Vincent L. Maggio
Centers for Disease Control and Prevention
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Publication
Featured researches published by Vincent L. Maggio.
Journal of Chromatography B | 2002
Dana B. Barr; John R. Barr; Vincent L. Maggio; Ralph D. Whitehead; Melissa A. Sadowski; Robin M. Whyatt; Larry L. Needham
We have developed a sensitive and accurate analytical method for quantifying 29 contemporary pesticides in human serum or plasma. These pesticides include organophosphates, carbamates, chloroacetanilides, and synthetic pyrethroids among others and include pesticides used in agricultural and residential settings. Our method employs a simple solid-phase extraction followed by a highly selective analysis using isotope dilution gas chromatography-high-resolution mass spectrometry. Our method is very accurate, has limits of detection in the low pg/g range and coefficients of variation of typically less than 20% at the low pg/g end of the method linear range. We have used this method to measure plasma pesticide concentrations in females living in an urban area. We found detectable concentrations of carbaryl/naphthalene, propoxur, bendiocarb, chlorpyrifos, diazinon, dicloran, captan and folpet or their metabolites in more than 20% of the plasma samples tested.
Journal of Exposure Science and Environmental Epidemiology | 2001
John W. Brock; Yoshihiro Yoshimura; John R. Barr; Vincent L. Maggio; Sam R Graiser; Hiroyuki Nakazawa; Larry L. Needham
We report a new approach for assessing human exposure to bisphenol A (BPA) by measuring BPA in urine after enzymatic deglucuronidation. This method involves addition of 13C 12-labeled BPA, enzymatic deconjugation, solid-phase extraction, and derivatization with pentafluorobenzyl bromide. The product of the derivatization is separated by gas chromatography followed by mass spectrometric detection using negative chemical ionization and selected ion monitoring. Using this analysis method, urine samples fortified with both a constant level of labeled BPA and a range of unlabeled BPA levels (0.27–10.6 ng/ml) demonstrated constant percentage recovery. In addition, a range of urine sample volumes (0.25–10.0 ml) with constant amounts of added internal standard produced a linear response (r 2=0.99). The method limit of detection was 0.12 ng/ml. This method was validated by duplicate analyses using gas chromatography coupled to a high-resolution mass spectrometer.
Journal of Chromatography B | 2003
John R. Barr; Vincent L. Maggio; Dana B. Barr; Wayman E. Turner; Andreas Sjödin; Courtney D. Sandau; James L. Pirkle; Larry L. Needham; Donald G. Patterson
To increase our analytical throughput for measuring polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides without sacrificing data quality, we have developed and validated a combined PCB/OC pesticide gas chromatography-high-resolution mass spectrometry (GC-HRMS) analysis. In a single GC-HRMS analysis, both selected PCBs and OC pesticides are detected and quantified. Previously, this has been difficult, if not impossible, because of the major difference in masses of the most abundant electron-impact ions. However, we have identified slightly less abundant ions to monitor that allow us to successfully combine these analytes into a single analysis without sacrificing any analytical sensitivity or instrument reliability. Consequently, we have been able to double our analytical throughput by modification of mass spectrometric parameters alone. Our new methodology has been validated against our current GC-HRMS method, which entails using two separate injections, one for PCB analysis and one for OC pesticide analysis. The two methods differ by less than 4% overall, with no systematic bias. We used this method to analyze approximately 350 serum samples over a period of several months. We found that our new method was as reliable in automated, overnight runs as our current method.
Archives of Environmental Contamination and Toxicology | 1996
E. R. Barnhart; Vincent L. Maggio; L.R. Alexander; M. C. Reilly; L. T. Gelbaum; W. E. Turner; T. K. Hine; LarryL. Needham
Reversed-phase liquid chromatographic fractions of extracts of 2 preparations of eosinophilia-myalgia syndrome (EMS)-associated L-tryptophan were analyzed by proton nuclear magnetic resonance spectrometry, mass spectrometry, microbial-growth inhibition, and amino acid residue analyses. Fraction components demonstrated properties of an antibiotic peptide resembling bacitracin. Many peptide antibiotics like bacitracin are secondary metabolites of Bacillus species, genus of the tryptophan producer organism for the implicated manufacturer. In order to determine whether a correlation exists between individual EMS cases and the concentration of peptides or bacitracin consumed, reliable methods must be developed for quantification of the total of isoforms.
Clinical Chemistry | 1996
John R. Barr; Vincent L. Maggio; Donald G. Patterson; Gerald R. Cooper; L O Henderson; Wayman E. Turner; S J Smith; W H Hannon; Larry L. Needham; Eric J. Sampson
Environmental Health Perspectives | 1994
Donald G. Patterson; G D Todd; Wayman E. Turner; Vincent L. Maggio; L.R. Alexander; Larry L. Needham
Analytical Chemistry | 2003
Courtney D. Sandau; Andreas Sjödin; Mark D. Davis; John R. Barr; Vincent L. Maggio; Alyson Waterman; Kerry E. Preston; James Preau; Dana B. Barr; and Larry L. Needham; Donald G. Patterson
Journal of Analytical Toxicology | 2004
Carla E.A.M. Degenhardt; Kees Pleijsier; Marcel J. van der Schans; J.P. Langenberg; Kerry E. Preston; Maria I. Solano; Vincent L. Maggio; John R. Barr
Journal of Analytical Toxicology | 2008
Kerry E. Holland; Maria I. Solano; Rudolph C. Johnson; Vincent L. Maggio; John R. Barr
Journal of Analytical Toxicology | 2008
Maria I. Solano; Jerry D. Thomas; Jim Taylor; Jeffrey M. McGuire; Edward M. Jakubowski; Sandra A. Thomson; Vincent L. Maggio; Kerry E. Holland; J. Richard Smith; Benedict R. Capacio; Adrian R. Woolfitt; David L. Ashley; John R. Barr