Isotope dilution method for the assay of rotenone in olive oil and river waters by liquid chromatography/multiple reaction monitoring tandem mass spectrometry

Abstract

A new approach for the assay of rotenone (1) by isotope dilution mass spectrometry is presented. The extreme toxicity of rotenone, a natural phytodrug with insecticidal and piscicidal activity, recently banned by national and international environmental protection agencies, calls for the development of sensitive and accurate methods of analyses. Accordingly, the proposed protocol is based on the availability of the labeled internal standard rotenone-d3 (3) which can be conveniently prepared by consecutive and specific mono-O-demethylation, and remethylation with methyl iodide-d3. The sensitivity of the method is confirmed by the very low limit of detection (LOD) and quantitation (LOQ) values achieved in the assay of 1 in two distinct fortified matrices, and is further supported by the observed accuracy values.

Assay of tyrosol and hydroxytyrosol in olive oil by tandem mass spectrometry and isotope dilution method

“…The method has been successfully applied to many important problems related to food safety and quality investigations (Di Donna, Maiuolo, Mazzotti, De Luca, & Sindona, 2004;Mazzotti, Di Donna, Attya, Gabriele, Fazio &Sindona, 2009;Mazzotti, Di Donna, Macchione, Maiuolo, Perri, & Sindona, 2009). The CID spectrum on the [MÀH] À species at m/z 153 obtained from 1, basically displays a single diagnostic fragment at m/z 123.0437, corresponding to the formal loss of a formaldehyde unit ( Figs.…”

A New Facile Synthesis of D4-Pterosin B and D4-Bromopterosin, Deuterated Analogues of Ptaquiloside

“…For the synthesis of d 4 -bromopterosin, the tetradeuterated alcohol was brominated directly using HBr in acetic acid [22], to give 2-(2-bromoethyl-1,1,2,2-d 4 )-1,3-dimethylbenzene (4b), which was subjected to a condensation reaction using methacrylic anhydride and polyphosphoric acid to give the final product d 4 -bromopterosin in a total yield of 91%. D 4 -ptetosin was also obtained with a total yield of 78% by the application of the same condensation reaction on d 4 -methoxypterosin 4a, followed by a demethylation reaction (Scheme 1) [23]. The proposed strategy demonstrates a new total synthesis for d 4 -bromopterosin and d 4 -pterosin.…”

Light and heavy dansyl reporter groups in food chemistry: amino acid assay in beverages

“…Accurate standardized methods for the simultaneous determination of AA in foods are required to assess their nutritional safety and compositional adequacy. The isotope dilution method, based on the combined use of mass spectrometry (MS/MS) and labeled internal standards, is a powerful tool for the assay of analytes in complex natural matrices, which has been successfully applied to many important problems related to food safety and quality assessment . A great improvement in both precision and accuracy of measurements is one of the many advantages achieved by applying this method, which minimizes problems arising from calibration procedure, sample preparation and matrix effects.…”