The latest edition of the European Pharmacopoeia on ultraviolet and visible spectroscopy has become mandatory as of 1 January 2020, so those of you who need to comply with its requirements will find this of particular interest. Nathan and John pick apart the significant changes with a view to their practical application for instrument users. Cells, control of equipment performance, wavelength accuracy, absorbance accuracy, photometric linearity, stray light and resolution, system suitability and reference materials are all covered.
Tony and Lutgarde Buydens give us an update on the planning for the major EuroAnalysis 2021 conference, which is being held in Nijmegen, the Netherlands, at the end of August 2021. At this stage, they are keen to gather suggestions from readers on topics they would like to see covered. Groups are also invited to consider hosting their own event under the EuroAnalysis 2021 banner.
The authors describe work they are doing to develop a green methodology to determine soil organic matter. If the World’s population is to be fed in the future, improvements to agricultural productivity are required and soil fertility will be key to this. Current methodologies are time-consuming and expensive, but visible-near infrared spectroscopy has the potential to replace them.
Some compliance requirements would seem to make impossible demands on the performance specification of “fitness for purpose” for ultraviolet spectrometers; Chris and John unravel what’s going on.
It is not every issue that one of our articles starts with a quotation in medieval English, and it is appropriate as two of our articles cover the use of spectroscopy in cultural heritage. This is yet another field where the rich information provided by spectroscopy, along with its non-destructive nature (for many techniques), portability and ability to generate chemical images make it the answer to many questions. Kate Nicholson, Andrew Beeby and Richard Gameson are responsible for the medieval English at the start of their article “Shedding light on medieval manuscripts”. They describe the general use of Raman spectroscopy for the analysis of historical artefacts, and, in particular, their work on medieval European manuscripts and 18th century watercolour pigments. They stess the importance of checking the actual laser power density to avoid damage to priceless artefacts.
To ensure that the removal and treatment of our sewerage meets increasingly high standards, it is important to be able to monitor the water online both to provide timely information and also to establish changing patterns over days, weeks and seasons. In their article “On-line monitoring for improved wastewater system management: applications of ultraviolet/visible spectroscopy”, Rita Brito, Rita Ribeiro, Tatiana Arriaga, Catarina Leitão, Nìdia Lourenço, Filipa Ferreira and Helena Pinheiro demonstrate the value of on-line UV/vis spectroscopy for wastewater quality monitoring in decentralised wastewater treatment and for spectral on-line monitoring of key quality parameters at the inlet to wastewater treatment plants.
In this Tony Davies Column, we learn about “Automated detection of counterfeit drugs using multimodal spectroscopy and advanced web-based software platforms”. The German authorities have commissioned the development of a multi-modal, transportable inspection system, including intelligent data processing and evaluation, for fast spectroscopic recognition of illicit drugs and counterfeit medicines. This is described in the column.
The analysis of turbid samples is increasingly important, not least due to their widespread occurrence in natural samples. Dmitry Khoptyar, Sören Johansson, Staffan Strömblad and Stefan Andersson-Engels show “Broadband photon time-of-flight spectroscopy as a prospective tool in biomedicine and industrial process and quality control”. The authors describe their recent development of a broadband spectrometer for evaluation of absorption and scattering spectra of very diverse turbid materials in the visible and close-near infrared (NIR) regions and its application with milk, cheese and paper samples.
With the threat of climate change, understanding the workings of our atmosphere is of crucial importance. Ozone is the most important trace gas in the stratosphere and troposphere and it is monitored by both satellite-borne and ground-based instruments. Accurate knowledge of ozone absorption cross-sections is vital for this work and described in this article.
BBCEAS is a new cavity-based absorption technique that uses broadband sources rather than lasers. This offers potential improvements in signal-to-noise but often lower spectral resolution compared to techniques where the laser wavelength is scanned. The article concentrates on liquid-phase applications, an interesting new area since most cavity-based absorption studies have been performed on gas-phase species up to now.
The intense development of industrial and urban areas in the absence of accurate measures to control pollution sources is often the cause of several environmental problems: dispersed and undetected chemical waste problems, in particular trace elements such as heavy metals, may cause freshwater, soil and water-table contamination. Such events are rarely detectable by sporadic analyses on water samples, since trace element concentrations are often below the instrumental detection limits and/or quickly change in space and time.
This short review shows that UV/visible spectroscopy plays a key role in the discrimination of colour in the forensic analysis of fibres and inks. The application of chemometrics, however, is vital in many cases to enhance such discrimination and to put it on a quantitative basis so providing objective justification for the conclusions of the analyst.
Burgess Analytical Consultancy Limited, “Rose Rae”, The Lendings, Startforth, Barnard Castle, Co. Durham, DL 12 9AB, UK
Starna Scientific Ltd, 52–54 Fowler Road, Hainault Business Park, Hainault, Essex, IG6 3UT, UK/p>
As the column title rightly suggests Quality does Matter. The authors look at the major changes that have taken place over the last 50 years in four key areas: The National Metrology Institutes (NMIs), the instrument manufacturers, the user base and the globalisation of regulation through international regulatory bodies.
Thin polymer layers on solid substrates are of high technological importance due to their increasing potential for applications in electronics, sensors, nanotechnology and biotechnology. Appropriate characterisation methods are necessary for the design and analysis of devices made using such materials. This review article focuses upon presenting the many analytical possibilities for quantitative evaluation of the optical constants and thickness of polymer layers by combined application of spectroscopic ellipsometry (SE) in the visible (vis) and infrared (IR) spectral range.
UV/vis reflection spectroscopy is a practical method to investigate pulp ageing, especially when reflectance spectra are converted to absorbance (k/s) spectra. Even if detailed reaction paths cannot be solved with this technique alone, it provides a very fast and simple method to study the changes in the concentrations of certain important pulp components during ageing. In addition, the concentrations of these components have been studied also in other pulp processes, such as mechanical and chemical pulp bleaching.
G. Langergraber,a J. van den Broeke,b,* W. Lettlb and A. Weingartnerb
aInstitute for Sanitary Engineering and Water Pollution Control, BOKU - University of Natural Resources and Applied Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria. E-mail: [email protected]
As the first compact on-line instruments for use in the field have been on the market for several years, this article reviews their capabilities and applications.
Richard P. Tuckett
School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK