• Developing and applying single molecule localisation microscopy techniques for the elucidation of chromatin architectur, and cellular ultrastructure in particular cytoskeletal changes in response to disease, as well as correlative SMLM-EM of mitochondria.
• Discovering the fundamental photophysical properties of new materials at the single molecule level with a special focus on the characterisation of substituted amino naphthalene diimides.
• Understanding how energy is transported around in multi-chromophoric dye molecules, polymer chains, and nanoparticles
• Using SM techniques to address biophysical problems such as protein folding, aggregation, and conformational change.

“Home-built” Super-Resolution Microscopes

The Bell Lab in the School of Chemistry at Monash University houses two wide-field super-resolution imaging setups. These modular “home-built” systems are assembled around Olympus inverted fluorescence microscope frames, equipped with multiple laser diodes (405 nm, 488 nm, 532 nm, 561 nm, 647 nm), a pair of Andor iXon EM-CCDs aligned for dual-colour imaging and a pco sCMOS detector for higher frame-rate acquisition. 

Super-Resolution Cellular Imaging Techniques

Direct Stochastic Optical Reconstruction Microscopy (dSTORM)

To image fixed cells, we use single molecule localization microscopy (SMLM) 

Expansion Microscopy (ExM)

First published in 2015, ExM has dramatically revised the way microscopists enhance imaging resolution. Instead of 

Super-Resolution Optical Fluctuation Imaging (SOFI)

Biological Investigations

Viral proteins remodelling subcellular structures

Visualizing DNA-damage responses

Correlative celluar imaging (AFM - dSTORM - SEM)

Atomic Force Microscopy (AFM, image above) and Electron Microscopy (EM) gives a more holistic image, showing the entire environment of the target location which pairs well with dSTORM’s specific structure labelling. When these techniques are combined they can reveal the target structure along with the environment it’s in. Using the Soft Materials and Colloids (SMaC) Lab’s AFM at Monash University (http://users.monash.edu.au/~richardt/) the Bell group is working on imaging internal cellular structures on both AFM and dSTORM, opening up a wide range of investigations of various cellular perturbation states, including drug induced microtubule polymerisation/depolymerisation.

Super-Resolution Fluorescence Imaging

In addition to single molecule fluorescence, the Bell wide field fluorescence setups are capable of performing super-resolution fluorescence imaging. This new field of fluorescence imaging enables the imaging of samples at sub-diffraction levels, with resolutions greater than 30nm being obtained, representing a greater than 10 fold increase in resolution over standard epifluorescence measurements. The Bell group has primarily focussed on performing dSTORM and SOFI measurements previously, but expansion microscopy, PALM, and PAINT imaging are all possible on the setups.

Ultrafast Time-Resolved Imaging

In addition to the wide field microscopes, the Bell lab is also home to a custom built confocal microscope with two APD detectors capable of detecting fluorescence on a nanosecond or lower timeframe. This ultrafast detection gives the Bell lab the capacity to perform high complexity analyses of fluorescent species including FCS, FLCS, TCSPC, FLIM, FRAP, and FDAP. Combined with the group’s conventional UV-visible and fluorescence spectrometers, this allows complete optical analysis of novel fluorophores from absorption to fluorescent lifetimes.