2013 Joule Medal and Prize

Professor Paul French, Imperial College London. For his contributions to the development of Fluorescence Lifetime Imaging (FLIM) and its wide deployment from underpinning laboratory research to clinical application

Natural fluorophores or synthetic fluorescent dyes can be sensitive probes of local environmental change, chemical reaction or resonant energy transfer processes. Consequently, Fluorescence Lifetime Imaging (FLIM), a multidimensional fluorescence imaging technique that involves determining the average fluorescence decay time for each pixel in a field of view and producing a map of this lifetime data, is currently being developed as a versatile readout of biological function in samples ranging from single cells to bulk tissue. Paul French has applied his extensive experience of ultrafast laser physics and photonics to make vital contributions to all the key components essential to FLIM development. This includes compact and efficient ultrashort-pulse excitation sources, a field where French has an international reputation, initially deploying diode-pumped solid-state lasers but more recently exploiting spectrally versatile fibre-based supercontinuum sources as well as direct diode laser excitation. Key too is ultrafast detection where French has been particularly involved with UK industry in the development and application of time-gated imaging technology. Data acquisition and processing are equally vital areas for which French has led his group to develop crucial software tools. The most remarkable achievement, however, is the diversity of the FLIM instrumentation that French has instigated through numerous national and international collaborations at the frontiers and across the scales of fluorescence imaging. This has ranged from super-resolved FLIM microscopy for cell biology (using stimulated emission depletion) through automated FLIM of sample arrays for high content assays to preclinical imaging of protein interactions in disease models and FLIM of autofluorescence in humans for clinical diagnosis. These advances have helped establish FLIM as a practical and versatile imaging modality and an increasing scientific and commercial success, as indicated by its extensive and growing international deployment.