Unit 1: Chemical Analysis

### What is toxicology? Definition…

the study of the adverse effects of chemicals or physical agents on living organisms.

### organic techniques = GC, HPLC, TLC, MS

GC = Gas chromatography, HPLC= High-Performance Chromatography , TLC= Thin Layer Chromatography and MS = MASS SPECTROMETRY.

### Inorganic techniques

### AES (ICP), AAS, NAA, X-Ray

### Retention Time of GC- definition?

Retention time (RT) is a measure of the time taken for a solute to pass through a chromatography column.

Examples of Stimulants:

Amphetamine, Cocaine and methamphetamine

Main of effects of stimulants on the body

are an intense feeling of pleasure, followed by a period of exhaustion and a prolonged period of depression. There’s also increased alertness and vigour.

Examples of Depressants:

Alcohol, Barbiturates and Tranquilizers.

Main effects of depressants on the body:

Depressants calm irritability and anxiety and may induce sleep.

### Screening test for marijuana?

The most common spot/colour test for marijuana is the Duquenois-Levine test, with Purple colour = + result.

### What is a lethal dose? (LD50)

LD50 refers to the dose of a substance that kills half the test population, usually within four hours. Testing is usually done on animals that compare well to humans’ metabolism.

### Symptoms of cyanide poisoning?

Seizures, Burnt almond odor

### Legal BAL in Ontario?

80 milligrams of alcohol in 100 millilitres of blood (0.08).

### Breathalyzers operate on→ IR spectrophotometry

The captured breath is exposed to infrared light. It’s the degree of the interaction of the light with alcohol in the captured breath sample that allows the instrument to measure a blood alcohol concentration in breath. Most of the breath-alcohol analyzers currently used for evidential purposes use ^^***infrared (IR) spectrometry.***

### Calculate BAL using formula→ GIVEN formula, but NOT what each value represents

BAC = 0.071(male) or 0.085(female) X vol consumed,oz X % alc divided by body weight

Organic analysis vs Inorganic analysis

In Organic Analysis, the matter is __**organic**__ (carbon atoms) vs In Inorganic analysis, the matter is __**inorganic**__ (no carbon atoms)

AAS (Inorganic analysis method)

Atomic Absorption Spectrometry: quantifies the absorption of electromagnetic radiation by well-separated neutral atoms.

AES (Inorganic analysis method)

Atomic Emission Spectrometry while atomic emission spectroscopy (AES) measures the emission of radiation from atoms in excited states.

X-rays (Inorganic analysis technique)

penetrate the crystal→ some reflected→ combine to form light and dark bands, known as __**diffraction patterns.**__ Every inorganic compound produces its own “fingerprint” of diffraction patterns.

NAA. (Inorganic analysis method)

Find trace elements in metals, drugs, paint, soil, gunpowder residue, and hair. Since this technique requires access to a nuclear reactor, however, it has limited value to forensic analysis.

Gas Chromatography (Organic analysis technique)

GC = Gas chromatography, ***mobile phase*** *(gas pushes sample through the column),* ***stationary phase*** *(liquid lines column) → final graph.*

High-Performance Chromatography (Organic analysis technique)

High-Performance Chromatography, ***mobile phase*** (liquid pushes sample through the column), ***stationary phase*** (solid particles lines column) → final graph.

Thin Layer Chromatography (Organic analysis technique)

Thin Layer Chromatography, ***stationary phase*** (sample placed on a solid coated plate), ***mobile phase*** (sample moves up plate) → separates into a pattern.

Mass Spectrometry (Organic Analysis technique)

In the mass spectrometer, they are detected electrically, in the mass spectrograph by photographic or other nonelectrical means. *Instead of shooting light through a substance (UV/IR spectrometry),* __***MS is shooting electrons.***__ ***Unique Feature→*** no two substances produce the same pattern.