Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: KEGG:D04839 (Florisil)
 775 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Isopropylthioxanthone (ITX) has been widely used as the photoinitiator in printing ink of packaging materials in modern food packaging industry. A method regarding the identification and qualification of ITX residue in milk migrated from food contact packaging materials was developed. The procedure was based on the gas chromatography-mass spectrometry (GC-MS) for screening and gas chromatography-tandem mass spectrometry (GC-MS/MS) for confirmation after a solid phase extraction (SPE) step using Florisil column with anthracene D10 (AD10) as the internal standard. Data was acquired in selective ion monitoring (SIM) mode with the following ions: m/z 184, m/z 224, m/z 239, m/z 254 for ITX and m/z 80, m/z 94, m/z 188, m/z 160 for AD10 in screening method of GC-MS. The m/z 254 was selected as the parent ion and m/z 239 as the daughter ion in the conformation method of GC-MS/MS. Data acquired employed the transition of m/z 254, m/z 239 for ITX and m/z 188, m/z 160 for AD10. The method gave limits of quantification (LOQ) of 7.0 microg/L (GC-MS) and 5.0 microg/L (GC-MS/MS) respectively as well as recoveries ranged from 74.9% to 89.6%. The analysis of real samples found two positives out of 11 different milk stuffs available using this method.
 ...
PMID:[Determination of isopropylthioxanthone residue in milk migrated from packaging materials by gas chromatography-mass spectrometry]. 1743 73

A sensitive, accurate and simple liquid chromatography coupled with mass spectrometry method for the determination of 10 selected pesticides in soya beans has been developed and validated. The method is intended for use during the characterization of selected pesticides in a reference material. In this process, high accuracy and appropriate uncertainty levels associated to the analytical measurements are of utmost importance. The analytical procedure is based on sample extraction by the use of a modified QuEChERS (quick, easy, cheap, effective, rugged, safe) extraction and subsequent clean-up of the extract with C18, PSA and Florisil. Analytes were separated on a C18 column using gradient elution with water-methanol/2.5 mM ammonium acetate mobile phase, and finally identified and quantified by triple quadrupole mass spectrometry in the multiple reaction monitoring mode (MRM). Reliable and accurate quantification of the analytes was achieved by means of stable isotope-labelled analogues employed as internal standards (IS) and calibration with pure substance solutions containing both, the isotopically labelled and native compounds. Exceptions were made for thiodicarb and malaoxon where the isotopically labelled congeners were not commercially available at the time of analysis. For the quantification of those compounds methomyl-(13)C2(15)N and malathion-D10 were used respectively. The method was validated according to the general principles covered by DG SANCO guidelines. However, validation criteria were set more stringently. Mean recoveries were in the range of 86-103% with RSDs lower than 8.1%. Repeatability and intermediate precision were in the range of 3.9-7.6% and 1.9-8.7% respectively. LODs were theoretically estimated and experimentally confirmed to be in the range 0.001-0.005 mg kg(-1) in the matrix, while LOQs established as the lowest spiking mass fractionation level were in the range 0.01-0.05 mg kg(-1). The method reliably identifies and quantifies the selected pesticides in soya beans at appropriate uncertainty levels, making it suitable for the characterization of candidate reference materials.
 ...
PMID:Accurate determination of selected pesticides in soya beans by liquid chromatography coupled to isotope dilution mass spectrometry. 2577 Jun 14