Rapid identification of microorganisms using optical spectroscopy

1. Selected current programs Rapid identification of microorganisms using optical spectroscopy Optical sensing of trace pathogens using Surface Plasmon Resonance Rare Earth Doped Nanocrystals:Novel Fluorescent Tags for Bioimaging • Sensitivity increase of a Surface Plasmon Resonance (SPR) sensor through surface enhancement of SPR and nanoscale “fractal” surface profiling. • Customisation of the sensor surface for the detection of selected biotoxins, using the method of reporter conformational changes and using appropriate active bio-surfaces. • Fluorescence probes that are superior to both dyes and quantum dots • Resilience to photobleaching for improved imaging • Multiple emission lines for multiplexing • Long relaxation time to discriminate against autofluorescence in time-resolved imaging. • Synthesis of nanocrystals based on II-VI, III-V and other oxides doped with selected rare earth ions, customized for the use as fluorescent probes • Surface modification to ensure water solubility, and derivatised to ensure further connectivity • Nanocrystals linked with custom-derived oligonucleotide probes and antibodies and introduced into cells • Spectroscopic characterisation of yeast strains and lactic acid bacteria, distinction from other microorganisms or somatic cells, variations with life cycle. • Aim: to build instrumentation for rapid monitoring of industrial processes. • Foundation for simple optical essays relevant for industrial applications of yeast and bacterial population in milk and its products. Hemant Bhatta, Robert Learmonth, Alex Stanco (Lastek Pty Ltd. Hongfei Dou, Dairy Australia (?), MQ Anne Barnett,Danny Wong, Danny Alam, Nem Jovanovich.MURDG, MQ Krystyna Tomsia, Uwe Happek (UGA) , Yiping Zhao (UGA), Juergen Wiegel (UGA) , Jacek Gaertig (UGA), Peter Bergquist, Andrew Try, (NIH?), US Congress Ewa M. Goldys

3. Research priorities Development of sensitive probes for cellular imaging Imaging of small molecules • Development of new technologies to enable higher sensitivity biological imaging in living cells • Requires creation of fundamentally new probes with enhanced spectral characteristics • Goal of improving detection schemes by a factor of 10 to 100. • Parallel improvements in probe targeting, cellular delivery, and signal detection will be needed. • The ultimate goal will be to develop probes that can be used to routinely achieve single molecule sensitivity for imaging dynamic processes in living cells. • The research programs of relevance to these aims may emphasise pre-clinical development of imaging agents for the detection, and diagnosis, or measurement of treatment efficacy for different disease processes. • Small molecules are extremely important to functions of the cell at the molecular level. Most medicines, from aspirin to antihistamines, are small molecule compounds. • Development of high-specificity/high-sensitivity probes with the goal of improving detection sensitivity 10- to 100-fold. • Research efforts towards specificities, activities and applications of imaging probes for a wide range of diseases and biological functions. • The development of these probes will be aided by discoveries that emerge from the screening of small molecules for their affinity for targets of interest. Ewa M. Goldys