9360219 Powell Novel probes are proposed for the study of cytoskeletal structures and processes by electron microscopy. These will comprise large cluster complexes of gold, platinum and palladium 0.8 nm - 2.4 nm in diameter covalently lined to phalloidin, cytochalasin B, colchicin and taxol via a single reactive functional group incorporated into their ligand spheres. The proposed conjugates will penetrate 20-30 u or more into cell sections and achieve significantly higher resolution than colloidal gold=antibody conjugates. They will be microinjectable and compatible with living cells, and will be used to extend the use of electron microscopy to the study of organisms such as procaryotic bacteria, in which antibody probes are not feasible. Combined labels including both a gold cluster and a fluorescent moiety will be used to prepare additional probes with the same molecules, enabling correlation of fluorescence confocal microscopy and electron microscopy data from a single labeling experiment. The preparation of molecular wires will be attempted by the in vitro assembly of gold-labeled cytoskeletal components, followed by silver enhancement. %%% A new class of probes for cystoskeletal structures and processes, compatible with living cells, will permit electron microscopy with higher resolution than antibody probes. In vitro assembly of labeled cytoskeletal components will be used to prepare novel conductive molecular wires, and may be applied to the fabrication of other molecular devices, catalysts, new materials and novel molecular detection systems. ***
