An HPLC/MS/MS method has been developed and validated for the quantification and confirmation of nicarbazin and ionophores (lasalocid, monensin, salinomycin, and narasin) in eggs. Nicarbazin is determined in the negative electrospray mode with a basic mobile phase that supports creation of negative ions. Consequently, our ability to maintain instrument sensitivity over time has significantly improved.
View Article and Find Full Text PDFEnviron Sci Technol
October 2009
Microcystins are bioactive metabolites produced by cyanobacteria in water. These cyclic heptapeptides have caused public health concern worldwide. By interfering with cellular phosphorylation and signaling, microcystins can cause acute and chronic liver diseases.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
October 2002
This paper describes a simple and efficient procedure for measuring 25 congeners of polychlorinated biphenyls in human milk. The limit of quantitation was 0.1 ng/ml for five less chlorinated congeners (PCB 70, 74, 87, 99,101), and 0.
View Article and Find Full Text PDFThis paper describes a simple procedure for the quantitative analysis of 25 polychlorinated biphenyl congeners (PCB) in serum. They are PCB 70, 74, 77, 87, 99, 101, 118, 126, 128, 138, 151, 153, 156, 169, 170, 180, 183, 187, 191, 194, 205, 206, 208 and 209. In addition, 15 pesticides are analyzed in the same extract: aldrin, p,p'-DDE, p,p'-DDT, dieldrin, endrin, endosulfan I, heptachlor, hexachlorobenzene, alpha-hexachlorocyclohexane, beta-hexachlorocyclohexane, lindane, methoxychlor, mirex, pentachlorobenzene, and 1,2,3,4-tetrachlorobenzene.
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