Description

Chemistry Connections

Episode #2

Welcome to Chemistry Connections, my name is EMILY GREENBERG and I am your host for episode #2 called The chemistry behind forensics. Today I will be discussingthe chemistry behind forensic science and crime scene investigation.

Segment 1: Introduction to forensics

Forensic science is the tests and techniques used in the detection of crime. Forensic scientists use the scientific method to solve crimes.

They collect data and evidence from crime scenes and analyze it to try to figure out the manner and the perpetrator of a crime. 

Analysis of blood or fingerprints left at a crime scene are very important in identifying a victim or a suspect. Clothing fibers, ink, ash, and much more can also be used in forensics to detect and solve crimes.

Forensic science is one of the most critical aspects of the criminal justice system because it involves hard evidence and can be proven.

Forensics are so important because they can help rule out manners of death and can find suspects for different crimes.

Segment 2: The Chemistry Behind forensics

Chemistry is one of the most important aspects of forensics. The following methods are the most important chemical experiments that are used in forensics.

Chromatography: This is a process where chemists use heat to separate mixtures into different contents so they can determine the individual components of a mixture. There are many different types of chromatography which will be described in this episode. 

TLC (thin layer chromatography) is a less complex type of chromatography. 

• Used to analyze inks and dyes of fibers left at a crime scene and can help a forensic scientist match a fiber to a specific company if differences between fibers are very small

Gas Chromatography is used for volatile liquids

• Often used to separate and analyze blood left at a crime scene. This can determine if the victim or suspect had alcohol or drugs in their system.
• Can be used to investigate cases of arson and can detect if an accelerant is used. This can be used to see whether a fire was intentional or not 
• Mass spectrometry is used as a detector by detecting the concentration of the substance 

HPLC (High performance liquid chromatography) extracts individual components from a solution

• HPLC is used for nonvolatile mixtures
• A common detector for this type of chromatography is called an ultraviolet visible spectrometer 
• This is used for drug analysis because most pharmaceuticals have UV absorbance