Cross-disciplinary Interfaces Programme (C-DIP) Fellowship Fund

Lead Research Organisation: University of Bristol
Department Name: Electrical and Electronic Engineering

Abstract

Raman spectroscopy uses laser light to provide an analysis or chemical fingerprint of materials such as human tissue. It has been shown by many research groups that Raman spectroscopy is able to distinguish between cancerous and healthy tissue in the laboratory. Previously, a Raman probe small enough to fit inside a medical endoscope that opens the way for the instant detection of cancers within the oesophagus was developed at Bristol. In the current project, we are investigating the feasibility of adapting the above core technology to make an intelligent hypodermic needle suitable for investigating cancer and cancer like conditions below the skin. The goal is to construct a probe suitable for the study of breast and prostate cancers but shorter probes will also be made for looking at lymph nodes and for tissue identification.The current Raman needle sensor relies on detecting far-field Raman scattering, which is extremely weak. However, to improve Raman scattering process the technology widely known as surface enhanced Raman spectroscopy (SERS) could be used in the new design. SERS exploits the locally enhanced electric field on rough metal surfaces to drastically improve the Raman scattering process. Another, novel, possibility to locally enhance electric fields is to use nano-antenna array as the SERS substrate. Nano-antennas (or optical antennas), currently being investigated by Dr Klemm, are an emerging concept in nanophotonics. Similar to radiowave and microwave antennas, their purpose is to convert the energy of free propagating radiation to localized energy, and vice versa. Optical antennas exploit the unique property of metal nanostructures at optical wavelengths - plasmon resonance. Nanoantennas exhibiting plasmonic resonances can enhance the field leading to SERS signal enhancement that is approximately proportional to the fourth power of the field enhancement factor. This interdisciplinary project brings together research fields of electromagnetics, physics, photonics and nanotechnology. It is very timely and currently unrelated research efforts of Dr Klemm and Dr Day could be combined into a novel research project. Fabricating and testing first proof-of-principle prototypes we want to prove that nano-antennas can indeed improve SERS. This could results in future joint project proposal application.

Planned Impact

not required
 
Description Through the research funded on this grant several discoveries / developments were made:

1. Novel, more efficient nanoantenna device : we have discovered a novel type of the nanoantenna (antenna working at optical frequencies). The new devices is more efficient that the previously known designs, and is able to direct a light in the vertical direction without coupling to plasmons. New nanoantenna might find applications in optical interconnect networks, as well as in new sensing devices.

2. New methods for 3D printing of brain models - this is a part of the project were students were involved. This work was in collaboration with Clinical Research and Imaging Centre, St Michael's Hospital, Bristol. We have developed a methodology and tools for translating MRI images of small children born with brain defects, into 3D models which are used for better diagnosis.
Exploitation Route Based on the finding we're now working on new, large grant bids in order to provide a more focused research effort for the most promising areas.
Sectors Aerospace, Defence and Marine,Electronics,Healthcare
 
Description INRIA Sophia-Antipolis, France 
Organisation The National Institute for Research in Computer Science and Control (INRIA)
Country France 
Sector Public 
PI Contribution I have provided a real-life application cases and measured results for optical nanoantennas and microwave imaging antennas to INRIA Nachos team. I have also introduced a new research field to Nachos group - nanophotonics. INRIA Nachos team has now two members of their staff directly working in this field.
Collaborator Contribution Based on my inputs, INRIA has further developed their numerical simulation tool (based on Discontinues Galerkin method for Maxwell equations). With the improved numerical code, the code was made available to myself and I was able to run complex, real-life problems from the areas of nanophotonics and medical imaging.
Impact We have several joint publications (84893466384 (12, 2013)). The collaboration in multi-disciplinary and involves engineering (Bristol) and applied mathematics (INRIA).
Start Year 2011