Informing Spectroscopists for Over 40 Years

Articles

Spotlight on nuclear magnetic resonance: a timeless technique

Clemens Anklin gives a short history of the commercial and technical development of NMR. From the first measurement of nuclear spin in 1937 by Rabi and his 1943 Nobel Prize to recent developments in small NMR spectrometers and instrument company changes.

Dates and fates of pyrogenic carbon: using spectroscopy to understand a “missing” global carbon sink

Research into climate change takes many directions, but storing carbon or understanding its release from stores is extremely important. Pyrogenic carbon comes from the incomplete burning of biomass, and can be natural, e.g. wild fires, or man-made, e.g. the production of charcoal. The authors describe the uses of a range of spectroscopy techniques to understand the molecular structure of pyrogenic carbon and its role in the global carbon cycle.

The emerging use of magnetic resonance imaging to study river bed dynamics

Fine sediments, often due to run-off from the land, can clog the surface and sub-surface spaces in gravel beds used by spawning fish to lay their eggs and by aquatic insects. Without an adequate flow of oxygenated water, the eggs and insects die. Heather Haynes, Susithra Lakshmanan, Anne-Marie Ockelford, Elisa Vignaga and William Holmes tells us about this in “The emerging use of magnetic resonance imaging to study river bed dynamics”. They have studied the infiltration of various sediments into model gravel beds both outside and flowing through a MRI instrument! They conclude that MRI “provides an exciting opportunity to unravel a plethora of processes relevant to wider environmental science”.

Dating fossil teeth by electron paramagnetic resonance: how is that possible?

Mathieu Duval raises the question “Dating fossil teeth by electron paramagnetic resonance: how is that possible?”. Whilst we are all familiar with 14C dating, the use of EPR is less well known. In fact, there are less than 10 laboratories in the world able to carry out EPR dating of fossil teeth!

Rheo-nuclear magnetic resonance spectroscopy: a versatile toolbox to investigate rheological phenomena in complex fluids

“Rheo-nuclear magnetic resonance spectroscopy: a versatile toolbox to investigate rheological phenomena in complex fluids” is Claudia Schmidt’s topic. Rheology is an important science, and NMR has a number of uses within it. However, challenges remain for the simultaneous measurement of rheological and NMR parameters.

Nuclear magnetic resonance-based approach to fruit characterisation: the case studies of kiwifruits and peaches

Many analytical methods have been used to control the quality, authenticity and origin of fresh fruit. NMR methodologies yield a comprehensive metabolic profile, provide direct structural information regarding individual metabolites in the mixture and also give information regarding the water state in the tissue. This is useful in discriminating various fruits varieties, in investigating nutritional properties, in monitoring the development of the fruit and in assessing the optimum harvesting time.

The use of nuclear magnetic resonance as an analytical tool in the characterisation of dispersion behaviour

Nuclear magnetic resonance (NMR) spectroscopy is one of the most powerful analytical tools used to probe details of molecular structure and dynamics. It requires very high magnetic fields and, hence, generally uses extremely large, powerful magnets. The advent of small, powerful magnets has allowed much less expensive low resolution NMR instrumentation to be designed, making it feasible to measure commercially important characteristics of dispersion behaviour and performance, including the wetted surface area of particulate suspensions and emulsion droplet size. An important additional practical application is the ability to determine competitive adsorption and/or displacement of polymers and surfactants at interfaces. This article presents a brief overview of these new approaches together with an example of each measurement.

Rapid NMR screening of total aldehydes to detect oxidative rancidity in vegetable oils and decorative cosmetics

Dirk Lachenmeier, Marina Gary, Yulia Monakhova, Thomas Kuballa and Gerd Mildau describe “Rapid NMR screening of total aldehydes to detect oxidative rancidity in vegetable oils and decorative cosmetics”. Lipid oxidation produces rancid products, which are both unpleasant and potentially toxic. The authors describe the use of NMR to screen food and cosmetic products. Whilst, vegetable oils were generally found to be in good condition, German women may wish to be careful of their lipstick, especially if they have had kept it for a while!

A toast to dynamic NMR spectroscopy: towards a better comprehension of palatable emulsions

An NMR tour of Mediterranean anise-flavoured alcoholic beverages.

DOSY NMR, a new tool for fake drug analyses

Stéphane Balayssac,a Véronique Gilard,a Marc-André Delsucb and Myriam Malet-Martinoa

aUniversité de Toulouse, UPS, Laboratoire de Synthèse et Physico-Chimie de Molécules d’Intérêt Biologique (SPCMIB), Groupe de RMN Biomédicale, 118 route de Narbonne, 31062 Toulouse cedex 9, France
bInstitut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), 1 rue Laurent Fries, BP 10142, 67404 Illkirch, France

A short history of magnetic resonance imaging

A brief history and personal recollection of the development of magnetic resonance imaging (MRI).

Quantitative NMR spectroscopy in the quality evaluation of active pharmaceutical ingredients and excipients

The purpose of this short review article is to highlight some capabilities of qNMR spectroscopic methods in drug quality evaluation, indicating that qNMR spectroscopy should be more often applied when chromatographic methods are not working effectively.

Nuclear magnetic resonance: stepping up to the PAT challenge

Our focus here is analytical procedures and the role of nuclear magnetic resonance (NMR) in particular. These have, until now, largely relied on conventional chromatography, and vibrational spectroscopy—infrared (IR), Raman and near infrared (NIR) spectroscopy. In spite of inherent difficulties with peak assignment and reliable quantification, vibrational spectroscopy has been used to derive information on reaction progression to impart fundamental understanding. This article sets out a wider scope to show how NMR can play a key role. Furthermore, NMR integrates well with established procedures to provide a suite of useful technologies that make the PAT challenge tractable.

The power of electron paramagnetic resonance spectroscopy in pharmaceutical analysis

Helen Williams and Mike Claybourn

AstraZeneca, Silk Road Business Park, Macclesfield, Cheshire, SK10 2NA, UK

The prediction of 1H NMR chemical shifts in organic compounds

Raymond J. Abraham and Mehdi Mobli

Chemistry Department, The University of Liverpool, PO Box 147, Liverpool L69 3BX, UK

Highlight Article: LC-NMR/MS

Steve Down

HD Science Limited, 16 Petworth Avenue, Toton, Nottingham NG9 6JF, UK

Olive oil as seen by NMR and chemometrics

Luisa Mannina,a,b Anatoli P. Sobolevb and Annalaura Segreb

aUniversity of Molise, Faculty of Agriculture, 86100 Campobasso, Italy
bInstitute of Chemical Methodologies, CNR, 00016 Monterotondo Staz., Rome, Italy

Superconducting magnets: at the heart of NMR

Alan Street

Technical Director, Oxford Instruments Superconductivity

NMR: still listening to whispering hydrogens? What else do they tell us 50 years after their discovery?

It is now more than fifty years ago that Felix Bloch and Edward Mills Purcell independently discovered a phenomenon called nuclear magnetic resonance (NMR). Only a few years later, in 1952, both received the Nobel Laureate Physics award for this discovery. Purcell and Bloch were the first to “listen” to the whisperings of hydrogen. They eventually obtained an NMR spectrum representing the different “pitches” of the nuclei, a property, which reflects the physico–chemical (electronic) neighbourhood of the nucleus.