplements Using Speciated Isotope Dilution Mass Spectrometry with Mass Balance
Molecular Speciated Isotope Dilution Mass Spectrometric Methods for Accurate, Reproducible and Direct Quantification of Reduced, Oxidized and Total Glutathione in Biological Samples
Novel
protocols were developed to accurately quantify reduced (GSH),
oxidized (GSSG) and total (tGSH) glutathione in biological samples
using molecular speciated isotope dilution mass spectrometry (SIDMS).
For GSH and GSSG measurement, the sample was spiked with isotopically
enriched analogues of the analytes (<sup>310</sup>GSH and <sup>616</sup>GSSG), along with <i>N</i>-ethylmaleimide (NEM), and treated
with acetonitrile to solubilize the endogenous analytes via protein
precipitation and equilibrate them with the spikes. The supernatant
was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS),
and the analytes were quantified with simultaneous tracking and correction
for auto-oxidation of GSH to GSSG. For tGSH assay, a <sup>310</sup>GSH-spiked sample was treated with dithiothreitol (DTT) to convert
disulfide-bonded glutathione to GSH. After removing the protein, the
supernatant was analyzed by LC-MS/MS and the analyte was quantified
by single-spiking isotope dilution mass spectrometry (IDMS). The mathematical
relationships in IDMS and SIDMS quantifications are based on isotopic
ratios and do not involve calibration curves. The protocols were validated
using spike recovery tests and by analyzing synthetic standard solutions.
Red blood cell (RBC) and saliva samples obtained from healthy subjects,
and whole blood samples collected and shipped from a remote location
were analyzed. The concentrations of tGSH in the RBC and whole blood
samples were 2 orders of magnitude higher than those found in saliva.
The fractions of GSSG were 0.2–2.2% (RBC and blood) and 15–47%
(saliva) of the free glutathione (GSH + 2xGSSG) in the corresponding
samples. Up to 3% GSH was auto-oxidized to GSSG during sample workup;
the highest oxidations (>1%) were in the saliva samples