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TOF Analysis of Bay Water surrounding the Battleship Texas Presented at: SETAC 2013 South Regional Conference Work By: Sue D’Antonio, Joan Stevens, Andre Szczesniewski, Lynne Marshall, John Kimmel and Ken Helmreich
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Agilent 6230 TOF LC/MS TOF and QTOF techniques (non-target compounds) Identifies and differentiates compounds that were previously “hidden” under background Accurate mass TOF instruments: –Can determine empirical formula based on the mass of the compound in question (accurate mass) Novel data mining techniques Accurate Mass Databases, Mass Profile Processional Software Discover more compounds/contaminants, faster and with greater precision 6/27/2013
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API-TOF Ion Optical Design 6/27/2013 Page 3 API Ion Source Beam Shaper TOF Mass Analyzer Two Stage Ion Mirror Optically Coupled Ion Detector Effective Flight Path Length of 2.0m
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Formulae for TOF Performance 6/27/2013 Resolution = (m/z)/w 1/2 1000/0.1 = 10,000 922/0.087 = 10,597 Mass accuracy (mass error) (1000.001-1000.000)/1000)x10 6 =1 ppm Therefore: 1 ppm @ 1000 m/z is 0.001Da (1 mDa) 921.5922.0922.5923.0923.5924.0924.5 m/z, amu 923.0121 W 1/2 = 0.087 Epitestosterone Resolution 6890 meas = 289.2159 actual = 289.2162 -1.06 ppm 922.0092 6 10 actual - measured accuracy Mass
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How Much Accuracy is Needed? (Newer concept for LC/MS: ppm accuracy) Reserpine (C 33 H 40 N 2 O 9 ) has a protonated ion at 609.28066 Single quad reports mass to +/- 0.1 = 165 ppm Number of possible formulas using only C, H, O & N: 165 ppm209 10 ppm13 5 ppm7 3 ppm4 2 ppm2 Accurate mass reduces number of candidates and risk of investing effort with the wrong molecule 6/27/2013 Page 5
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SPE Sample Prep 6/27/2013 6
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Analysis of Water Samples 6/27/2013 9
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Choose Your Elements: Find Compounds by Molecular Feature and Generate Formulae 6/27/2013 10
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Molecular Feature Generator 6/27/2013 11
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Compound Chromatogram 6/27/2013 12
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Deductive Compound Choices 6/27/2013 13
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Conclusions Utilizing Agilent’s Time of Flight accurate mass, high resolution, superior isotopic fidelity and the unique features of Mass Hunter software, such as Molecular Feature Extractor and Molecular Formula Generator, we were able to identify over 100 compounds found in the samples. 6/27/2013 16
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