FORENSIC CHEMISTRY
- Overview
- Assessment methods
- Learning objectives
- Contents
- Full programme
- Bibliography
- Teaching methods
- Contacts/Info
A basic familiarity with the molecular structures of organic and inorganic substances and with the simplest and most common analytical methods (spectroscopic and non-spectroscopic) is a fundamental prerequisite. Different types of scientific investigation will be shown in the illustration of the most diverse forensic fields.
The final exam will be divided into two parts: a written test will be held on the program illustrated during the course and with a test based on open questions and specific questions. In addition, each student will show a final presentation on a forensic study based on a scientific publication chosen by the student from a scientific journal of the sector. The written exam will contribute to the final vote with a weight of 80%, while the remaining 20% will be defined by the judgment on the presentation.
The course, after a brief illustration and historical introduction on forensic sciences, aims to illustrate different types of techniques used in the field of broad-spectrum forensic investigations. We plan to illustrate different and multiple applications of different analytical methods in cases that are more subject to investigations involving legal interventions. The field of study will have as its object chemical techniques, but not only and also other disciplines that mainly involve a study at the molecular level. The techniques that will be illustrated will be accompanied by some examples of forensic investigation applications.
Historical introduction to forensic sciences and in particular to forensic chemistry. Disciplines in the field of criminology and crime. Scientific method. The main contents of the course program focus on different aspects and different matrixes that can be investigated and investigated. Techniques for collecting fingerprints and different fingerprinting techniques will be illustrated. Reagents that allow the imprint to be highlighted will be illustrated. Analysis of substances of abuse and markers to determine the type of clandestine production. Historical development of different tests for the recognition of ethyl abuse. Analysis and dating of human remains: forensic entomology and other techniques for calculating the onset of death. DNA analysis. STR and PCR analysis. Use of DNA-associated techniques in different types of analysis: guilt or innocence and determination of parental lines. Nuclear DNA and mitochondrial DNA.
Doping substances and analysis using WADA methodologies. Recognition of doping substances by GC-MS and HPLC-MS. Fire and explosion analysis. Organic and inorganic explosives. Analysis of shot residues. Analysis of the different types of matrices (hair, fibers, blood, urine, organic liquids, etc.). Qualitative analysis by spot test. The problem of false positives. Analysis of biological fluids with particular interest and relief for the blood and its components. Presumptive tests and confirmatory tests for the presence of traces of blood. Blood grouping methods.
Historical introduction to forensic chemistry and forensic sciences. Origin of forensic disciplines in literature. Criminology and criminal law. Scientific method in forensic analysis. First examples of Forensic scientists. First steps of forensic science. Search for poisons. Blood research. Poison analysis. Marsh test. Locard principle. Different matrices object of analysis. Use of spot tests. Probability of false positives.
What are the footprints. How to distinguish and classify them. Main types of footprints. First discoveries and identification of fingerprints as a means of recognizing a subject. Minutiae and particular elements of an impression. Identification of points and different legislation for the assignment of an unknown footprint to a person. Visible, plastic and latent impressions. Recognition systems. Chemical composition of a fingerprint. Methods for highlighting impressions: powders, chemical reagents and optical methods. Impression powders: composition and materials used for their preparation. Factors that influence the effectiveness of a powder to define a footprint. SPR and VMD methods. Fingerprint quality. Chemical tests: silver nitrate, ninhydrin, iodine, cyan acrylate, physical developer and ruthenium oxide. Other reagents used for research and evidence of fingerprints. Reactive for coloring the impressions and for the best visualization. Special cases: relief of bullet and cartridge cases. Use of alternating light sources. Forensic torches. Literature articles and recent publications on footprints.
Blood chemistry. Blood composition. Serology and distinctions between blood groups. Agglutination phenomenon. Hemoglobin. Test with peroxides. Guaiac test. Presumptive tests for the presence of traces of blood. Chemiluminescence and use of Luminol. Possibility of investigations leading to false positives and misleading results. Fluorescein test. Benzidine test. Other blood tests: Kastle-Meyer, green Lucomalachite, tetramethylbenzidine. Bluestar, an improved form of the Luminolo. Confirmatory tests of Takayama and Teichmann. Precipitous test. Capillary test, diffusion gel and electrophoresis. Determination of the human nature of blood. Analysis of bloodstains and shape of bloodstains as findings of a crime. Impact angles and size of blood spots. Algor mortis, rigor mortis and livor mortis determined by the blood present in an organism and in the different tissues. Seminal fluid and saliva analysis. Acid phosphatase test. Classification of enzymes. Analysis with naphthylphosphate. PSA analysis. Choline and spermine test. Barberio test. Test with amylase. Classification of blood groups according to AB0 mode. Antigens and antibodies in the determination of blood groups. Molecular distinction of the different blood groups. Rhesus factor (Rh factor). Other types of classification of blood groups (MNS, Lutheran, Kell, Lewis, Duffy, Kidd, Diego, Cartwright, Xg and Scianna). Isoenzymes and surface proteins of red blood cells. Blood groups in hereditary traits. Human leukocyte antigens. Literature articles and recent publications on blood and forensic serology.
Arson and explosions in the context of forensic investigations. Statistics and frequency data related to malicious events in which explosions and fires occur. Substances known as flame accelerators. Combustion process. Combustion heat. The triangle of fire. The fire tetrahedron. Ignition temperature and flash point of different chemicals. V-stains as fire residues. Accelerator research methods: colorimetric chemical tests, catalytic combustion detectors, flame ionization detectors, ultraviolet fluoroscopes and infrared spectrometers. Griess test. Flame accelerator extraction processes: steam distillation, vacuum distillation, solvent extraction, activated carbon sampling and headspace sampling. Investigations on forensic analysis in the field of explosives and criminal law related to explosions and arson. Historical introduction to explosives. Gunpowder: comp
The course does not provide for the adoption of a single reference text. However, material will be provided for each topic, both from textbooks and from scientific publications.
The teaching activity will see mainly the conduct of frontal lessons in the classroom. No specific laboratory activities are planned, but as far as possible and compatibly with the safety in the classrooms where the lessons will be held, we will try to show some experimental details on some applications of forensic investigation techniques.
The lecturer is available to more details and clarifications on any requests made by the students receiving at his office by previous contact via email: andrea.penoni@uninsubria.it or by phone (031-2386440).