Determination and Confirmation of Organophosphate Pesticides and Their Metabolites in Beef Tissue Using Thermospray/LC-MS

• Published in: Journal of agricultural and food chemistry Vol. 42; no. 11; pp. 2619 - 2624
• Main Authors: Ioerger, Brian P, Smith, J. Scott
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.11.1994
• Subjects: Biological and medical sciences; CARNE DE RES; COMPOSE ORGANOPHOSPHORE; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; COMPUESTO ORGANICO DEL FOSFORO; ESPECTROMETRIA; ESPECTROMETRIA DE MASAS; Food industries; Fundamental and applied biological sciences. Psychology; Meat and meat product industries; METABOLITE; METABOLITOS; PESTICIDE; PLAGUICIDAS; RESIDU; RESIDUOS; SPECTROMETRIE; SPECTROMETRIE DE MASSE; TECHNIQUE ANALYTIQUE; TECNICAS ANALITICAS; VIANDE BOVINE; Adipose tissue; Metabolite; Pesticides; HPLC chromatography; Ox; Identification; Meat; Assay; Vertebrata; Mammalia; Residue; Analytical method; Lean body mass; Extraction; Muscle; Organophosphorus compounds; Artiodactyla; Mass spectrometry; Ungulata; Chemical contamination
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf00047a045

The ion formation characteristics of a group of organophosphate pesticides (OPs) and some of their primary and secondary metabolites were determined using a thermospray interface coupling a high-performance liquid chromatograph to a mass spectrometer (TSP/LC-MS). Full-scan mass spectra using a variety of ionization techniques, including filament-off, filament-on, and discharge-on, and two detection modes, positive ion (PI) and negative ion (NI), were collected for reference standards. A majority of the OPs and metabolites investigated produced ions in greatest abundance in the NI, discharge-on mode. Using a modification of a previously developed method, 17 OPs and metabolites were extracted from lean (4.1% fat) and fatty (29.3% fat) beef muscle. Recovery studies were performed at the 1 ppm fortification level in each sample type. Recoveries using negative ion TSP/LC-MS in the selected ion mode (SIM) ranged from 10 to 100+%. Response of the MS detector was linear over the 1-100 ppm concentration range for all detected compounds. Detection limits ranged between 1 and 5 ppm (20-100 ng injected). Five ions per compound were monitored in SIM, and their intensities were adequate for confirmation of compound identity