ADVANCED TECHNIQUES IN FORENSIC SCIENCE

SHE Level 4
SCQF Credit Points 20.00
ECTS Credit Points 10.00
Module Code MHF424200
Module Leader Mahesh Uttamlal
School School of Computing, Engineering and Built Environment
Subject Chemical Science
Trimester
  • B (January start)

Pre-Requisite Knowledge

M3F124481 Instrumental Analytical Chemistry,

Summary of Content

The module will develop the students' understanding of instrumental methods of analysis that will enable the selection and justification of practical procedures in response to forensic investigations of hairs, fibres, paper, gunshot residues and materials failures. Techniques will include; conventional far-field confocal microscopy, atomic force microscopy, scanning tunnelling microscopy (STM), X-ray Diffraction (XRD) and electron microscopy with EDX.

Syllabus

CONFOCAL MICROSCOPY The microscope, operation and theory. Imaging techniques; multi-fluorescent labelling. Microscopy of cells, tissues and hair. X-RAY DIFFRACTION (XRD) The unit cell. Bravais lattices. Miller indices. Diffraction from planes, the Bragg condition, d-spacing calculations, systematic absences, diffraction patterns, indexing and identification of Miller indices. X-ray diffraction techniques - Laue, single crystal and powder. Identification of phases via JCPDS data bank. Intensities and the structure factor (Lorentz, geometric and compositional components). X-radiation sources (including synchrotron radiation). Neutron diffraction, information content. Rietveld profile analysis. SCANNING ELECTRON MICROSCOPY (SEM) Electron beam production and focusing. Interaction of electrons with matter. Detectors and image formation (topographical and compositional), depth of field advantage. Wavelength dispersion (WDX) and energy dispersion techniques (EDX). Electron microscopy in the analysis of paper, hairs, fibres, and gunshot residues. ATOMIC FORCE MICROSCOPY (AFM) Electrical interaction between atoms and molecules - force distance curves The microscopy and instrumentation Tips and resolution Imaging modes; contact, non-contact, AC and phase. Application of AFM in the analysis of hair, fibres, papers and biological samples. SCANNING TUNNELLING MICROSCOPY (STM) Electron tunnelling The microscope and instrumentation Tips and resolutions Application of STM in the analysis of electrically conducting samples SUPER RESOLUTION MICROSCOPY Short introduction to techniques in super resolution microscopy, e.g. STED, NSOM. THE PROJECT The coursework will consist of a case study in the use of the above techniques (and others, as appropriate) for the analysis of a sample important in forensic investigation, e.g. hair, fibres, papers, metals etc. Students will analyse the data and critically evaluate the merits of each technique for the analysis. The work will be reported in the form of a structured report. The syllabus consists of a list of topics normally covered within the module. Each topic may not be dealt with in the same detail.

Learning Outcomes

On successful completion of the module the student should be able to:1. Understand the principles of advanced microscopy techniques such as AFM and SEM/EDX. 2. Understand the principles of atomic force microscopy and its application to the analysis of a range of sample types including hairs and fibres.3. Understand the principles of XRD and the application of this technique to the analysis of solid samples.4. Understand the principles and application of scanning tunnelling microscopy (STM)5. Understand the causes of failure of materials in service and apply appropriate analytical techniques for their investigation6. Critically review, compare and evaluate, appropriate microscopic strategies to address a real forensic analytical problem.7. Undertake an investigative forensic project, integrating the techniques covered in the module and present a critical, sound and clear analysis of the investigation, in a formal forensic report.

Teaching / Learning Strategy

The module will be delivered through a combination of lectures, laboratory demonstrations/exercises and tutorials. Students will be supported by use of the managed learning environment GCULearn where appropriate. Students will develop a deeper understanding of the topics through reading recommended texts and reference to on-line peer-reviewed papers available from the library. This knowledge will be discussed in tutorial classes and tested by written examination. Laboratory skills in microscopy and imaging will be developed through instruction. Their ability to operate microscopes professionally will be tested in an individual project involving sample(s) associated with forensic investigation. The ability to critically evaluate microscopic images collected during the project will be evaluated through a written scientific report of publication standard. Time management and competence in using software packages developed over previous academic years are essential for the successful completion of this module.

Indicative Reading

Greaves, P. H., Microscopy of textile fibres (1995) Oxford: BIOS Scientific in association with the Royal Microscopical Society. (ISBN: 1872748244) Bonnell, Dawn A, Scanning probe microscopy and spectroscopy : theory, techniques, and applications, 2nd Ed. (2001) Wiley-VCH. (ISBN: 047124824X) Goodhew, Peter J., Electron microscopy and analysis. 2nd Ed. (1988) London: Taylor & Francis. (ISBN: 0850664144/0850664152) Cullity, B. D., Stock, S.R., Elements of x-ray diffraction. 3rdEd (2001), Prentice Hall. (ISBN: 0201610914) Eaton, Peter & West, Paul., Atomic Force Microscopy. 2010, Oxford Scholarship Online DOI: 10.1093/acprof:oso/9780199570454.001.0001 Yoshio Wasenda Eiichiro Matsubara Kozo Shinoda;, X-Ray Diffracton Crytallography: Introduction, Examples and Solved Problems., 2011, Springer Berlin Heidelberg, ISBN: 9783642166358 (e-book) Price, Robert L and W Gray (Jay) Jerome; Basic Confocal Microscopy, 2011, Springer New York; ISBN: 9780387781754 (e-book)

Transferrable Skills

On completion of the module the student should have developed the following transferable skills: Communications skills - orals skills will be developed during regular discussion of the project with supervisor. Written skills will be enhanced during the recording of data and writing of the project report. Practical skills - the student will engage in the handling of chemicals and the operations of high-end laboratory instrumentation. IT skills - will be developed in the processing and manipulation of experimental data and the preparation of the project report. Time management skills - the execution of the project will require good time management. Deadlines will have to be met in order to achieve the best possible outcomes.

Module Structure

Activity Total Hours
Practicals (FT) 36.00
Tutorials (FT) 12.00
Independent Learning (FT) 96.00
Assessment (FT) 20.00
Lectures (FT) 36.00

Assessment Methods

Component Duration Weighting Threshold Description
Coursework 1 n/a 50.00 35% 1 project report: practical project making use of the various microscopes on a forensic sample Learning outcomes 7, 8
Exam (Exams Office) 3.00 50.00 35% 3 hour unseen paper consisting of 6 questions from which students should attempt any four. Learning outcomes 1-6