CSIRO patents new microscopy method

CSIRO has patented an improved microscopy method for measuring the shapes and sizes of proteins, which could lead to more targeted pharmaceutical products.

Called Differential Aberration Correction (DAC) microscopy, the method uses conventional fluorescence microscopy to measure distances at the molecular level in two and three dimensions.

The method allows scientists to measure proteins in solution, instead of using coated or crystallised proteins as do other techniques.

The leader of CSIRO’s Biotech Imaging team, Dr Pascal Vallotton, said DAC microscopy measures distances in nanometres and could be used to accurately measure the dimensions of membrane receptors, a class of biomolecules targeted by over 50% of pharmaceuticals.

“Understanding the complex structures of these molecules and how new drugs affect their structure will help drug companies design more effective pharmaceuticals,” Vallotton said.

The technique uses a software-based approach to precisely correct light distortion at every point in the image. It is an improvement on an older technology, called FRET, which can measure distances from 1–10 nanometres. DAC can measure 1–250 nanometres, providing a more complete picture.

“We are currently looking at more samples that require the ability to see single molecules with very high contrast. Results are extremely encouraging and we are starting to explore commercial possibilities,” Vallotton said.

The DAC software was recently demonstrated in the US and will be presented at the Society for Biomolecular Sciences Conference, held in Lilles, France, from 26 to 30 April 2009.