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

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Presentation on theme: "Mass Spectrometry in Forensic Science Erin Shonsey March 16, 2011."— Presentation transcript:

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.sciences

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 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 Standards for Accepting the Scientific Validity of a Procedure, Technique, and Principle

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)

8 Typical forms of Mass Spectrometry in Every Forensic Science Lab Gas Chromatography-Mass Spectrometry (GC-MS)

9 Typical forms of Mass Spectrometry in Every Forensic Science Lab

10 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 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 Electrostatic reflector TOF detector

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

18 TIC of Volatiles Mix

19 Isopropanol Spectrum of Peak at 1.44 min

20 Acetone Spectrum of Peak at 1.61 min

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

22 TIC of Ethanol Standard

23 Ethanol Spectrum of Peak at 1.29 min

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

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 AccuTOF-DART MS 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

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

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 onMechanisms/tabid/450/Default.aspx

29 He* He He* He H2OH2O H2OH2O H2OH2O H2OH2O He* [(H 2 O + ) n H] + M M M M MH + H2OH2O H2OH2O H2OH2O H2OH2O He*MH + DART Ionization

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

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

32 Q1 Q2Q3 Detector Collision gas N2N2 Vacuum Different forms of Mass Spectrometry DART Ionization Tandem Mass Spectrometry

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

34 Q1 Q2Q3 Detector N2N2 Vacuum Molecular Ion Scanning

35 Q1 Q2Q3 Detector Collision gas N2N2 Vacuum N2N2 N2N2 N2N2 N2N2 N2N2 Product Ion Scanning

36 Q1 Q2Q3 Detector Collision gas N2N2 Vacuum N2N2 N2N2 N2N2 N2N2 N2N2 Multiple Reaction Monitoring (MRM)

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 Time[min] Intensity( )x

39 Types of Samples Analyzed with the AccuTOF-DART MS

40 White Powder Analyzed with the AccuTOF-DART MS Name Neutral comp. Meas. Calc. Diff(u) Abund. Methamphetamine C10H15N Phentermine C10H15N Amantadine C10H17N Phendimetrazine C12H17NO

41 Q1 of White Powder m/z, Da e5 4.0e5 6.0e5 8.0e5 1.0e6 1.2e6 1.4e6 1.6e6 1.8e6 2.0e6 2.2e6 2.4e6 2.6e6 2.8e6 Intensity, cps Possible Methamphetamine Molecular Ion Mass Spectrum

42 NameFitRevFitPurityCE METHAMPHETAMINE BZP PHENTERMINE METH-TPC METH-TPC TFMPP Metanephrine Product Ion Mass Spectrum

43 METHAMPHETAMINE 1METHAMPHETAMINE 2RATIO% OF STANDARD STANDARD CASE % Total Analysis Time = 5 min

44 m/z Intensity(110649)x Plant Material Analyzed with the AccuTOF-DART MS Name Neutral comp.Meas. Calc. Diff(u) Abund. Cannabidiol C21H30O Tetrahydrocannibinols C21H30O

45 NameFitRevFitPurityCE THC MDMA BZP MDMA MDMA TFMPP Phenobarbitol PSEUDOEPHEDRINE METHAMPHETAMINE Epinephrine Normetanephrine Metanephrine Epinephrine Metanephrine

46 THC 1THC 2RATIO% OF STANDARD STANDARD2.49E E CASE1.11E E % Total Analysis Time = 5 min

47 Name Neutral comp. Meas. Calc. Diff(u) Abund. Benzylpiperazine C11H16N Caffeine C8H10N4O TFMPP C11H13F3N Clandestine Tablet Analyzed with the AccuTOF-DART MS m/z Intensity(174735)x

48 NameFitRevFitPurityCE BZP METHAMPHETAMINE PHENTERMINE METH-TPC

49 BZP 1BZP 2RATIO% OF STANDARD STANDARD1.51E E CASE Item #14.66E E % CASE Item #26.21E E % Total Analysis Time for 2 Items = 8 min Analyst Time for 2 Items = 3 hrs

50 Name Neutral comp. Meas. Calc. Diff(u)Abund. Phentermine C10H15N Methamphetamine C10H15N Benzylpiperazine C11H16N Butamben C11H15NO MDMA C11H15NO TFMPP C11H13F3N Clandestine Tablet Analyzed with the AccuTOF-DART MS

51 NameFitRevFitPurityCE MDMA METHAMPHETAMINE BZP PHENTERMINE Warfarin PSEUDOEPHEDRINE Epinephrine THC Normetanephrine METH-TPC Lorazepam Milrinone Epinephrine NameFitRevFitPurityCE METHAMPHETAMINE BZP PHENTERMINE METH-TPC METH-TPC TFMPP Metanephrine NameFitRevFitPurityCE BZP METHAMPHETAMINE PHENTERMINE METH-TPC

52 METHAMPHETAMINE 1METHAMPHETAMINE 2RATIO% OF STANDARD STANDARD CASE % MDMA 1MDMA 2RATIO% OF STANDARD STANDARD CASE % BZP 1BZP 2RATIO% OF STANDARD STANDARD CASE % Analysis Time = 10 min

53 m/z 0 20 Intensity(33499x m/z Intensity( Methamphetamine (Pseudo)ephedrine Clandestine Laboratory Samples Analyzed with the AccuTOF- DART MS Pen tube Aluminum Foil

54 m/z Intensity(50970)x m/z Intensity(182939)x m/z 0 50 Intensity(72800)x Blender Jar White Powder Aluminum Foil Methamphetamine (Pseudo)ephedrine

55 m/z Intensity(57470)x m/z 0 50 Intensity(98301)x Methamphetamine (Pseudo)ephedrine Rubber Tubing White Powder

56 NameFitRevFitPurityCE PSEUDOEPHEDRINE METHAMPHETAMINE BZP Metanephrine Epinephrine Normetanephrine Epinephrine PHENTERMINE Normetanephrine MDMA TFMPP Milrinone Phenobarbitol Warfarin Warfarin METH-TPC Metanephrine

57 PSEUDO 1PSEUDO 2RATIO STANDARD5.75E E White Powder5.17E E % White Powder4.08E E % Pen Tube5.75E E % Blender5.94E E % Clandestine Laboratory Samples Analyzed with the DART- QTRAP Total Analysis Time for 7 Items = 1 hr Analyst Time for 7 Items = 2 days METHAMPHETAMINE 1METHAMPHETAMINE 2RATIO% OF STANDARD STANDARD2.78E E White Powder1.51E E % Pen Tube6.85E E % Aluminum Foil9.25E E % Aluminum Foil3.02E E % Rubber Tubing7.89E E %

58 Efficient screening instrument –Soft ionization keeps the molecular ion intact Mass accuracy allows matches within 5 mmu of the theoretical mass of a compound –No extraction is required for sample analysis Raw samples the preferred sample –High-throughput Typical analysis time for a sample is 1-2 min Real Time Sample Analysis with the AccuTOF- DART MS

59 Compound fragmentation is possible without extraction CID fragmentation allows retention of molecular ion in fragmentation spectrum –These can be searched against an in house library for identification MRM analysis gives ion ratios for a second level of compound identification in comparison to a standard Complex mixtures do not present a problem for analysis –The instrument has the ability to isolate a single compound for fragmentation Real Time Sample Analysis with the DART- QTRAP MS

60 LC-MRM-MS assay for Drug Detection and Quantitation

61 LC-ESI-MS/MS Spectrum of Methadone

62 LC-MRM-MS analysis for Drug Quantitation Q1Q2Q3 Collision gas

63 Q1Q2Q3 Collision gas LC-ESI-MRM-MS Compound Molecular Weight Parent ion Product ion Dwell Time (msec) Declustering Potential (DP) Collision Energy (CE) Retention TimepKa Alprazolam Amitriptyline Cocaethylene Cocaine Fentanyl Imipramine Mepivacaine Methadone Methamphetamine Oxycodone THC Trazodone

64 Time, min TIC of Check Mix Retention Order Oxycodone Methamphetamine Mepivacaine Cocaine Cocaethylene Trazodone Fentanyl Imipramine Methadone Amitriptyline Alprazolam THC

65 Survey Scan (1) Second Dependent Scan (s) IDA Criteria Level 1 Survey Scan (2) Dependent Scan (s) Enhanced Resolution Add to Exclusion List Survey scan be EMS, EMC, Neutral Loss, Precursor Scan, MRM or EPI (combinations of 2 surveys) Improve Resolution/Accuracy Inclusion/Exclusion List Second Level Dependant Scan (MS 3 ) IDA Criteria Level 2 Dependent Scan (s) Second Dependent Scan (s) Two levels of criteria Multiple dependant scans (EPI, Product Ion and MS3) Information Dependent Acquisition (IDA) Courtesy of Ricky Ciner

66 IDA Analysis of Check Mix TIC XIC MRM EPI

67 Library Search of Fragment Spectrum

68 Summary LC-ESI-MS can be used in the qualitative and quantitative analysis of drugs in toxicological specimens –The instrumentation is advantageous in that chemicals do not have to be derivatized –The soft ionization aids detection of the parent ion of the compound

69 Overall Summary Mass spectrometry is a powerful tool in a forensic science lab New instrumentation is expanding the sample analysis possibilities beyond current limitations No one technique is robust enough for everything, therefore a combination of techniques is ideal for screening and confirmation of drug and toxicology samples

70 Acknowledgements UAB Dr. Stephen Barnes Marion Kirk Ray Moore Dr. Matthew Renfrow Landon Wilson ADFS Dr. Dale Carpenter Andrea Headrick Dr. Jack Kalin Gary Wallace


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