Dr Martyn G Boutelle is a Reader in Biomedical Sensor Engineering. He trained at Imperial College gaining a PhD in electrochemistry fromm the Department of Chemistry. He then moved to Physiology at the University of Oxford where he worked in the interdisciplinary area of in vivo monitoring of the brain using electrochemical sensors. His work there lead to an interest in brain metabolism, and monitoring extracellular neurochemistry with high time resolution by use of microelectrodes and on-line microdialysis. This was extended to clinical monitoring of the brain in 1995 when he moved to the Department of Chemistry, King’s College where he was a Lecturer and then a Reader in Biomedical Analysis.   He now works closely with neurosurgeons at King’s College Hospital, and is a founder member of COSBID (www.cosbid.org), an grouping of clinicians and fundamental scientists interested in the role of spontaneous brain depolarisations in the maturation of brain injury.

Current Projects

My group is interdisciplinary covering areas from fundamental

electrochemistry through the analytical science and engineering required to build biosensors for biomedical use, to the neuroscience needed to understand the mechanisms of brain injury. Clinical measurements are through a long-term collaboration with Professor Anthony Strong of King’s College Hospital.

1   Development of a high time resolution monitoring system for clinical use during neurosurgery and critical care monitoring of traumatic brain injury. 
The brain is sampled using a microdialysis probe (www.microdialysis.se). The microdialysate stream is analysed on-line.

     The targets for the system are

          (a) measurement of 4 key neurochemicals each 30s

          (b) continuous measurement of microdialysis flow rate (0.1 – 2 ml / min)

          (c) good stability  over 5 days clinical monitoring period.

2   Development of a low volume continuously reading potassium sensor.
 There are particular challenges to monitoring transient changes in potassium against a constant background level in a sub-microlitre flow cell. However, this is an important neurochemical marker linking the timescales of brain depolarisations measured electrically and other neurochemical changes.

3   Microfluidic biosensor systems for the continuous analysis of neurochemicals in clinical microdialysis streams.
The low volumes and precise geometries of microfabricated devices are ideal environments for microelectrode based biosensors. The removal of switching valves and high pressure pumps will allow devices to be placed much nearer to the sampling probe.  This will greatly shorten the time between the occurrence of an event in the brain tissue and its detection and hence provide faster ‘neurochemical feedback’ for the neurosurgical team.

4   Detection and characterisation of spontaneous depolarisation of brain activity. 
We have detected for the first time waves of ‘spreading depression’ moving across the human cortex. These SD waves seem to originate from the core damaged tissue and represent a substantial challenge to surrounding ‘penumbral’ tissue. In experimental models we have used rapid sampling microdialysis to obtain a dynamic signature of metabolic changes that characterise such spreading waves. In brain injury patients we do see dynamic metabolic changes, and we are in the process of characterising the SD waves that we see. Excitingly preliminary results show a strong correlation between the number of SD events and the fall in extracellular brain glucose levels. This research now feeds an international collaboration of clinicians and fundamental scientists (www.cosbid.org) that we formed in 2003.

5   Monitoring of brain metabolism during aneurysm surgery.
Although in many ways such acute measurements are not ideal for microdialysis, we obtain very informative data by using our rapid sampling microdialysis systems to provide a ‘metabolic commentary’ to the neurosurgeon during aneurismal surgery. We exploit the short time between tissue change and on-line measurement to feedback to the clinical team during the operation an assessment of tissue vulnerability.

Research Background
 

Read chemistry, at Imperial College and then worked under the supervision of Professor John Albery FRS in the Department of Chemistry to be awarded a Ph.D in Electrochemistry. He then moved to the University Laboratory of Physiology, Oxford working with Dr Marianne Fillenz on the use of electrochemical sensors to study physiologically stimulated release of neurochemicals. This work continued in the New Chemistry Laboratory, Oxford and was extended to microelectrodes working with Professor Allen Hill FRS. He was also an EP Abraham research Fellow at Green College Oxford, In 1995 he was appointed to a lectureship in Physical and Analytical Chemistry and then a readership in Biomedical Analysis in the Department of Chemistry, King’s College London. In 2005 he returned to Imperial College in the Department of Bioengineering. 

Selected references

1     Transient Changes in cortical glucose and lactate levels associated with peri-infarct depolarization, studies with rapid sampling microdialysis. SE Hopwood, MC Parkin, EL. Bezzina, MG Boutelle, A. J. Strong. J. Cereb Blood Flow and Metab. (2005), 25(3), 391-401

2     Dynamic changes in brain glucose and lactate in pericontusional areas of the human cerebral cortex, monitored with rapid sampling on-line microdialysis. MC Parkin, SE Hopwood, DA Jones, H Landolt, M Fabricius, M Lauritzen, MG Boutelle, AJ Strong  J Cereb Blood Flow and Metab. (2005), 25(3), 402-413.

3     Resolving dynamic changes in brain metabolism using biosensors and on-line microdialysis. M. C. Parkin S. E. Hopwood, A. J. Strong  and M. G. Boutelle, Tr AC, (2003), 22, 487-497.

4     Glutamate infusion coupled with hypoxia has a neuroprotective effect. J Ros, D. A. Jones,N. Pecinska, B alessandri, M. G. Boutelle, H. Landolt, M Fillenz, J Neuroscience Methods, (2002), 119, 129-133.

5     Spreading and synchronous depressions of cortical activity in the acutely injured human brain. A J. Strong, M Fabricius, M G. Boutelle, S J. Hibbins, S E. Hopwood, R Jones , M C. Parkin, and M Lauritzen (2002), Stroke , 33, 2738-2743.

6     Supramolecular Chemistry And Self-assembly Special Feature: Cooperative anion binding and electrochemical sensing by modular podands Lagili O. Abouderbala, Warwick J. Belcher, Martyn G. Boutelle, Peter J. Cragg, Jonathan W. Steed, David R. Turner, and Karl J. Wallace Proceedings National Academy of Science 2002 99: 5001-5006

Dr. Martyn G. Boutelle

Dept. of Bioengineering

Bagrit Centre

Imperial College London

South Kensington Campus

London SW7 2AZ

Tel: +44 (0)20 7594 5179

m.boutelle@imperial.ac.uk