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Mass Spectrometry in Forensic Science

Mass Spectrometry in Forensic Science. Erin Shonsey March 16, 2011. Overview. Introduction to forensic sciences Uses of mass spectrometry in forensic sciences Typical instrumentation in forensic sciences Applications of new instrumentation. Introduction to Forensic Sciences.

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Mass Spectrometry in Forensic Science

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  1. Mass Spectrometry in Forensic Science Erin Shonsey March 16, 2011

  2. Overview • Introduction to forensic sciences • Uses of mass spectrometry in forensic sciences • Typical instrumentation in forensic sciences • Applications of new instrumentation

  3. Introduction to Forensic Sciences Forensic Sciences is defined as: the application of a broad spectrum of sciences to answer questions of interest to the legal system.

  4. Introduction to Forensic Sciences Typical analytical sections within a forensic science laboratory: Drug Chemistry – Analysis of pills, powders, liquids, plant materials, and other suspicious items for illegal drug content Toxicology – Analysis of biological samples for alcohol, prescription medication, drugs of abuse, and other chemicals that are not naturally occurring in the body DNA – Extraction and amplification of DNA from biological fluids for identification Firearms – Bullet pattern recognition and analysis of gun powder Fire Debris -- Identification of ignitable liquids used in arsons

  5. Standards for Accepting the Scientific Validity of a Procedure, Technique, and Principle • Alabama • Frye standard: the court must decide if the questioned procedure, technique, and principles are “generally accepted” by a relevant community • Federal Rule 702: a witness qualified as an expert may testify in the form of an opinion • Federal • Daubert: • Has it been tested? • Has it been published and peer reviewed? • Potential rate of error • Existence and maintenance of standards controlling the techniques operation • Accepted in the relevant scientific community

  6. Mass Spectrometry in Forensic Science A gas chromatograph with a mass spec detector is the final tool used in the analysis of drug chemistry and toxicology samples for identification and confirmation.

  7. Typical forms of Mass Spectrometry in Every Forensic Science Lab Gas Chromatography-Mass Spectrometry (GC-MS) http://www.chem.arizona.edu/massspec/intro_html/intro.html

  8. Typical forms of Mass Spectrometry in Every Forensic Science Lab Gas Chromatography-Mass Spectrometry (GC-MS) http://www.microbialcellfactories.com/content/figures/1475-2859-6-6-4-l.jpg

  9. Typical forms of Mass Spectrometry in Every Forensic Science Lab

  10. Typical forms of Mass Spectrometry in Every Forensic Science Lab Gas Chromatography-Mass Spectrometry (GC-MS) Spectrum Spectra are searched against a library of known compounds in an effort to identify every peak in the TIC A standard is analyzed on the instrument to generate a known retention time and spectrum of the compound for that instrument

  11. Problems Encountered with the GC/MS Lose the parent ion of the compound upon ionization in the instrument Example: Methadone

  12. Problems Encountered with the GC/MS Derivatize the compound for analysis with GC/MS which decreases detection of low level compounds Example: THC

  13. Problems Encountered with the GC/MS Heat labile compound will be identified as a related compound, but not the actual compound Example: Clorazepate to Nordiazepam

  14. New Technology • Four new instruments have been brought into the department in October 2008 • AccuTOF-DART mass spectrometer • 3200 QTRAP mass spectrometer with LC • 3200 QTRAP mass spectrometer with DART • HS-GC-MSD

  15. Different forms of Mass Spectrometry N2 Collision gas Gas Sample solution - - - - - - - - - + + - - -5 KV Detector Q1 Q2 Q3 Atmospheric pressure Vacuum Liquid Chromatography Electrospray Ionization Mass Spectrometry (LC-ESI-MS)

  16. Different forms of Mass Spectrometry Direct Analysis in Real Time with Time of Flight Mass Spectrometry N 2 TOF detector Electrostatic reflector

  17. HS-GC-MSD • This instrument provides opportunity for qualitative and quantitative identification of volatile compounds

  18. TIC of Volatiles Mix

  19. Spectrum of Peak at 1.44 min Isopropanol

  20. Spectrum of Peak at 1.61 min Acetone

  21. Spectrum of Peak at 1.70 min 1-propanol (IS)

  22. TIC of Ethanol Standard

  23. Spectrum of Peak at 1.29 min Ethanol

  24. Spectrum of Peak at 1.70 min 1-propanol (IS)

  25. Summary • Method development is underway with the HS-GC-MSD • Good separation and spectra from the volatiles mix and ethanol standard • Ready to start validation • Developing method for commonly abused inhalants • Developing a screening for other volatile compounds • Example: GHB

  26. The DART is the first open air, ambient ion source for a mass spectrometer Coupled to a time of flight instrument exact mass measurements can be used in the putative identification of compounds AccuTOF-DART MS

  27. Coupled to a hybrid triple quadrupole/Trap instrument molecular ions can be individually fragmented for identification of sample components 3200 QTRAP-DART MS

  28. DART Ionization Penning ionization: energy is transferred from metastable ions (M*) Positive ions: He* ionizes water which transfers a proton to the sample Negative ions: Penning electrons are rapidly thermalized and captured by oxygen which ionizes the sample http://www.jeolusa.com/PRODUCTS/AnalyticalInstruments/MassSpectrometers/AccuTOFDART/AccuTOFDARTIonizationMechanisms/tabid/450/Default.aspx

  29. DART Ionization M M M M H2O MH+ [(H2O+)nH]+ H2O MH+ MH+ H2O He* He He* H2O [(H2O+)nH]+ He He He* He* He* H2O He* H2O He He He* He* MH+ MH+ He* He* He* He He He* He [(H2O+)nH]+ He H2O H2O MH+

  30. Accelerating pulse Time of Flight Detector TOF detector t = (d/√(2U))((√m/z)) t = time d = flight tube distance U = accelerating voltage m = mass z = charge

  31. AccuTOF Mass Spectrometer N 2 Repelling plate Orthogonal acceleration time of flight TOF detector The reflector doubles the length of the flight tube Electrostatic reflector

  32. Different forms of Mass Spectrometry DART Ionization Tandem Mass Spectrometry N2 Collision gas Detector Q1 Q2 Q3 Vacuum

  33. m1 m4 m1 m4 m1 m4 Quadrupoles have variable ion transmission modes m2 m3 m2 m3 mass scanning mode m2 m2 m2 m2 m2 m3 single mass transmission mode

  34. Molecular Ion Scanning N2 Detector Q1 Q2 Q3 Vacuum

  35. Product Ion Scanning Collision gas N2 N2 N2 N2 N2 N2 Detector Q1 Q2 Q3 Vacuum

  36. Multiple Reaction Monitoring (MRM) Collision gas N2 N2 N2 N2 N2 N2 Detector Q1 Q2 Q3 Vacuum

  37. Sample Introduction with the AccuTOF-DART MS Liquid samples are introduced with a glass capillary tube closed at one end Solid samples are introduced into the stream with tweezers

  38. Sample Introduction with the AccuTOF-DART MS Every sampling device is analyzed for contamination prior to use 3 x 10 Intensity ( 1696474 ) 1 . 46 1 . 58 1500 0 . 85 0 . 40 1 . 15 1 . 03 1000 0 . 30 1 . 37 500 1 . 36 0 . 18 1 . 17 0 0 . 2 0 . 4 0 . 6 0 . 8 1 . 0 1 . 2 1 . 4 1 . 6 Time [ min ]

  39. Types of Samples Analyzed with the AccuTOF-DART MS http://www.ecstasy2.com/img/ecstasy_pill_collage1.jpg

  40. White Powder Analyzed with the AccuTOF-DART MS 3 x 10 Intensity ( 16873 ) 150 . 13 10 192 . 14 152 . 15 0 50 100 150 200 250 300 350 400 450 500 m / z Name Neutral comp. Meas. Calc. Diff(u) Abund. Methamphetamine C10H15N 150.1302 150.1283 0.0020 100.0000 Phentermine C10H15N 150.1302 150.1283 0.0020 100.0000 Amantadine C10H17N 152.1460 152.1439 0.0020 21.3243 Phendimetrazine C12H17NO 192.1422 192.1388 0.0034 21.6783

  41. Molecular Ion Mass Spectrum Possible Methamphetamine 150.3 2.8e6 2.6e6 2.4e6 2.2e6 Q1 of White Powder 2.0e6 1.8e6 1.6e6 Intensity, cps 1.4e6 1.2e6 1.0e6 210.3 192.3 8.0e5 121.2 152.3 166.3 6.0e5 234.3 284.3 299.4 4.0e5 366.4 252.4 315.4 263.4 168.2 312.4 180.3 154.3 212.3 256.2 2.0e5 292.4 194.2 226.3 317.3 334.4 342.5 382.4 78.1 279.4 232.3 354.4 138.2 131.4 386.4 117.3 0.0 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 m/z, Da

  42. Product Ion Mass Spectrum 91.0 2.1e5 2.0e5 1.9e5 1.8e5 1.7e5 1.6e5 1.5e5 1.4e5 1.3e5 1.2e5 1.1e5 Intensity, cps 1.0e5 9.0e4 8.0e4 7.0e4 6.0e4 5.0e4 4.0e4 3.0e4 2.0e4 119.1 1.0e4 150.1 0.0 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 m/z, Da

  43. 5500 5000 Total Analysis Time = 5 min 4500 4000 3500 3000 Intensity, cps 2500 2000 1500 1000 500 0 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 Time, min

  44. Plant Material Analyzed with the AccuTOF-DART MS 3 x 10 Intensity ( 110649 ) 315 . 23 100 316 . 23 205 . 20 0 50 100 150 200 250 300 350 400 450 500 m / z Name Neutral comp. Meas. Calc. Diff(u) Abund. Cannabidiol C21H30O2 315.2355 315.2324 0.0031 100.0000 Tetrahydrocannibinols C21H30O2 315.2355 315.2324 0.0031 100.0000

  45. 193.2 4.8e5 4.6e5 4.4e5 4.2e5 4.0e5 3.8e5 123.1 3.6e5 3.4e5 3.2e5 3.0e5 2.8e5 2.6e5 81.1 Intensity, cps 2.4e5 2.2e5 93.1 2.0e5 1.8e5 107.1 135.2 1.6e5 69.1 1.4e5 109.2 1.2e5 1.0e5 259.2 8.0e4 43.1 6.0e4 231.3 137.1 121.1 217.1 177.2 79.0 4.0e4 315.3 67.1 91.1 207.2 235.2 165.1 105.1 247.1 111.1 151.1 221.4 55.1 161.2 2.0e4 191.3 189.2 96.8 0.0 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 m/z, Da

  46. 0.33 6.3e4 6.0e4 Total Analysis Time = 5 min 5.5e4 5.0e4 0.21 4.5e4 4.0e4 3.5e4 Intensity, cps 3.0e4 2.5e4 2.0e4 1.5e4 1.0e4 5000.0 0.0 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 Time, min

  47. Clandestine Tablet Analyzed with the AccuTOF-DART MS 3 x 10 Intensity ( 174735 ) 177 . 14 231 . 11 100 195 . 09 0 50 100 150 200 250 300 350 400 450 500 m / z Name Neutral comp. Meas. Calc. Diff(u) Abund. Benzylpiperazine C11H16N2 177.1409 177.1392 0.0017 100.0000 Caffeine C8H10N4O2 195.0891 195.0882 0.0009 33.0937 TFMPP C11H13F3N2 231.1119 231.1109 0.0010 69.6525

  48. 91.1 2.0e5 1.9e5 1.8e5 1.7e5 1.6e5 1.5e5 1.4e5 1.3e5 1.2e5 1.1e5 Intensity, cps 1.0e5 9.0e4 8.0e4 7.0e4 6.0e4 5.0e4 4.0e4 3.0e4 2.0e4 177.2 85.0 1.0e4 56.0 0.0 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 m/z, Da

  49. 7.8e4 7.5e4 7.0e4 Total Analysis Time for 2 Items = 8 min Analyst Time for 2 Items = 3 hrs 6.5e4 6.0e4 5.5e4 5.0e4 4.5e4 4.0e4 Intensity, cps 3.5e4 3.0e4 2.5e4 2.0e4 1.5e4 1.0e4 5000.0 0.0 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 Time, min

  50. Clandestine Tablet Analyzed with the AccuTOF-DART MS 3 x 10 Intensity ( 31002 ) 30 177 . 14 147 . 11 150 . 13 20 257 . 25 10 194 . 12 231 . 11 116 . 14 285 . 28 0 50 100 150 200 250 300 350 400 450 500 m / z Name Neutral comp. Meas. Calc. Diff(u) Abund. Phentermine C10H15N 150.1277 150.1283 -0.0005 68.2766 Methamphetamine C10H15N 150.1277 150.1283 -0.0005 68.2766 Benzylpiperazine C11H16N2 177.1400 177.1392 0.0008 100.00 Butamben C11H15NO2 194.1187 194.1181 0.0006 21.7282 MDMA C11H15NO2 194.1187 194.1181 0.0006 21.7282 TFMPP C11H13F3N2 231.1117 231.1109 0.0008 12.8296

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