Professor Edward W. Randall
Emeritus Professor
BA BSc DPhil MA (Oxon) CChem FRSC
School of Biological & Chemical Sciences
Queen Mary, University of London
Mile End Road
London
E1 4NS
Tel: +44 (0) 20 7882 6352
email: E.W.Randall@qmul.ac.uk
Research Interests
My consistent interest has been the development of multinuclear magnetic resonance techniques (both direct and indirect, using double resonance methods) and their application
to many areas in chemistry (inorganic, organic, organometallic,
polymeric, structural, biochemical, biomedical), and has more recently
embraced NMR imaging, particularly of solids (organic polymers and materials of all sorts), and liquids in solids.
The group had the first commercial Fourier
Transform (FT) NMR Spectrometer in the UK and obtained the first FT
spectra of 15 N and 2 H at natural abundance. Other nuclei studied
include 13 C, 14 N, 17 O and 31 P. Studies of oriented samples gave
detailed molecular geometries. There were important collaborations with
QMC colleagues in the areas of organometallic and peptide chemistry, the
NMR of paramagnetic compounds in the field of shift and relaxation
reagents.
In the last decade the group's efforts have turned to studies of the solid state and to imaging studies, each
with particular reference to soils and porous materials. We used a large probe on the Varian Imaging Spectrometer for stray
field (STRAFI) -imaging. This is only the second STRAFI-system in the
UK, and about the fourth operational world wide. It was unique in having a
large probe of 5 cm diameter, suitable for soil, or sand.
STRAFI Imaging.
In 1991 Dr. Paul Kinchesh and I, together
with Dr. Klaus Zick of Bruker, were the first UK scientists to use the
powerful STRAFI technique of Samoilenko, and showed that
(i) image distortions produced by magnetic susceptibility variations
are greatly reduced in STRAFI-images for example of water in soil and
(ii) any magnetically active nucleide, including quadrupolar
nucleides, can be imaged by STRAFI-techniques even in the solid state,
and even if the sample is paramagnetic.
Consequently we can for example investigate
both 'bound' and 'free water' in any material. The range of industrial
and environmental applications is immense.
The group now has more than 30 STRAFI-publications.
The solid state 1 H and 31 P imaging of bone
and biomedical materials should prove to be important medically. We have
initiated work on 7 Li and 31 P imaging of glasses and ceramics, some
paramagnetic, with Dr. I. Abrahams. Currently Dr. Alasdair Preston and I are collaborating with Drs. Richard Whalley and Nigel Bird at The Silsoe Research Institute
in studying the behaviour of water in soil at different matric
potentials with BBSRC support. We are extending the STRAFI-method to
include the flow of oil and water in rocks. With Dr. Teresa Nunes' group
in Lisbon we have succeeded in the first NMR imaging of both ice and
heavy ice. A new project is the STRAFI-NMR study of dental materials
being developed in the Department of Biomaterials in Dentistry with
Professors G. Pearson, M. Braden, and Dr. M. Patel.
Organic Matter in Soil.
Meanwhile Dr. Nathalie Mahieu
and I continued, also with BBSRC funding, with our spectroscopic
studies of organic matter in soils from all over the world, in
collaboration with Professor Powlson's soil group at the Rothamsted Research Station. Dr. Mahieu maintains a data-base of published NMR spectra of soils which can be found here
We have investigated 13 C, 15 N and 31 P
resonances in both the solid state and in liquid extracts from soil.
Recently we have characterised solid fractions obtained via a Rothamsted
density-fractionation procedure, giving a free light fraction and intra-aggregate
light fractions. The results will be used as the building blocks in
models of the turnover of soil organic matter. We are also comparing the
information obtained from NMR with that from several other techniques
including 'wet' chemical methods, py-GC/MS, FTIR, GC/MS analysis of
lipids, in collaboration with Professor R. Evershed's Group at the
University of Bristol.
Current Projects
- New Methods in NMR imaging ( Stray Field Imaging and Indirect Methods) including STRAFI-work on a 19.6 T system at the National High Field Laboratory in Tallahassee.
- Gamma-platform simulations of STRAFI-NMR ( http://gamma.magnet.fsu.edu )
- Stray Field imaging of materials and
porous solids: soils, rocks, cements, glasses, ceramics, organic
polymers, bones, and catalytic materials
- STRAFI- imaging and Spectroscopic Studies of Dental Materials.
- Solid State NMR spectroscopic studies of organic matter in soils
- Solution state studies of soil extracts using multinuclear and multidimensional high field (14.1T) techniques.
Collaborations & Funding
We have had collaborations with
STRAFI-groups in Surrey (Professor Peter McDonald, Dr. Duncan Gillies),
Moscow (Professor Andrei Samoilenko) and Lisbon (Dr. Teresa Nunes),
aided by an EU grant. Additionally we are helping develop
STRAFI-facilities on high field systems at the National High Magnetic
Field Laboratory (NHMFL) in Tallahassee such as the 19.6 Tesla magnet.
Also we collaborate with Dr. Scott Smith at the NHMFL on extensions of
the Gamma-platform computing facility to STRAFI-problems. We have shared
BBSRC funding for soils work both with the Rothamsted and Silsoe
Research Institutes, and with the University of Bristol (for Mass
Spectrometry investigations). Authors in the publications list come from
Bulgaria, France, Italy, Portugal, the Philippines, Russia, and the
USA. We have also received EPSRC travel funding.
Recent Publications
The Early NMRDG: a personal Memoir , Royal Society of Chemistry, Historical Group, 2009, 18-26.
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