Cookies

We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Chemistry

Dr Alan Kenwright

Associate Professor (Reader) in the Department of Chemistry
Telephone: +44 (0) 191 33 42095

(email at a.m.kenwright@durham.ac.uk)

Biography

Alan Kenwright got his BSc (1980) from the University of Nottingham, before obtaining an MSc (1981) and PhD (1986) in solid-state NMR at the University of East Anglia under Professor Robin Harris and Professor Ken Packer. 

He did post-doctoral research with Professor Lucian Monnerie at the Ecole Superieure de Physique at Chimie Industrielles, Paris, before taking a position (1987) in the University of Durham Industrial Research Laboratories (UDIRL) doing contract research for industry and forming part of the EPSRC solid-state NMR service.

In 1989 he joined the newly-formed Interdisciplinary Research Centre (IRC) in Polymer Science and Technology at Durham University under Professor Jim Feast as a Research Fellow. During this time he set up the IRC's solution-state NMR facility while maintaining an active interest in solid-state NMR.

Between 1995 and 2008 he was employed as the solution-state NMR manager in the Chemistry Department at Durham University and in 2008 he was promoted to Reader in recognition of his contributions to research and teaching in the department. He has published over 100 research articles and is active in a range of research areas.

Research Interests

Solution-state NMR is one of the most useful techniques for characterising the chemical nature of substances that can be dissolved. The nuclei of certain isotopes possess spin angular momentum ("spin") and the interaction of this spin with radio frequency radiation in the presence of a magnetic field provides a probe, which is uniquely sensitive to the precise distribution of electrons about the nucleus. Information can be obtained not only about the chemical environment of the various nuclei present, but also about their connectivity and topology.

Typical uses of solution-state NMR range from quantitative fingerprinting of complex mixtures through confirmation of product structure with identification of residual solvents and other impurities, to full structural elucidation of unknowns.

The Analytical Centre in the Chemistry Department at Durham University is extremely well equipped for solution-state NMR investigations, having six spectrometers housed in a purpose-built suite of laboratories. The six spectrometers operate at a range of magnetic field strengths corresponding to proton resonance frequencies of 200, 400 (x3), 500, 600 and 700 MHz. (Increased magnetic field strength gives greater resolution and greater sensitivity.)

My research interests centre on the application of NMR techniques to a wide range of chemical problems, with particular interest in NMR characterisation of paramagnetic lanthanide complexes and NMR studies of diffusion.

Paramagnetic Lanthanide complexes

Paramagnetic Lanthanide complexes have found widespread application in recent years both as contrast agents in Magnetic Resonance Imaging (MRI) and as luminescent probes for bio-assay. The characterisation of such complexes by NMR presents particular challenges since the chemical shift range for the protons on ligands complexed to the paramagnetic ion can be in excess of 1000 ppm (compared with the usual range for diamagnetic substances of around 10 ppm).

Diffusion

Pulsed field gradient spin echo NMR is generally the method of choice for diffusion measurements on liquid samples. With modern high field instruments, however, severe problems can arise when it is applied to samples with very high proton concentrations because of the presence of radiation damping. We have recently been involved in developing methods to avoid these problems, and also in developing pulse sequences to extend these measurements to three-dimensional spectra such as HMQC-DOSY.

Selected Publications

Journal Article

Show all publications