Wolfram Meier-Augenstein | |
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Born | September 1959 |
Occupation | Forensic science |
Wolfram Meier-Augenstein is an emeritus professor at Robert Gordon University, Aberdeen, UK, a Fellow of the Royal Society of Chemistry, a member of the advisory board of the journal Rapid Communications in Mass Spectrometry and a member of the editorial board of the journal Isotopes in Environmental and Health Studies for the topics/disciplines ‘stable isotope tracer & methodology’.
Meier-Augenstein was born in September 1959. [1] He completed his studies in Chemistry and Molecular Genetics at the Ruprechts Karl University of Heidelberg, Germany in 1987. He is a certified radiation protection officer and served as such at the Institute of Organic Chemistry from 1986 to 1989. He holds a doctorate in natural sciences (Dr. rer. nat.) awarded by the Ruprechts Karl University of Heidelberg in 1989. The subject of his PhD thesis was the structure/activity relationship of stereoisomers of the Periodic Leaf Movement Factor 1 that triggers the nastic leaf movement of Mimosa pudica . As Feodor-Lynen-Fellow of the Alexander von Humboldt Foundation and PD Fellow of the South African Research Foundation he spent one and a half years as post-doctoral fellow with Prof. B.V. Burger at the Stellenbosch University. Here he synthesised and studied cyclodextrin derivatives used as chiral selectors for selective gas chromatography. From there, his career took him to the University Children's Hospital Heidelberg, the University of California, San Diego, the University of Dundee, the Queen's University Belfast and back to Scotland, first to the James Hutton Institute, Dundee and finally Robert Gordon University, Aberdeen.
While at the University Children's Hospital Heidelberg he designed and developed the first GC(/MS)-C-IRMS instrument for simultaneous compound identification and compound specific isotope analysis of the various constituents of a complex sample. Building this hyphenated MS/IRMS hybrid was supported by Finnigan MAT (as then was) and Dr Willie Brand (Finnigan MAT) who designed and built the interface for splitting the flow from the gas chromatograph in the ratio needed to meet specifications and requirement of both the ion trap mass spectrometer and the Delta S isotope ratio mass spectrometer.
From 2010 to 2014 he served as Director of the Forensic Isotope Ratio Mass Spectrometry Network (FIRMS). [1] [2] while from 2009 to 2013 he was a Council member of the British Association for Human Identification (BAHID). [3] He was one of the scientists consulted by the Garda Síochána investigating the case of the dismembered torso found in the Dublin Royal Canal. [4] This case gained notoriety under the name Scissor Sisters. He was also one of the scientists consulted by the police investigating the Norfolk headless body case. [5] [6]
Most recently Meier-Augenstein was involved with the investigation of the death of Lamduan Armitage dubbed "The Lady of the Hills" and the "Thai Bride". His interpretation of stable isotopic signatures obtained from remains of the murder victim corroborated one line of investigation that the victim might have grown up in Thailand. [7] A subsequently launched public appeal received a response from a Thai family who believed the victim could be their daughter. [8] DNA tests finally confirmed the identity of the victim as Lamduan Armitage, née Seekanya, originally from Thailand who had moved to the UK in 1991. [9]
He is the author of the 2010 book Stable Isotope Forensics, the first textbook dedicated to principles and forensic applications of stable isotope analytical techniques, [10] which since has been extensively up-dated. The second edition, Stable Isotope Forensics - Methods and Forensic Applications of Stable Isotope Analysis, was published in 2018. [11]
On 26 December 2022 Meier-Augenstein appeared in the 2022 Royal Institution Christmas Lectures, with the title 'Secrets of Forensic Science', delivered by Sue Black, Baroness Black of Strome. [12] [13]
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures.
An ion source is a device that creates atomic and molecular ions. Ion sources are used to form ions for mass spectrometers, optical emission spectrometers, particle accelerators, ion implanters and ion engines.
Electron ionization is an ionization method in which energetic electrons interact with solid or gas phase atoms or molecules to produce ions. EI was one of the first ionization techniques developed for mass spectrometry. However, this method is still a popular ionization technique. This technique is considered a hard ionization method, since it uses highly energetic electrons to produce ions. This leads to extensive fragmentation, which can be helpful for structure determination of unknown compounds. EI is the most useful for organic compounds which have a molecular weight below 600 amu. Also, several other thermally stable and volatile compounds in solid, liquid and gas states can be detected with the use of this technique when coupled with various separation methods.
Electrospray ionization (ESI) is a technique used in mass spectrometry to produce ions using an electrospray in which a high voltage is applied to a liquid to create an aerosol. It is especially useful in producing ions from macromolecules because it overcomes the propensity of these molecules to fragment when ionized. ESI is different from other ionization processes since it may produce multiple-charged ions, effectively extending the mass range of the analyser to accommodate the kDa-MDa orders of magnitude observed in proteins and their associated polypeptide fragments.
Secondary-ion mass spectrometry (SIMS) is a technique used to analyze the composition of solid surfaces and thin films by sputtering the surface of the specimen with a focused primary ion beam and collecting and analyzing ejected secondary ions. The mass/charge ratios of these secondary ions are measured with a mass spectrometer to determine the elemental, isotopic, or molecular composition of the surface to a depth of 1 to 2 nm. Due to the large variation in ionization probabilities among elements sputtered from different materials, comparison against well-calibrated standards is necessary to achieve accurate quantitative results. SIMS is the most sensitive surface analysis technique, with elemental detection limits ranging from parts per million to parts per billion.
Koichi Tanaka is a Japanese electrical engineer who shared the Nobel Prize in Chemistry in 2002 for developing a novel method for mass spectrometric analyses of biological macromolecules with John Bennett Fenn and Kurt Wüthrich.
Gas chromatography–mass spectrometry (GC–MS) is an analytical method that combines the features of gas-chromatography and mass spectrometry to identify different substances within a test sample. Applications of GC–MS include drug detection, fire investigation, environmental analysis, explosives investigation, food and flavor analysis, and identification of unknown samples, including that of material samples obtained from planet Mars during probe missions as early as the 1970s. GC–MS can also be used in airport security to detect substances in luggage or on human beings. Additionally, it can identify trace elements in materials that were previously thought to have disintegrated beyond identification. Like liquid chromatography–mass spectrometry, it allows analysis and detection even of tiny amounts of a substance.
In mass spectrometry, matrix-assisted laser desorption/ionization (MALDI) is an ionization technique that uses a laser energy-absorbing matrix to create ions from large molecules with minimal fragmentation. It has been applied to the analysis of biomolecules and various organic molecules, which tend to be fragile and fragment when ionized by more conventional ionization methods. It is similar in character to electrospray ionization (ESI) in that both techniques are relatively soft ways of obtaining ions of large molecules in the gas phase, though MALDI typically produces far fewer multi-charged ions.
In chemistry, isotopologues are molecules that differ only in their isotopic composition. They have the same chemical formula and bonding arrangement of atoms, but at least one atom has a different number of neutrons than the parent.
Fast atom bombardment (FAB) is an ionization technique used in mass spectrometry in which a beam of high energy atoms strikes a surface to create ions. It was developed by Michael Barber at the University of Manchester in 1980. When a beam of high energy ions is used instead of atoms, the method is known as liquid secondary ion mass spectrometry (LSIMS). In FAB and LSIMS, the material to be analyzed is mixed with a non-volatile chemical protection environment, called a matrix, and is bombarded under vacuum with a high energy atomic beam. The atoms are typically from an inert gas such as argon or xenon. Common matrices include glycerol, thioglycerol, 3-nitrobenzyl alcohol (3-NBA), 18-crown-6 ether, 2-nitrophenyloctyl ether, sulfolane, diethanolamine, and triethanolamine. This technique is similar to secondary ion mass spectrometry and plasma desorption mass spectrometry.
Sinapinic acid, or sinapic acid (Sinapine - Origin: L. Sinapi, sinapis, mustard, Gr., cf. F. Sinapine.), is a small naturally occurring hydroxycinnamic acid. It is a member of the phenylpropanoid family. It is a commonly used matrix in MALDI mass spectrometry. It is a useful matrix for a wide variety of peptides and proteins. It serves well as a matrix for MALDI due to its ability to absorb laser radiation and to also donate protons (H+) to the analyte of interest.
Isotope-ratio mass spectrometry (IRMS) is a specialization of mass spectrometry, in which mass spectrometric methods are used to measure the relative abundance of isotopes in a given sample.
The history of mass spectrometry has its roots in physical and chemical studies regarding the nature of matter. The study of gas discharges in the mid 19th century led to the discovery of anode and cathode rays, which turned out to be positive ions and electrons. Improved capabilities in the separation of these positive ions enabled the discovery of stable isotopes of the elements. The first such discovery was with the element neon, which was shown by mass spectrometry to have at least two stable isotopes: 20Ne and 22Ne. Mass spectrometers were used in the Manhattan Project for the separation of isotopes of uranium necessary to create the atomic bomb.
Surface-enhanced laser desorption/ionization (SELDI) is a soft ionization method in mass spectrometry (MS) used for the analysis of protein mixtures. It is a variation of matrix-assisted laser desorption/ionization (MALDI). In MALDI, the sample is mixed with a matrix material and applied to a metal plate before irradiation by a laser, whereas in SELDI, proteins of interest in a sample become bound to a surface before MS analysis. The sample surface is a key component in the purification, desorption, and ionization of the sample. SELDI is typically used with time-of-flight (TOF) mass spectrometers and is used to detect proteins in tissue samples, blood, urine, or other clinical samples, however, SELDI technology can potentially be used in any application by simply modifying the sample surface.
Soft laser desorption (SLD) is laser desorption of large molecules that results in ionization without fragmentation. "Soft" in the context of ion formation means forming ions without breaking chemical bonds. "Hard" ionization is the formation of ions with the breaking of bonds and the formation of fragment ions.
The mass recorded by a mass spectrometer can refer to different physical quantities depending on the characteristics of the instrument and the manner in which the mass spectrum is displayed.
In geochemistry, paleoclimatology, and paleoceanography δ13C is an isotopic signature, a measure of the ratio of the two stable isotopes of carbon—13C and 12C—reported in parts per thousand. The measure is also widely used in archaeology for the reconstruction of past diets, particularly to see if marine foods or certain types of plants were consumed.
The term stable isotope has a meaning similar to stable nuclide, but is preferably used when speaking of nuclides of a specific element. Hence, the plural form stable isotopes usually refers to isotopes of the same element. The relative abundance of such stable isotopes can be measured experimentally, yielding an isotope ratio that can be used as a research tool. Theoretically, such stable isotopes could include the radiogenic daughter products of radioactive decay, used in radiometric dating. However, the expression stable-isotope ratio is preferably used to refer to isotopes whose relative abundances are affected by isotope fractionation in nature. This field is termed stable isotope geochemistry.
Isotopic reference materials are compounds with well-defined isotopic compositions and are the ultimate sources of accuracy in mass spectrometric measurements of isotope ratios. Isotopic references are used because mass spectrometers are highly fractionating. As a result, the isotopic ratio that the instrument measures can be very different from that in the sample's measurement. Moreover, the degree of instrument fractionation changes during measurement, often on a timescale shorter than the measurement's duration, and can depend on the characteristics of the sample itself. By measuring a material of known isotopic composition, fractionation within the mass spectrometer can be removed during post-measurement data processing. Without isotope references, measurements by mass spectrometry would be much less accurate and could not be used in comparisons across different analytical facilities. Due to their critical role in measuring isotope ratios, and in part, due to historical legacy, isotopic reference materials define the scales on which isotope ratios are reported in the peer-reviewed scientific literature.