Training of chemistry studentsTraining of chemistry students

in the Institute of Forensic in the Institute of Forensic ResearchResearch

Janina Zięba-PalusJanina Zięba-Palus

Lecture: „Chemistry in criminslistics” – 30 h

„Forensic Toxicology” - 30 h

Laboratory courses (each 5 h)

examination of paint

fibres identifacation

examination of glass

GSR examination

examination of ink

drugs

inorganic poisons

Seminar (1 h) - before each laboratory taining

Forensic ChemistryForensic Chemistry

Participants:Participants:• students of chemistry (4th year of study)

• group consist of 12 - 14 people

• during lab training students are divided into two groups

• performing practical exercises using analytical equipment (microscopes, spectrometers) and preparing reports basing on the obtained results

• they elaborate „mini projects”- research and literature study in the field of forensic chemistry – 4th year, II semester

• they elaborate master thesis during two semesters - 5th year:

- on identification of car paints by the use of IR, SEM/EDX,

Py-GC/MS or Vis spectrometry

- on examination of GSR by the use of SEM/EDX

- on differentiation of glass fragments using SEM/EDX , RI

- on identification of fibres using optical microscopy

- on organic and inorganic poisons identification

• summer practice is performed – two weeks

• sometimes they are employed within research project financed

by Polish government and EU

Moreover,

• students of Strathclyde University (Glasgow) prepare their master thesis – 3 months

• students from Fachschule in Instein (Germany) – practical training during 5 months

PaintsPaints

Optical microscopy:Optical microscopy:

- morphology- morphology

- layer structure- layer structure

- colourcolour

- pigmentspigments

IR spectroscopy –SEM/EDXIR spectroscopy –SEM/EDX

IR spectroscopyIR spectroscopychemical content of each layerchemical content of each layer

FibresFibres

Optical microscopy, SEMOptical microscopy, SEM - - morphologymorphology

Vis Vis spectroscopyspectroscopy

comparison of fibre comparison of fibre colourcolour

IR spectroscopyIR spectroscopy

identification of polymer

(type of fibre)

GlassGlass

Grim 2Grim 2

RI measurementRI measurement

SEM/EDXSEM/EDX – quantitative elemental – quantitative elemental analysis in order to analysis in order to classifclassify and y and

comparecompare of glass fragments of glass fragments using using chemometric methodschemometric methods

- ślady organiczne

- ślady nieorganiczne

GSRGSR

Metal particlesMetal particles

Metal particles:- spherical shape- several microns in diameter- specific composition

SEM/EDXSEM/EDX

InksInks

absorption in white light

absorption in IR light

VSCVSC

600 800 1000 1200 1400 1600 1800

red gel 03 PRAXIS red gel 03 FORAM red gel 03 Renishow

Raman Raman spectroscopyspectroscopy

Extraction solution

• Pyridine

1. Isolation of writing materials from paper

Three types of elution solutions

• Butanol : ethanol : Distilled water : acetic acid

• Ethyl acetate : ethanol : distilled water

• Ethyl acetate : propanol : distilled water : acetic acid

2. Developing of chromatograms

Observation of chromatograms in UV/VIS light

3. Interpretation of chromatograms

black ink

acid blue

blue gel

glicerine

styrene

IR spectroscopyIR spectroscopy