01 May 2012
Conference and mini-exhibition highlight medical and life science applications of photonics.
By Matthew Peach, at Imperial College, LondonPhotonex conference and exhibition has extended the event’s brand to a “roadshow” with a one-day conference and mini-exhibition taking place at the end of April at Imperial College, London.
Two parallel conferences addressed respectively Advances in photonic tools and techniques for the life sciences and tutorials on photonics techniques and instrumentation. The former were generally highly academic presentations while the latter were extended product and application descriptions by some of the roadshow’s main exhibitors.
Xmark Media and Photonex event director Laurence Devereux told optics.org, “Significant advances in the development of optical techniques are leading to an increasing role of photonics in the study of various problems in the life sciences, in medicine, clinical sciences, and neurophysiology.
"Researchers are looking for better ways to analyse complex processes and photonics underpins many of the most promising approaches for medical diagnosis, drug development and other clinical applications.”
Topics presented during the day-long academic track included:
Super-resolution and single-molecule FRET in living bacteria. Dr Achillefs Kapanidis (Biological Physics, University of Oxford) discussed super-resolution imaging approaches for studying the sub-cellular localization, mobility and abundance of polymerases in bacteria, as well as methods for internalizing fluorescent biomolecules for long-term tracking and single-molecule FRET in living cells.
Fluorescence lifetime tomography: mesoscopic and macroscopic 3-D imaging. James McGinty (Photonics Group, Physics, Imperial College London) spoke on optical projection tomography and diffuse fluorescence tomography as techniques for mesoscopic and macroscopic 3-D imaging. Their extension to 3-D fluorescence lifetime imaging was described and McGinty gave examples of in vivo imaging.
Intra-vital Imaging of SRC Response to Dasatinib Treatment using FLIM-FRET. Prof. Kurt Anderson (Beatson Institute for Cancer Research, Glasgow) explained how intra-vital Fluorescence Lifetime IMaging - Fluorescence Resonance Energy Transfer is used to study the effects of microenvironment on cell migration, and monitor drug response both at the sub-cellular level and with respect to features of the tissue and a tumor.
She told the conference, “One of the most utilised multiphoton [nonlinear] microscopy techniques is two-photon fluorescence, in which the biomolecules of interest are labelled with fluorophores, which are optically excited via simultaneous absorption of two photons.”
Optical coherence tomography imaging of native tissue. Dr Steve Matcher (Kroto Research Institute, University of Sheffield, pictured below) described how polarization-sensitive optical coherence tomography (PS-OCT) is used to rapidly map the 3-D organization of collagen fibres in ex-vivo cartilage. Structural images are used to quantify wound healing rates in tissue engineered wound models.
Matcher concluded, “PS-OCT shows potential as a tool to rapidly and quantitatively map the 3-D spatial orientation of collagen fibers in native and diseased cartilage. Structural OCT is able to track the formation of neoepidermis on DED scaffolds by a fibroblast/keratinocyte co-culture.”
Optical sectioning via structured illumination and structured detection was presented by Prof Tony Wilson (Engineering Science, Optical Microscopy Group, University of Oxford).
Towards developing a terahertz metrology in applying time-domain spectrometry serving the Life-Sciences’ Grand Challenges. Dr Robert Donnan (Electronic Engineering, Queen Mary, University of London) presented a review of current “grand challenges” in biological and chemical sciences and of the relation of terahertz Time Domain Spectrometry to them.
Monitoring fast neuronal signaling in 3D with an acousto-Optic Lens 2-photon microscope. Professor Angus Silver (Neuroscience, Physiology and Pharmacology, University College London) described how two-photon microscopy is widely used to study brain function at the synaptic, neuronal and network level.
He commented,“Present designs are limited in their temporal resolution and because microscopes are typically designed to image in a single plane. This is problematic for studying neural signaling which occurs on the 1-100ms timescale and is distributed in 3D space.”
Silver described a 3D 2-photon microscope based on a novel acousto-optic lens design that overcomes these limitations, including the design details of the AOL microscope and demonstration of its utility by measuring fast neuronal signaling in 3D, both in vitro and in vivo. “We use fluorescent neuronal tracers and calcium indicators to measure AP-evoked [Ca2+] transients in spines, dendritic shafts and somata of neurons from mouse sensory cortex,” he said.
Observation of individual muscarinic receptors in cultured cells and cardiac tissue slices by TIRFM was presented by Dr Justin E. Molloy (Physical Biochemistry, MRC National Institute for Medical Research, London).
Elson described recent developments and concluded, “This technology has been assessed in vitro and results suggest that it could be used to align and register pre-operative medical images onto the live endoscopic view for surgical guidance.
Exhibition and new products
Some key exhibitors’ new products were demonstrated at Photonex London, including:
Andor’s ultra-sensitive iXon EMCCD camera is designed for hyperspectral imaging and “may lead to new generation of rapid, automated cancer screening systems,” claims the company. Applications could be in the detection of malignant melanomas, the most dangerous type of skin cancer, which is caused mainly by intense episodes of UV exposure.
Toptica Photonics’ FemtoFiber smart family of ultrafast fiber lasers offer dedicated solutions for different applications. For example, the FemtoFErb 1560 is suitable for terahertz generation with InGaAs antennae; while the FemtoFErb 780 is suited for non-linear microscopy or microlithography.
e2v Technologies’ ultra fast linescan camera uses the new CXP interface. The company’s ELiiXA+ linescan camera uses multiline CMOS technology to process 100,000 lines/s in a 16-kpixel format. High response combined with low noise level enables high signal-to-noise ratio when short integration times are required.
NKT Photonics’ SuperK Extreme supercontinuum laser sources are high power, ultra-broadband white light sources that provide a comprehensive choice of output power, repetition rate and ultra bright output over the 400-2400nm wavelength range. Applications include: Confocal microscopy, fluorescence lifetime imaging (FLIM), spectroscopy, optical tomography, and semiconductor inspection.
About the Author
Matthew Peach is a Contributing Editor to Optics.org