Bright NJ, Webb RP, Bleay S, Hinder S, Ward N, Watts JF, Kirkby KJ, Bailey MJ (2012) Determination of the deposition order of overlapping latent fingerprints and inks using Secondary Ion Mass Spectrometry (SIMS), Analytical Chemistry ACS Publications
A new protocol using time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been developed to identify the deposition order of a fingerprint overlapping an ink line on paper. By taking line scans of fragment ions characteristic of the ink molecules (m/z 358.2 and 372.2) where the fingerprint and ink
overlap and by calculating the normalised standard deviation of the intensity variation across the line scan, it is possible to determine whether or not a fingerprint is above ink on a paper substrate. The
protocol adopted works for a selection of fingerprints from four donors tested here and for a fingerprint that was aged for six months; for one donor, the very faint fingerprints could not be visualized using
either standard procedures (ninhydrin development) or SIMS and therefore the protocol correctly gives an inconclusive result.
Bailey MJ, Bright NJ, Croxton RS, Francese S, Ferguson LS, Hinder S, Jickells S, Jones BJ, Jones BN, Kazarian SG, Ojeda JJ, Webb RP, Wolstenholme R, Bleay S (2012) Chemical characterization of latent fingerprints by matrix-assisted laser desorption ionization, time-of-flight secondary ion mass spectrometry, mega electron volt secondary mass spectrometry, gas chromatography/mass spectrometry, X-ray photoelectron spectroscopy, and attenuated total reflection Fourier transform infrared spectroscopic imaging: An intercomparison, Analytical Chemistry 84 (20) pp. 8514-8523
The first analytical intercomparison of fingerprint residue using equivalent samples of latent fingerprint residue and characterized by a suite of relevant techniques is presented. This work has never been undertaken, presumably due to the perishable nature of fingerprint residue, the lack of fingerprint standards, and the intradonor variability, which impacts sample reproducibility. For the first time, time-of-flight secondary ion mass spectrometry, high-energy secondary ion mass spectrometry, and X-ray photoelectron spectroscopy are used to target endogenous compounds in fingerprints and a method is presented for establishing their relative abundance in fingerprint residue. Comparison of the newer techniques with the more established gas chromatography/mass spectrometry and attenuated total reflection Fourier transform infrared spectroscopic imaging shows good agreement between the methods, with each method detecting repeatable differences between the donors, with the exception of matrix-assisted laser desorption ionization, for which quantitative analysis has not yet been established. We further comment on the sensitivity, selectivity, and practicability of each of the methods for use in future police casework or academic research. © 2012 American Chemical Society.
Bailey M (2014) Untitled, X-RAY SPECTROMETRY 43 (1) pp. 1-1
Ugarte M, Grime GW, Lord GM, Geraki K, Collingwood JF, Finnegan ME, Farnfield H, Merchant M, Bailey MJ, Ward NI, Foster PJ, Bishop PN, Osborne NN (2012) Concentration of various trace elements in the rat retina and their distribution in different structures, Metallomics: integrated biometal science
Bailey Melanie, Ismail Mahado, Bleay S, Bright N, Elad ML, Cohen Y, Geller B, Everson D, Costa Catia, Webb RP, Watts JF, de Puit M (2013) Enhanced imaging of developed fingerprints using mass spectrometry imaging, ANALYST 138 (21) pp. 6246-6250
ROYAL SOC CHEMISTRY
Latent fingermarks are invisible to the naked eye and normally require the application of a chemical developer followed by an optical imaging step in order to visualize the ridge detail. If the finger deposition is poor, or the fingermark is aged, it can sometimes be difficult to produce an image of sufficient quality for identification. In this work, we show for the first time how mass spectrometry imaging (in this case time-of-flight secondary ion mass spectrometry, ToF-SIMS) can be used to enhance the quality of partially recovered fingermarks. We show three examples of how chemical imaging can be used to obtain enhanced images of fingermarks deposited on aluminium foil, glass and the handle of a hand grenade compared with conventional development techniques. © 2013 The Royal Society of Chemistry.
Campana MG, Bower MA, Bailey MJ, Stock F, O'Connell TC, Edwards CJ, Checkley-Scott C, Knight B, Spencer M, Howe CJ (2010) A flock of sheep, goats and cattle: ancient DNA analysis reveals complexities of historical parchment manufacture, JOURNAL OF ARCHAEOLOGICAL SCIENCE 37 (6) pp. 1317-1325 ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
Webb M, Jeynes C, Gwilliam R, Too P, Kozanecki A, Domagala J, Royle A, Sealy B (2005) The influence of the ion implantation temperature and the dose rate on smart-cut (c) in GaAs, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 240 (1-2) pp. 142-145 ELSEVIER SCIENCE BV
Kaabar W, Daar E, Gundogdu O, Jenneson PM, Farquharson MJ, Webb M, Jeynes C, Bradley DA (2009) Metal deposition at the bone-cartilage interface in articular cartilage, APPLIED RADIATION AND ISOTOPES 67 (3) pp. 475-479 PERGAMON-ELSEVIER SCIENCE LTD
There are many technical challenges in the fabrication of devices from novel materials. The characterization of these materials is critical in the development of efficient photovoltaic systems. We show how the application of recent advances in MeV IBA, providing the self-consistent treatment of RBS (Rutherford backscattering) and PIXE (particle induced X-ray emission) spectra, makes a new set of powerful complementary depth profiling techniques available for all thin film technologies, including the chalcopyrite compound semiconductors. We will give and discuss a detailed analysis of a CuInAl metallic precursor film, showing how similar methods are also applicable to other films of interest.
Bright NJ, Webb RP, Kirkby KJ, Willson TR, Driscoll DJ, Reddy SM, Ward NI, Bailey MJ, Bleay S (2013) Chemical changes exhibited by latent fingerprints after exposure to vacuum conditions, Forensic Science International
The effect of vacuum exposure on latent fingerprint chemistry has been evaluated. Fingerprints were analysed using a quartz crystal microbalance to measure changes in mass, gas chromatography mass spectrometry to measure changes in lipid composition and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to determine changes in the content of water, fatty acids and their esters after exposure to vacuum. The results are compared with samples aged under ambient conditions. It was found that fingerprints lose around 26% of their mass when exposed to vacuum conditions, equivalent to around 5 weeks ageing under ambient conditions. Further exposure to vacuum causes a significant reduction in the lipid composition of a fingerprint, in particular with the loss of tetradecanoic and pentadecanoic acid, that was not observed in ambient aged samples. There are therefore implications for sequence in which fingerprint development procedures (for example vacuum metal deposition) are carried out, as well as the use of vacuum based methods such as secondary ion mass spectrometry (SIMS) and matrix-assisted laser desorption ionisation (MALDI) in the study of fingerprint chemistry. © 2013.
Kaabar W, Daar E, Bunk O, Farquharson MJ, Laklouk A, Bailey M, Jeynes C, Gundogdu O, Bradley DA (2010) Elemental and structural studies at the bone-cartilage interface, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 652 (1) pp. 786-790
Christopher ME, Warmenhoeven JW, Romolo FS, Donghi M, Webb RP, Jeynes C, Ward NI, Kirkby KJ, Bailey MJ (2013) A new quantitative method for gunshot residue analysis by ion beam analysis., Analyst pp. 4649-4655 Royal Society of Chemistry
Imaging and analyzing gunshot residue (GSR) particles using the scanning electron microscope equipped with an energy dispersive X-ray spectrometer (SEM-EDS) is a standard technique that can provide important forensic evidence, but the discrimination power of this technique is limited due to low sensitivity to trace elements and difficulties in obtaining quantitative results from small particles. A new, faster method using a scanning proton microbeam and Particle Induced X-ray Emission (¼-PIXE), together with Elastic Backscattering Spectrometry (EBS) is presented for the non-destructive, quantitative analysis of the elemental composition of single GSR particles. In this study, the GSR particles were all Pb, Ba, Sb. The precision of the method is assessed. The grouping behaviour of different makes of ammunition is determined using multivariate analysis. The protocol correctly groups the cartridges studied here, with a confidence >99%, irrespective of the firearm or population of particles selected.
Bailey Melanie, Randall EC, Costa Catia, Salter T, Race AM, de Puit M, Koeberg M, Baumert M, Bunch J (2016) Analysis of Urine, Oral fluid and Fingerprints by Liquid Extraction Surface Analysis Coupled to High Resolution MS and MS/MS ? Opportunities for Forensic and Biomedical Science, Analytical Methods 8 (16) pp. 3373-3382
Royal Society of Chemistry
Liquid Extraction Surface Analysis (LESA) is a new, high throughput tool for ambient mass spectrometry. A solvent droplet is deposited from a pipette tip onto a surface and maintains contact with both the surface and the pipette tip for a few seconds before being re-aspirated. The technique is particularly suited to the analysis of trace materials on surfaces due to its high sensitivity and low volume of sample removal. In this work, we assess the suitability of LESA for obtaining detailed chemical profiles of fingerprints, oral fluid and urine, which may be used in future for rapid medical diagnostics or metabolomics studies. We further show how LESA can be used to detect illicit drugs and their metabolites in urine, oral fluid and fingerprints. This makes LESA a potentially useful tool in the growing field of fingerprint chemical analysis, which is relevant not only to forensics but also to medical diagnostics. Finally, we show how LESA can be used to detect the explosive material RDX in contaminated artificial fingermarks.
Bright NJ, Willson TR, Driscoll DJ, Reddy SM, Webb RP, Bleay S, Ward NI, Kirkby KJ, Bailey MJ (2013) Chemical changes exhibited by latent fingerprints after exposure to vacuum conditions, Forensic Science International 230 (1-3) pp. 81-86
The effect of vacuum exposure on latent fingerprint chemistry has been evaluated. Fingerprints were analysed using a quartz crystal microbalance to measure changes in mass, gas chromatography mass spectrometry to measure changes in lipid composition and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to determine changes in the content of water, fatty acids and their esters after exposure to vacuum. The results are compared with samples aged under ambient conditions. It was found that fingerprints lose around 26% of their mass when exposed to vacuum conditions, equivalent to around 5 weeks ageing under ambient conditions. Further exposure to vacuum causes a significant reduction in the lipid composition of a fingerprint, in particular with the loss of tetradecanoic and pentadecanoic acid, that was not observed in ambient aged samples. There are therefore implications for sequence in which fingerprint development procedures (for example vacuum metal deposition) are carried out, as well as the use of vacuum based methods such as secondary ion mass spectrometry (SIMS) and matrix-assisted laser desorption ionisation (MALDI) in the study of fingerprint chemistry. © 2013 .
Bailey MJ, Kirkby KJ, Jeynes C (2009) Trace element profiling of gunshot residues by PIXE and SEM-EDS: a feasibility study, X-RAY SPECTROMETRY 38 (3) pp. 190-194 JOHN WILEY & SONS LTD
Bailey Melanie, Bradshaw R, Francese S, Salter T, De Puit M, Costa Catia, Ismail M, Bosman I, Wolff K, Webb Roger (2015) Rapid Detection of Cocaine, Benzoylecgonine and Methylecgonine in Fingerprints using Surface Mass Spectrometry, The Analyst 140 (18) pp. 6254-6259
Latent fingerprints provide a potential route to the secure, high throughput and non-invasive detection of drugs of abuse. In this study we show for the first time that the excreted metabolites of drugs of abuse can be detected in fingerprints using ambient mass spectrometry. Fingerprints and oral fluid were taken from patients attending a drug and alcohol treatment service. Gas chromatography mass spectrometry (GC-MS) was used to test the oral fluid of patients for the presence of cocaine and benzoylecgonine. The corresponding fingerprints were analysed using Desorption Electrospray Ionization (DESI) which operates under ambient conditions and Ion Mobility Tandem Mass Spectrometry Matrix Assisted Laser Desorption Ionization (MALDI-IMS-MS/MS) and Secondary Ion Mass Spectrometry (SIMS). The detection of cocaine, benzoylecgonine (BZE) and methylecgonine (EME) in latent fingerprints using both DESI and MALDI showed good correlation with oral fluid testing. The sensitivity of SIMS was found to be insufficient for this application. These results provide exciting opportunities for the use of fingerprints as a new sampling medium for secure, non-invasive drug detection. The mass spectrometry techniques used here offer a high level of selectivity and consume only a small area of a single fingerprint, allowing repeat and high throughput analyses of a single sample.
Webb M, Jeynes C, Gwilliam R, Royle A, Sealy B (2006) Characterising ion-cut in GaAs by Rutherford backscattering spectroscopy, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 249 (1-2) pp. 429-431 Elsevier
Bailey MJ, Jones BN, Hinder S, Watts J, Bleay S, Webb RP (2010) Depth profiling of fingerprint and ink signals by SIMS and MeV SIMS, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 268 (11-12) pp. 1929-1932 ELSEVIER SCIENCE BV
Bailey MJ (2010) Depth Profiling of Fingerprint and Ink Signals by SIMS and MeV SIMS, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 268 (11-12) pp. 1929-1932
Police institutions currently have no analytical method of knowing whether a fingerprint was deposited before or after the document was written or printed. The suitability of using MeV secondary ion mass spectrometry (i.e. SIMS with an MeV ion beam) to determine the order in which a fingerprint and written text were deposited on paper was therefore investigated. A 10 MeV O4+ beam was used to generate secondary ions from the surface of the samples and to map the molecular fragments from doped fingerprints and inks on paper. The images obtained and the sputtering behaviour of the samples was found to be indicative of the sequence of ink and fingerprint deposits.
Jeynes JCG, Webb M, Kirkby KJ, Kirkby NF, Bradley DA (2009) Proceedings of the First International Conference on Biomedical Applications of High Energy Ion Beams Preface, APPLIED RADIATION AND ISOTOPES 67 (3) pp. 369-370 PERGAMON-ELSEVIER SCIENCE LTD
Bailey MJ, Morgan RM, Comini P, Calusi S, Bull PA (2012) Evaluation of particle-induced X-ray emission and particle-induced ³-ray emission of quartz grains for forensic trace sediment analysis., Anal Chem 84 (5) pp. 2260-2267
The independent verification in a forensics context of quartz grain morphological typing by scanning electron microscopy was demonstrated using particle-induced X-ray emission (PIXE) and particle-induced ³-ray emission (PIGE). Surface texture analysis by electron microscopy and high-sensitivity trace element mapping by PIXE and PIGE are independent analytical techniques for identifying the provenance of quartz in sediment samples in forensic investigations. Trace element profiling of the quartz grain matrix separately from the quartz grain inclusions served to differentiate grains of different provenance and indeed went some way toward discriminating between different quartz grain types identified in a single sample of one known forensic provenance. These results confirm the feasibility of independently verifying the provenance of critical samples from forensic cases.
Howard KT, Bailey MJ, Berhanu D, Bland PA, Cressey G, Howard LE, Jeynes C, Matthewman R, Martins Z, Sephton MA, Stolojan V, Verchovsky S (2013) Biomass preservation in impact melt ejecta, Nature Geoscience 6 (12) pp. 1018-1022
Meteorites can have played a role in the delivery of the building blocks of life to Earth only if organic compounds are able to survive the high pressures and temperatures of an impact event. Although experimental impact studies have reported the survival of organic compounds, there are uncertainties in scaling experimental conditions to those of a meteorite impact on Earth and organic matter has not been found in highly shocked impact materials in a natural setting. Impact glass linked to the 1.2-km-diameter Darwin crater in western Tasmania is strewn over an area exceeding 400 km 2 and is thought to have been ejected by a meteorite impact about 800 kyr ago into terrain consisting of rainforest and swamp. Here we use pyrolysis-gas chromatography-mass spectrometry to show that biomarkers representative of plant species in the local ecosystem - including cellulose, lignin, aliphatic biopolymer and protein remnants - survived the Darwin impact. We find that inside the impact glass the organic components are trapped in porous carbon spheres. We propose that the organic material was captured within impact melt and preserved when the melt quenched to glass, preventing organic decomposition since the impact. We suggest that organic material can survive capture and transport in products of extreme impact processing, at least for a Darwin-sized impact event. © 2013 Macmillan Publishers Limited.
Ugarte M, Grime GW, Lord G, Geraki K, Collingwood JF, Finnegan ME, Farnfield H, Merchant M, Bailey MJ, Ward NI, Foster PJ, Bishop PN, Osborne NN (2012) Concentration of various trace elements in the rat retina and their distribution in different structures, Metallomics 4 (12) pp. 1245-1254
Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the total amount of trace elements in retina from adult male Sprague-Dawley rats (n = 6). Concentration of trace elements within individual retinal areas in frozen sections of the fellow eye was established with the use of two methodologies: (1) particle-induced X-ray emission (PIXE) in combination with 3D depth profiling with Rutherford backscattering spectrometry (RBS) and (2) synchrotron X-ray fluorescence (SXRF) microscopy. The most abundant metal in the retina was zinc, followed by iron and copper. Nickel, manganese, chromium, cobalt, selenium and cadmium were present in very small amounts. The PIXE and SXRF analysis yielded a non-homogenous pattern distribution of metals in the retina. Relatively high levels of zinc were found in the inner part of the photoreceptor inner segments (RIS)/outer limiting membrane (OLM), inner nuclear layer and plexiform layers. Iron was found to accumulate in the retinal pigment epithelium/choroid layer and RIS/OLM. Copper in turn, was localised primarily in the RIS/OLM and plexiform layers. The trace elements iron, copper, and zinc exist in different amounts and locations in the rat retina. © 2012 The Royal Society of Chemistry.
Jeynes JCG, Bailey MJ, Coley H, Kirkby KJ, Jeynes C (2010) Microbeam PIXE analysis of platinum resistant and sensitive ovarian cancer cells, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 268 (11-12) pp. 2168-2171 ELSEVIER SCIENCE BV
Jeynes C, Bailey MJ, Bright NJ, Christopher ME, Grime GW, Jones BN, Palitsin VV, Webb RP (2012) "total IBA" - Where are we?, Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms 271 pp. 107-118
The suite of techniques which are available with the small accelerators used for MeV ion beam analysis (IBA) range from broad beams, microbeams or external beams using the various particle and photon spectrometries (including RBS, EBS, ERD, STIM, PIXE, PIGE, NRA and their variants), to tomography and secondary particle spectrometries like MeV-SIMS. These can potentially yield almost everything there is to know about the 3-D elemental composition of types of samples that have always been hard to analyse, given the sensitivity and the spacial resolution of the techniques used. Molecular and chemical information is available in principle with, respectively, MeV-SIMS and high resolution PIXE. However, these techniques separately give only partial information ? the secret of ?Total IBA? is to find synergies between techniques used simultaneously which efficiently give extra information. We here review how far ?Total IBA? can be considered already a reality, and what further needs to be done to realise its full potential.
Bailey MJ, Howard KT, Kirkby KJ, Jeynes C (2009) Characterisation of inhomogeneous inclusions in Darwin glass using ion beam analysis, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 267 (12-13) pp. 2219-2224 ELSEVIER SCIENCE BV
Perusko D, Webb MJ, Milinovic V, Timotijevic B, Miosavljevic M, Jeynes C, Webb RP (2008) On the ion irradiation stability of Al/Ti versus AlN/TiN multilayers, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 266 (8) pp. 1749-1753 ELSEVIER SCIENCE BV
Webb R, Bailey M, Jeynes C, Grime G (2010) 19th International Conference on Ion Beam Analysis, Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms 268 (11-12)
Attard-Montalto N, Ojeda JJ, Reynolds A, Ismail M, Bailey M, Doodkorte L, De Puit M, Jones BJ (2014) Determining the chronology of deposition of natural fingermarks and inks on paper using secondary ion mass spectrometry, Analyst 139 (18) pp. 4641-4653
This study thoroughly explores the use of time-of-flight secondary ion mass spectrometry (ToF-SIMS) for determining the deposition sequence of fingermarks and ink on a porous paper surface. Our experimental work has demonstrated that mapping selected endogenous components present in natural fingermarks enables the observation of friction ridges on a laser-printed surface, only when a fingerprint is deposited over this layer of ink. Further investigations have shown limited success on ink-jet printing and ballpoint pen inks. 51 blind tests carried out on natural, latent fingermarks on laser-printed surfaces; up to 14th depletion with samples aged for up to 421 days have resulted in a 100% success rate. Development with ninhydrin was found to affect the fingermark residue through mobilisation of ions, therefore sequencing determination was compromised; whilst iodine fuming and 1,2-indanedione developers did not. This implied that selected development methods affected success in fingermark-ink deposition order determination. These results were further corroborated through inter-laboratory validation studies. The adopted protocol and extensive series of tests have therefore demonstrated the effectiveness and limitations of ToF-SIMS in providing chronological sequencing information of fingermarks on questioned documents; successfully resolving this order of deposition query. This journal is © the Partner Organisations 2014.
Bailey MJ, Jeynes C, Sealy BJ, Webb RP, Gwilliam RM (2010) On artefacts in the secondary ion mass spectrometry profiling of high fluence H+ implants in GaAs, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 268 (11-12) pp. 2051-2055 ELSEVIER SCIENCE BV
Bailey M (2010) Surface analysis techniques in forensic science, Surface and Interface Analysis 42 (5) pp. 339-340
Hashim S, Al-Ahbabi S, Bradley DA, Webb M, Jeynes C, Ramli AT, Wagiran H (2009) The thermoluminescence response of doped SiO2 optical fibres subjected to photon and electron irradiations, APPLIED RADIATION AND ISOTOPES 67 (3) pp. 423-427 PERGAMON-ELSEVIER SCIENCE LTD
Webb M, Jeynes C, Gwilliam RM, Tabatabaian Z, Royle A, Sealy BJ (2005) The influence of the ion implantation temperature and the flux on smart-cut (c) in GaAs, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 237 (1-2) pp. 193-196 ELSEVIER SCIENCE BV
Romolo FS, Christopher ME, Jeynes C, Webb RP, Kirkby KJ, Donghi M, Ripani L, Ward NI, Bailey MJ (2013) Integrated Ion Beam Analysis (IBA) in Gunshot Residue (GSR) characterisation, Forensic Science International 231 (1-3) pp. 219-228
Gunshot Residue (GSR) is residual material from the discharge of a firearm, which frequently provides crucial information in criminal investigations. Changes in ammunition manufacturing are gradually phasing out the heavy metals on which current forensic GSR analysis is based, and the latest Heavy Metal Free (HMF) primers urgently demand new forensic solutions. Proton scanning microbeam Ion Beam Analysis (IBA), in conjunction with the Scanning Electron Microscope equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDS), can be introduced into forensic analysis to solve both new and old problems, with a procedure entirely commensurate with current forensic practice. Six cartridges producing GSR particles known to be interesting in casework by both experience and the literature were selected for this study. A standard procedure to relocate the same particles previously analysed by SEM-EDS, based on both secondary electron (SE) and X-ray imaging was developed and tested. Elemental Particle Induced X-ray Emission (PIXE) mapping of the emitted X-rays allowed relocation in a scan of 10¼m×10¼m of even a 1¼m GSR particle. The comparison between spectra from the same particle obtained by SEM-EDS and IBA-PIXE showed that the latter is much more sensitive at mid-high energies. Results that are very interesting in a forensic context were obtained with particles from a cartridge containing mercury fulminate in the primer. Particle-induced gamma-ray emission (PIGE) maps of a particles from HMF cartridges allowed identification of Boron and Sodium in particles from hands using the B(p,±³)Be, B(p,p³)B and Na(p,p³)Na reactions, which is extraordinary in a forensic context. The capability for quantitative analysis of elements within individual particles by IBA was also demonstrated, giving the opportunity to begin a new chapter in the research on GSR particles. The integrated procedure that was developed, which makes use of all the IBA signals, has unprecedented characterisation and discrimination power for GSR samples. © 2013 Elsevier Ireland Ltd.
Shcherbachev K, Bailey MJ (2011) Influence of implantation conditions of He+ ions on the structure of a damaged layer in GaAs(001), Physica Status Solidi (A) Applications and Materials 208 (11) pp. 2576-2581 Wiley
Bradley DA, Farquharson MJ, Gundogdu O, Al-Ebraheem A, Ismail EC, Kaabar W, Bunk O, Pfeiffer F, Falkenberge G, Bailey M (2010) Applications of condensed matter understanding to medical tissues and disease progression: Elemental analysis and structural integrity of tissue scaffolds, RADIATION PHYSICS AND CHEMISTRY 79 (2) pp. 162-175 PERGAMON-ELSEVIER SCIENCE LTD
Peng N, Jeynes C, Bailey MJ, Adikaari D, Stolojan V, Webb RP (2009) High concentration Mn ion implantation in Si, NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 267 (8-9) pp. 1623-1625 ELSEVIER SCIENCE BV
Surface mass spectrometry methods can be difficult to use effectively with low cost, portable mass spectrometers. This is because commercially available portable (single quadrupole) mass spectrometers lack the mass resolution to confidently differentiate between analyte and background signals. Additionally, current surface analysis methods provide no facility for chromatographic separation and therefore are vulnerable to ion suppression. Here we present a new analytical method where analytes are extracted from a sample using a solvent flushed across the surface under high pressure, separated using a chromatography column and then analysed using a portable mass spectrometer. The use of chromatography reduces ion suppression effects and this, used in combination with in-source fragmentation, increases selectivity, thereby allowing high sensitivity to be achieved with a portable and affordable quadrupole mass spectrometer. We demonstrate the efficacy of the method for the quantitative detection of cocaine and benzoylecgonine in urine and oral fluid. The method gives relative standard deviations below 15% (with one exception), and R2 values above 0.998. The limits of detection for these analytes in oral fluid and urine are
The CdS window layer in thin film solar cells is frequently grown by chemical bath deposition (CBD). Deposited films are typically less than 100 nm thick and the inability to identify the exact start of the deposition can make CBD an imprecise process. This paper describes the construction and testing of a simple optical fibre sensor that detects the start of the deposition process and also allows for its mechanism to be studied. The in situ optical fibre monitoring technique utilises the change in optical reflectance off the glass/deposited film/precursor solution interfaces at an operating wavelength of 1550 nm. A theoretical expression for the reflection of light from the interface is discussed and compared with experimental results. The monitoring technique shows the presence of two different deposition mechanisms. This result is confirmed by film densities calculated by Rutherford backscattering spectrometry and an optical model for ellipsometry measurements which indicates that the deposited CdS films consist of a double layer structure with a porous layer on top of a dense under layer. The application of the theoretical expression is optimised by assuming the refractive index of the CdS layer to be 2.02. The ellipsometry model shows that the refractive index of the CdS deposited is 2.14 for a two layer model of the film that included a porous upper layer through the effective medium approximation.
BACKGROUND: Paper spray mass spectrometry6 is a technique
that has recently emerged and has shown excellent
analytical sensitivity to a number of drugs in blood. As an
alternative to blood, fingerprints have been shown to
provide a noninvasive and traceable sampling matrix.
Our goal was to validate the use of fingerprint samples to
detect cocaine use.
METHODS: Samples were collected on triangular pieces
(168 mm2) of washed Whatman Grade I chromatography
paper. Following application of internal standard,
spray solvent and a voltage were applied to the paper
before mass spectrometry detection. A fingerprint visualization
step was incorporated into the analysis procedure
by addition of silver nitrate solution and exposing the
sample to ultraviolet light.
RESULTS: Limits of detection for cocaine, benzoylecgonine,
and methylecgonine were 1, 2, and 31 ng/mL respectively,
with relative standard deviations of less than 33%. No
matrix effects were observed. Analysis of 239 fingerprint
samples yielded a 99% true-positive rate and a 2.5%
false-positive rate, based on the detection of cocaine,
benzoylecgonine, or methylecgonine with use of a single
CONCLUSIONS: The method offers a qualitative and noninvasive
screening test for cocaine use. The analysis
method developed is rapid (4 min/sample) and requires
no sample preparation.
A fingerprint offers a convenient matrix for drug testing as samples can be deposited rapidly and securely. In this thesis, different strategies for quantitative analysis of fingerprint residues were explored. The variability in mass of a deposited fingerprint measured by a quartz crystal microbalance (QCM) was found to be up to 100% for multiple donors. Fingerprint depositions could be controlled to 21% for a single donor by washing hands, controlling the deposition pressure and wait time. With the aim of reducing the variability of analyte signals detected, the following approaches were tested for feasibility:
(a) Normalising the intensity of endogenous compounds to the measured mass
(b) Normalising the intensity of caffeine and its metabolites to endogenous compounds detected in multiple fingerprints using liquid chromatography-mass spectrometry (LC-MS) and in single fingerprints using liquid extraction surface analysis-mass spectrometry (LESA-MS)
(c) Developing fingerprints deposited on paper using ninhydrin and normalising to the signal intensity of Ruhemann?s purple, and to a ?photo scaling? method developed in this thesis.
(d) Normalisation to a ?fingerprint reader? developed by Intelligent Fingerprinting Limited, which gives a signal relating to the amount of fingerprint deposited on a glass slide.
Using approach (a) there was no clear relationship between the mass of fingerprint measured and the intensity of endogenous compounds measured by LC-MS. Using approach (b) it was possible to reduce (or at least maintain) the variability in replicate fingerprint depositions to below 20% as required of a quantitative method. Using approach (c) normalisation to the mean grey value and integrated density value improved variation in theobromine to below 20% in all samples. Finally using approach (d) normalisation to the ?fingerprint reader? reduced the variability below 20%. The thesis therefore concludes that either approach (b), (c), or (d) could be explored further in future work for quantification of fingerprint residues.
Recent publications have explored the
possibility of using fingerprints to confirm drug use, but
none has yet dealt with environmental contamination
from fingertips. Here we explored the possibility of establishing
an environmental cutoff for drug testing from
a single fingerprint.
Fingerprint samples (n=100) were collected
from the hands of 50 nondrug users before and after
handwashing to establish separate environmental cutoff
values and testing protocols for cocaine, benzoylecgonine,
heroin, and 6-monoacetylmorphine. The cutoff was challenged
by testing the fingerprints of drug-free volunteers
after shaking hands with drug users. Fingerprints from patients
who testified to taking cocaine (n = 32) and heroin
(n = 24) were also collected and analyzed.
A different cutoff value needed to be applied,
depending on whether the fingerprints were collected as
presented or after handwashing. Applying these cutoffs gave
a 0%false-positive rate from the drug-free volunteers. After
application of the cutoff, the detection rate (compared to
patient testimony) for washed hands of patients was 87.5%
for cocaine use and 100% for heroin use.
Fingerprints show enhanced levels of cocaine,
heroin, and their respective metabolites in patients
who testified to taking the substances, compared with the
population of na1¨ve drug users surveyed, and a cutoff
(decision level) can be established. The cutoff is robust
enough to account for small increases in analyte observed
after secondary transfer.
Direct analyte-probed nano-extraction (DAPNe) is a method of extracting material from a microscale region of a sample and provides the opportunity for detailed mass spectrometry analysis of extracted analytes from a small area. The technique has been shown to provide enhanced sensitivity compared with bulk analysis by selectively removing analytes from their matrix and has been applied for selective analysis of single cells and even single organelles. However, the quantitative capabilities of the technique are yet to be fully evaluated. In this study, various normalisation techniques were investigated in order to improve the quantitative capabilities of the technique. Two methods of internal standard incorporation were applied to test substrates, which were designed to replicate biological sample matrices. Additionally, normalisation to the extraction spot area and matrix compounds were investigated for suitability in situations when an internal standard is not available. The variability observed can be significantly reduced by using a sprayed internal standard, and in some cases, by normalising to the extracted area.
This thesis investigates the possibility of using ambient ionisation and surface mass spectrometry for the detection and quantification of drugs of abuse in latent fingerprints. The use of fingerprints for drug testing in lieu of blood, oral fluid or urine reduces the biological hazard associated with these types of samples. The sample collection procedure is non-invasive, can be monitored to prevent cheating (submitting samples from a drug free individual) and the identity of the donor is embedded in the fingerprint ridge detail. In this thesis, three techniques ? desorption electrospray ionisation (DESI), liquid extraction surface analysis (LESA) and paper spray mass spectrometry, were evaluated for their ability to provide a rapid drug test from a fingerprint.
Paper spray-mass spectrometry was chosen for further development due to the ease of set-up, rapid nature of the analysis and potential to provide quantitative results. The final optimised method included full scan mass spectrometry measurements (quantitative) followed by tandem mass spectrometry (MS/MS) scans (qualitative) for the detection of cocaine, benzoylecgonine (BZE) and ecgonine methyl ester (EME). Limits of detection (LOD) were calculated to be 1 ng/mL, 2 ng/mL and 31 ng/mL for cocaine, BZE and EME, respectively.
Using the optimised method of analysis, 159 individual fingerprint samples (collected from individuals seeking treatment for substance abuse) were analysed with a 99% true positive rate through the detection of either cocaine, BZE or EME. The detection of these substances was corroborated by a positive oral fluid result from samples collected from the same individuals. Analysis of fingerprint samples collected from the non-drug users (n=80) indicated
The significance of detecting the parent drug or metabolite in fingerprint samples was determined through the analysis of samples after contact with seized cocaine from Forensic Science Ireland. Cocaine, BZE and EME were found in fingerprints produced by contact, showing that the presence of a cocaine metabolite in a fingerprint is not enough to show that a suspect has taken a drug. Furthermore, secondary transfer scenarios showed that cocaine could be transferred through handshakes. None of the hand cleaning methods employed in this research were sufficient to remove all traces of cocaine from contact residues.
Finally, the possibility of visualising the fingerprint ridge detail prior to analysis was tested and the presence of the analytes was qualitatively confirmed in fingerprint samples after application of silver nitrate. This is an important step that allows for sample traceability, whilst still providing high throughput analysis and sensitivity.
The use of chemical analysis of fingerprints as an alternative approach for drug testing has become subject of recent publications. However, the significance of the detection of drugs in fingerprints compared to a background population of non-drug users has not yet been explored. In this research, the main area of research was to determine the forensic potential of detecting cocaine and heroin use through the analysis of fingerprints. Fingerprint samples deposited on paper were extracted using an extraction solution (10% dichloromethane in methanol) and analysed using liquid chromatography ? mass spectrometry (LC-MS). This research showed that cocaine and benzoylecgonine were detected in 100 and 94% of natural fingerprint samples (n= 65) collected from drug users, and similarly, heroin and 6-acetylmorphine were detected in 98 and 100% of samples (n = 60). Cocaine and benzoylecgonine were also detected in 13 and 5% of natural fingerprints (n = 98) from a background population of non-drug users. In contrast, heroin and 6-acetylmorphine were detected in 0 and 1% of fingerprints from the background population. For cocaine, a threshold level was required to differentiate fingerprints from drug users and environmental exposure in non-drug users (at a ratio analyte (A) to internal standard (IS) 0.015). The analytes of interest could still be detected in fingerprint samples from drug users after a hand cleaning procedure, however this resulted in a lower detection rate compared to natural fingerprints. In contrast, the analytes were not present in fingerprints collected from non-drug users after handwashing (1% false positive rate for cocaine). Furthermore, cocaine, benzoylecgonine, heroin and 6-acetylmorphine can also be detected in fingerprint samples from dermal contact with the parent drug even after the use of hand cleaning procedures. The detection of illicit drugs in fingerprints is therefore not solely indicative of administration of a drug but does indicate that these analytes are not prevalent in a background population of non-drug users. Additionally, the detection of isoniazid and acetylisoniazid in fingerprint samples from tuberculosis medication showed the potential application of fingerprint testing to monitor adherence to drug treatments. The detection window of isoniazid and acetylisoniazid (
Gunshot Residue (GSR) produced by the discharge of a firearm often provides very useful information in criminal investigations in cases involving the use of firearms. Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDS) is typically used worldwide to visualize micrometric particles constituting GSR and to analyse their elemental composition. The 2017 ASTM Standard guide for gunshot residue analysis by scanning electron microscopy/energy dispersive X-ray spectroscopy specifies that ?Particles classified as characteristic of GSR will have one of the following elemental compositions: Lead, antimony, barium; Lead, barium, calcium, silicon, tin?. For the first time, the presence of an additional element, such as Sn, plays a key role in ASTM particle classification. It is known that some ammunitions, used for pistols, revolvers and rifles, contain tin foil discs for sealing the primer mixture into the cup, resulting in GSR particles containing Sn. The authors faced some cases in which Sn was unexpectedly found in GSR particles from a 0.22 Long Rifle derringer and from some 12 gauge shotguns. No tin foil discs are used in rimfire ammunitions and there is no published evidence of tin foil discs in shotshell ammunitions. Following a ?case by case? approach, experimental research has been carried out to explain how Sn can be present in GSR particles when the last discharged cartridge also does not contain any Sn either in components and in the explosive charges.
Moreover, the use of Particle Induced X-ray Emission (PIXE) showed the capability to overcome overlap ambiguity of Sb and Sn peaks in the X-ray spectra, being a possible key issue in real shooting cases if Sn quantities are below the lower limit of SEM detection, especially when Sb is also present.
The use of synthetic stimulants, including designer cathinones, remains a significant concern worldwide.
Thus, the detection and identification of synthetic cathinones in biological matrices is of paramount
importance for clinical and forensic laboratories. In this study, distribution of mephedrone and its metabolites was investigated in fingerprints. Following a controlled human mephedrone administration (100 mg
nasally insufflated), two mass spectrometry-based methods for fingerprint analysis have been evaluated.
The samples deposited on triangular pieces of chromatography paper were directly analysed under
ambient conditions by paper spray-mass spectrometry (PS-MS) while those deposited on glass cover slips
were extracted and analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The
LC-MS/MS method was 5?6 times more sensitive than PS-MS but required sample preparation and
longer analysis time. Mephedrone was detected in 62% and in 38% of all post-administration samples analysed
by LC-MS/MS and PS-MS, respectively. Nor-mephedrone was the only metabolite detected in 3.8%
of all samples analysed by LC-MS/MS. A large inter- and intra-subject variation was observed for mephedrone
which may be due to several factors, such as the applied finger pressure, angle and duration of
contact with the deposition surface and inability to control the ?amount? of collected fingerprint deposits.
Until these limitations are addressed, we suggest that the sole use of fingerprints can be a useful diagnostic
tool in qualitative rather than quantitative analysis, and requires a confirmatory analysis in a different
The constantly growing field of the true one cell analysis provides important information on the direct chemical composition of various cells and cellular compartments. Since the heterogeneity of individual cells has been established, more researchers are interested in the chemical differences between individual cells and that is the only analysis of the one cell can determine. This results in new technologies and methods being reported regularly. This review highlights the common techniques of micro- and nanomanipulation, Raman spectroscopy, microsocopy, and mass spectrometric imaging as they pertain to the true one cell chemical analysis.
Costa Catia, van Es Elsje M., Sears Patrick, Bunch Josephine, Palitsin Vladimir, Mosegaard Kirst, Bailey Melanie (2019) Exploring Rapid, Sensitive and Reliable Detection of Trace Explosives Using Paper Spray Mass Spectrometry (PS?MS), Propellants, Explosives, Pyrotechnics 44 (8) pp. 1021-1027
Wiley-VCH Verlag GmbH & Co
In this publication we work towards providing fast, sensitive and selective analysis of explosive compounds collected on swabs using paper spray mass spectrometry. We have (a) increased the size of the paper spray substrate to 1.6×2.1 cm for compatibility with current practise
in swabbing for explosive material; (b) developed a method for determining a successful extraction of analyte from the substrate to reduce false negative events; and (c) expanded the range of analytes that can be detected using paper spray to include the peroxide explosive HMTD, as well as nitroglycerine (NG), picric acid (PA) and tetryl. We report the development of a 30 s method for the simultaneous
detection of 7 different explosive materials using PSMS with detection limits below 25 pg, as well as detection of HMTD at 2500 pg, showing an improvement on previously published work.
RATIONALE: Paper spray offers a rapid screening test without the need for sample preparation. The incomplete extraction of paper spray allows for further testing using more robust, selective and sensitive techniques such as liquid chromatography mass spectrometry (LC-MS). Here we develop a two-step process of paper spray followed by LC-MS to (1) rapidly screen a large number of samples and (2) confirm any disputed results. This demonstrates the applicability for testing medication adherence from a fingerprint.
METHODS: Following paper spray analysis, drugs of abuse samples were analysed using LC-MS. All analyses were completed using a Q Exactive" Plus Orbitrap" mass spectrometer. This two-step procedure was applied to fingerprints collected from patients on a maintained dose of the antipsychotic drug quetiapine.
RESULTS: The extraction efficiency of paper spray for two drugs of abuse and metabolites was found to be between 15-35% (analyte dependent). For short acquisition times, the extraction efficiency was found to vary between replicates by less than 30%, enabling subsequent analysis by LC-MS. This two-step process was then applied to fingerprints collected from two patients taking the antipsychotic drug quetiapine, which demonstrates how a negative screening result from paper spray can be resolved using LC-MS.
CONCLUSIONS: We have shown for the first time the sequential analysis of the same sample using paper spray and LC-MS, as well as the detection of an antipsychotic drug from a fingerprint. We propose that this workflow may also be applied to any type of sample compatible with paper spray, and will be especially convenient where only one sample is available for analysis.
Fingerprints have been proposed as a promising new matrix for drug testing. In previous work it has been shown that a fingerprint can be used to distinguish between drug users and non-users. Herein, we look at the possibility of using a fingerprint to distinguish between dermal contact and administration of heroin.
Fingerprint samples were collected from (a) 10 patients attending a drug rehabilitation clinic (b) 50 non-drug users (c) participants who touched 2 mg street heroin, before and after various hand cleaning procedures. Oral fluid was also taken from the patients. All samples were analysed using a liquid chromatography ? high resolution mass spectrometry (LC-HRMS) method validated in previous work for heroin and 6-AM. The HRMS data was analysed retrospectively for morphine, codeine, 6-acetylcodeine and noscapine.
Heroin and 6-AM were detected in all fingerprint samples produced from contact with heroin, even after handwashing. In contrast, morphine, acetylcodeine and noscapine were successfully removed after handwashing.
In patient samples, the detection of morphine, noscapine and acetylcodeine (alongside heroin and 6-AM) gave a closer agreement to patient testimony on whether they had recently used heroin use than the detection of heroin and 6-AM alone.
This research highlights the importance of washing hands prior to donating a fingerprint sample to distinguish recent contact with heroin from heroin use.
Paper spray mass spectrometry is a rapid and sensitive tool for explosives detection but has so far only been demonstrated using high resolution mass spectrometry, which bears too high a cost for many practical applications. Here we explore the potential for paper spray to be implemented in field applications with portable mass spectrometry. This involved (a) replacing the paper substrate with a swabbing material (which we call ?swab spray?) for compatibility with standard collection materials; (b) collection of explosives from surfaces; (c) an exploration of interferences within a/±/0.5/m/z window; and (d) demonstration of the use of high-field assisted waveform ion mobility spectrometer (FAIMS) for enhanced selectivity. We show that paper and Nomex® are viable collection materials, with Nomex providing cleaner spectra and therefore greater potential for integration with portable mass spectrometers. We show that sensitive detection using swab spray will require a mass spectrometer with a mass resolving power of 4000 or more. We show that by coupling the swab spray ionisation source with FAIMS, it is possible to reduce background interferences, thereby facilitating the use of a low resolving power (e.g. quadrupole) mass spectrometer.
Determination of the deposition order of different writing tools is very important for the forensic investigation of questioned documents. Here we present a novel application of two ion beam analysis (IBA) techniques: secondary ion mass spectrometry using MeV ions (MeV-SIMS) and particle induced X-ray emission (PIXE) to determine the deposition order of intersecting lines made of ballpoint pen ink, inkjet printer ink, and laser printer toners. MeV-SIMS is an emerging mass spectrometry technique where incident heavy MeV ions are used to desorb secondary molecular ions from the uppermost layers of an organic sample. In contrast, PIXE provides information about sample elemental composition through characteristic X-ray spectra coming from greater depth. In the case of PIXE, the information depth depends on incident ion energy, sample matrix and self-absorption of X-rays on the way out from the sample to the X-ray detector. The measurements were carried out using a heavy ion microprobe at the Ru?er Boakovi? Institute. Principal component analysis (PCA) was employed for image processing of the data. We will demonstrate that MeV-SIMS alone was successful to determine the deposition order of all intersections not involving inkjet printer ink. The fact that PIXE yields information from deeper layers was crucial to resolve cases where inkjet printer ink was included due to its adherence and penetration properties. This is the first time the different information depths of PIXE and MeV-SIMS have been exploited for a practical application. The use of both techniques, MeV-SIMS and PIXE, allowed the correct determination of deposition order for four out of six pairs of samples.
Lewis Holly-May, Webb Roger, Verbeck Guido F, Bunch Josephine, De Jesus Janella, Costa Catia, Palitsin Vladimir, Swales John G., Goodwin Richard J. A., Sears Patrick, Bailey Melanie Jane (2019) Nanoextraction coupled to liquid chromatography mass spectrometry delivers improved spatially resolved analysis, Analytical Chemistry
American Chemical Society
Direct analyte probed nanoextraction (DAPNe) is a technique that allows extraction of drug and endogenous compounds from a discrete location on a tissue sample using a nano capillary filled with solvent. Samples can be extracted from a spot diameters as low as 6 µm. Studies previously undertaken by our group have shown that the technique can provide good precision (5%) for analysing drug molecules in 150 µm diameter areas of homogenised tissue, provided an internal standard is sprayed on to the tissue prior to analysis. However, without an isotopically labelled standard, the repeatability is poor, even after normalisation to and the spot area or matrix compounds. By application to tissue homogenates spiked with drug compounds, we can demonstrate that it is possible to significantly improve the repeatability of the technique by incorporating a liquid chromatography separation step. Liquid chromatography is a technique for separating compounds prior to mass spectrometry (LC-MS) which enables separation of isomeric compounds that cannot be discriminated using mass spectrometry alone, as well as reducing matrix interferences. Conventionally, LC-MS is carried out on bulk or homogenised samples, which means analysis is essentially an average of the sample and does not take into account discrete areas. This work opens a new opportunity for spatially resolved liquid chromatography mass spectrometry with precision better than 20%.
The radical ring-opening polymerization (RROP) of thionolactones provides access to thioester backbone-functional copolymers but has, to date, only been demonstrated on acrylic copolymers. Herein, the thionolactone dibenzo[c,e]oxepane-5-thione (DOT) was subjected to azobisisobutyronitrile (AIBN)-initiated free-radical homopolymerization, which produced a thioester-functional homopolymer with a glass-transition temperature of 95 °C and the ability to degrade exclusively into predetermined small molecules. However, the homopolymerization was impractically slow and precluded the introduction of functionality. Conversely, the reversible addition?fragmentation chain-transfer (RAFT)-mediated copolymerization of DOT with N-methylmaleimide (MeMI), N-phenylmaleimide (PhMI), and N-2,3,4,5,6-pentafluorophenylmaleimide (PFPMI) rapidly produced well-defined copolymers with the tendency to form alternating sequences increasing in the order MeMI j PhMI
This thesis explores the feasibility of testing for drugs from a fingerprint. Previous publications have reported drug detection in fingerprints from either drug users or after contact with a substance. There are possibilities to exploit these findings either for forensics (where a finger-mark is deposited at a crime scene to give intelligence about a donor) or for drug testing (where fingerprints are deposited under controlled conditions). In forensic science, it may be sufficient to know that a drug has been either handled or ingested within a specific time frame. In contrast, for drug testing, it may be necessary to exclude handling of drugs as a possible source. In either case, it is necessary to understand the significance of detecting a drug or its metabolite in a fingerprint.
This thesis explored the significance of detecting a selection of illicit drugs in fingerprints. In Chapter 4 and Chapter 5, a rapid analysis method based on paper spray high resolution mass spectrometry is developed and validated for cocaine and its metabolite, benzoylecgonine (BZE), and the method is applied to the fingerprints of non-drug users and drug users respectively. As a result, cocaine and BZE were found in samples from both non-drug users (set as environmental cut-off) and drug users. The detection rate from drug users was above 90 % and there were no false positive using this method. Moreover, handwashing involvement became indicative of either ingestion of cocaine OR recent contact with cocaine. In Chapter 6 and 7, imaging mass spectrometry techniques were employed to determine whether contact and ingestion scenarios can be distinguished via spatial distribution of analytes. Those results supported the hypothesis that hot spots would be formed in fingerprints after contact whereas analytes would be evenly distributed in fingerprints after ingestion. The presence of BZE was also used to in distinguishing fingerprint samples from the two scenarios. In Chapter 8 and 9, the paper spray mass spectrometry methodology was expanded to a selection of novel psychoactive substances (NPS) relevant to a prison environment using fingerprints for the first time. The method was applied to the fingerprints of prisoners before and after participants washed their hands. As a result, NPS substances were not detected from any participants, in agreement with their urine testing. Finally, in Chapter 10, the data collected in Chapter 4 and 5 was analysed retrospectively for detection of heroin and 6-AM in fingerprints to explore the possibility of carrying out an untargeted analysis. The sensitivity of the method was not as good as for cocaine and benzoylecgonine (BZE), which led to the lower detection rate of heroin and 6-AM than that of cocaine and BZE. However, this study proved that the paper spray method could still provide qualitative and quantitative results of heroin detection in fingerprints.
This study demonstrates that in the future with a suitable, deployable high resolution mass spectrometer, paper spray mass spectrometry could be used to detect cocaine, its metabolites and NPS for evidential purposes within the confines of a police station.