From the box to the wardrobe
Thermo Electron ICP-OES SPECTROMETER IRIS Intrepid II (2004)
Quantometer
Until the introduction of chromatography, optical methods were historically the most frequently applied in the environmental, food and clinical fields. Absorption, based on the measurement of colour intensity, was the preferred method as it was the easiest one to develop instruments for (spectrophotometer, photometer, colormeter). Emission methods were developed at a later stage, starting from simple qualitative flame analysis methods. The historic evolution of these methods began with flame, arch or spark source emission spectrometers, depending on the element to be determined. There is a hundred degrees difference in the temperatures of the three aforementioned methods of excitement, therefore each produces excitement conditions, which are energetically very different and therefore selective according to the element to be excited. The quantometer is both the most versatile and precise version (accuracy remains substantially the same) of the emission spectrometer; depending on applied engineering structures, it is possible to carry out analyses of the same sample and even up to several dozen samples at the same time. Obviously this characteristic has required some sacrifice in terms of size: devices are over a metre in length. Recently there have been further developments concerning the transportability of quantometers.
Analytical robot
As research has progressed, the evolution of instrumental analytical chemistry has enabled the creation of instruments both for in situ and continuous analysis. However, this has never been considered as an end objective as in situ analysis may imply difficult or even dangerous environmental conditions for the experimenter, and continuous analysis requires careful monitoring of the obtained results. Both difficulties have been overcome with the introduction of analytical robots, which can be operated without a technician and can also elaborate measurement data. In this way it is possible to continuously document and monitor hostile environments such as volcanoes, perennial glacial sites, marine abysses.
Nuclear Magnetic Resonance (NMR)
Nuclear magnetic resonance is a material investigation technique based on the measurement of the precession of the spin of protons or other nuclei with magnetic momentum, when subjected to a magnetic field. As an investigation technique, magnetic resonance has applications in medicine, chemistry, petrography and applied geophysics.
It was independently discovered in 1946 by the physicians Felix Bloch and Edward Purcell, who received the Nobel Prize for Physics in 1952. Between 1950 and 1970 it was mainly used in the analysis of molecular chemistry and the structure of materials. In 1949 the American company Varian obtained a patent for the use of MNR in measuring the earth's magnetic field. In 1960 Brown and Gamsom of Chevron made the first experimental recording of "NMR Logging", in a well for oil research, and in 1978 Schlumberger introduced the first standard logging instrument called NML (Nuclear Magnetic Logging).
Raymond Vahan Damadian was the inventor of the first ever magnetic resonance device for the study of the body, an American who graduated in medicine and specialised in nephrology, biophysics and biochemistry. Damadian studied the spectrum of sodium and potassium in animal cells and created a device capable of capturing the radio emissions of atoms subjected to a magnetic field and solicited by radio frequencies. In 1971 he demonstrated that tumour cells in rats have a greater relaxation time compared to healthy cells, although his intention was not as much the production of morphological images, but rather quantitative data on tissue characteristics. After a few studies he proposed that the scientific world should take magnetic resonance into consideration for the detection of diseases in man. In 1972 he patented the first MR device for the study of the human body, however despite some public interest, his work was discredited by his colleagues.
On 16th March 1973, the physicist Paul C. Lauterbur obtained the first ever MR images of a sample object consisting of small tubes containing water. For the reconstruction of the image, he had the idea of using magnetic field gradients in order to receive information on the position of atoms. The image was created using a rear projection technique, similar to the one used in CAT. He published an article: "Image formation by induced local interaction; examples employing magnetic resonance" in the scientific magazine Nature. Later, he called this technique "zaeumatography", although initially it mustered little interest in the scientific world. It was the step, which determined the passage from the measurement of single zones to measurement with spatial localisation, therefore the foundation of current clinical imaging.
Although it was believed that it would not have damaging effects on people, the use of magnetic resonance was yet to be experimented on human beings. The first images of a finger were produced in 1976 by Peter Mansfield; in 1977 Paul Bottomley and Waldo Hinshaw produced the image of a wrist; in 1978 Electrical and Musical Industries (EMI) produced the first image of cerebral parenchyma. In 1975 Richard Ernst proposed a process of phase codification and codification of radio frequencies and the introduction of the Fourier's transform in the analysis of data obtained. The intuition of Ernst was used in 1980 by Edelstein and his collaborators. RF codification led to a reduction in the time required to acquire a single image to approximately five minutes. Over the years, new reconstruction techniques considerably reduced time and already in 1986 images could be produced in around five seconds. In the same year, a few scientists developed the nuclear magnetic resonance microscope, which was capable of achieving a resonance of almost 10 µm on a sample of approximately 1 centimetre. During the early eighties, a few groups associated with manufacturers began producing magnetic resonance devices for in vivo studies for the study of the human body. In England a few groups began working on such devices and the first one in Europe was installed by Picker in 1983 at the Department of Diagnostic Radiology at the University of Manchester Medical School. Thanks to EPI technique, in 1987 real time images of a single cardiac cycle were obtained for the first time. In the same year Charles Dumoulin distinguished himself for his discoveries in angiography: he obtained angioresonance images without the use of contrast liquid. In 1991, Richard Ernst received the Nobel Prize for Chemistry for his results on pulsed Fourrier transform in MR investigation. The development of functional MR (fMRI) first began in 1992, focused on the construction of a map of the human brain, and was based on responses to external stimuli and the identification of cerebral regions responsible for the control of thought and movement. In 1994, researchers of Stony Brook and Princeton Universities in the New York State (USA) successfully performed imaging experiments with hyperpolarised gas 129Xe for respiratory studies. In 2003 Paul C. Lauterbur from the University of Illinois and Peter Mansfield from Nottingham University were awarded the Nobel Prize in Medicine for their discoveries in the field of magnetic resonance imaging.
