Applications of some hyphenated instrumentation in advanced forensic chemistry applications

1. ADVANCES IN FORENSIC CHEMISTRY
A SEMINAR PRESENTED
BY
INALEGWU, Telvin Omachi
BSU/SC/CHM/MSC/16/341
M. Sc .Analytical Chemistry
CHM 804: SEMINAR AND SELECTED READING
Department of Chemistry,
Benue State University, Makurdi.
26th July, 2018.
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2. CONTENTS
 Introduction
 Forensic Classification
 Tested samples
 Methods of Analysis
 Instruments
 Conclusion
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3. FORENSIC
• Forensic science is associated with the application of
analytical tool and technique in the discovery of evidence.
• Forensic chemistry is the study of detection and
identification of illicit drugs, toxics, accelerants used in
arson cases, explosives and gunshot residue
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4. Classification Based on
evidence
Chemical Biological Physical
Drugs and toxic
substances
Blood Fingerprints
Pigments/Pigments Body fluid Striations
Solvents Tissue Glass pieces
Explosives/Ballistics Plant derived
materials
Indentations(tire
impression)
Gunshot residue Saliva Tool mark
Resins, fibers, soil,
miscellaneous trace
evidence
Urine Questioned
documents
Alcohol(ethanol) Feather Plastic pieces.
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5. Classification Based on
Laboratory
• Based on
investigations
we have
Class I
Biology, Chemistry,
DNA and Toxicology
and Drugs lab
Class II
Fingerprint, Trace
evidence, Striation,
materials, Serology
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6. Tested samples
• There are two main classes of chemical
compounds:
• Organic compounds : • Are based on carbon
(containing the element carbon. • As a structural
backbone) and are found in living things.
• Inorganic compounds : • Are those based on
other elements.
• From the point of view of forensic science, both
organic and inorganic compounds are found in
items of evidence.
• The techniques used for determination of
chemical composition of such evidence often
depend upon whether the component compounds
are organic (derived form living tissue or material)
or inorganic.
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7. Methods of Analysis
• All methods are standard
methods.
• The selected methods
will be suitable for
• Lab samples.
• Reference for all
methods.
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8. • All the required instruments chosen
according to test methods:
GC/MS/RTL
LC/MS/TOF
mtDNA
LA/ICP/MS
microCT
DART-MS
LIBS
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9. GC/MS/RTL
• Gas Chromatography-Mass Spectroscopy with Retention Time
Locking.
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10. LC/MS/TOF
• Liquid Chromatography-Mass Spectroscopy Time of Flight
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11. mtDNA
• Electrophoretic Analysis of Mitochondrial DNA
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12. LA/ICP/MS
• Laser Ablation-Inductively coupled plasma-Mass
Spectroscopy
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13. microCT
• Micro-computer X-ray Tomography
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14. LIBS
• Laser Induced Breakdown Spectroscopy
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15. Conclusion
• the advanced electronics, material fabrication,software
design, and integration that these instruments
incorporate have enabled orders of magnitude
improvement in detection sensitivity, selectivity, and
analytical throughput. When these capabilities are
applied forensically, it enables a more subtle
discrimination and characterization of material
evidence. The new range of information extracted can
be crucial in validating, reducing uncertainty, or
conversely disproving theories employed in the
reconstruction of a chronology for the events under
investigation and thereby help ensure that a correct
finding results.
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