Application of Mass Spectroscopy in Forensic Science

This presentation explains the principle of Mass Spectroscopy, a scientific method used to analyze the molecular makeup of a material. It focuses on the application of Mass Spectroscopy in Forensic Science, particularly in toxicological analysis, trace evidence, arson investigation, and analysis of explosives residue. The presentation also discusses the formation of cations and other fragments, the sorting of ions according to their mass to charge ratio, and the recording of the output as a mass spectrum. It concludes by highlighting the two general ways Mass Spectroscopy is used: to prove the identity of two compounds and to establish the structure of a new compound.

Mass Spectroscopy
By: [Name]
-These cations molecular or parent ion) are formed due to loss of an electron
usually from n or π orbital from a molecule, which can further break up into
smaller ions
-All these ions are accelerated by an electric field, sorted out according to their
mass to charge ratio by deflection in variable magnetic field and recorded. The
output is known as mass spectrum.
-Each line upon the mass spectrum indicates the presence of atoms or molecules
of a particular mass.
-The most intense peak in the spectrum is taken as the base peak. Its intensity is
taken as 100 and other peaks are compared with it.
Mass spectrum is used in two general ways:
-To prove the identity of two compounds.
-To establish the structure of a new a compound
Introduction
-Scientific method that analyzes a sample of
material to determine its molecular makeup in
terms of content and chemical properties
Principle
-Organic molecules
are bombarded
with a beam of
energetic electrons
(70 eV) in
gaseousstate under
pressure between
10-7 to 10-5 mm of
Hg,using tungsten
or rhenium
filament. Molecules
are broken up into
cations and many
other fragments
Application
-Use in forensic science to carry out toxicological
analysis, trace evidence, investigate arson, analysis of
explosives residue
-For example, Mass spectroscopy was applied in the 2004
Cameron Todd Willingham arson case in Texas US.

References
Sturler, A. d. (2015, March 28). Case of the Month: Forensic arson detection.
Retrieved from Defrosting Cold Cases: https://defrostingcoldcases.com/case-of-the-
month-forensic-arson-detection/
What Is Mass Spectroscopy Used for in Forensic Science? (2018). Retrieved from
Seattle: https://education.seattlepi.com/mass-spectroscopy-used-forensic-science-
6611.html