Drug tracked in tissue

 When a new drug is developed, the manufacturer must be able to show that it reaches its intended goal in the body's tissue, and only that goal. Such studies could be made easier with a new method now established at Lund University in Sweden.

The method is a special type of mass spectrometry which can be used on drugs 'off the shelf', i.e. without any radioactive labelling which may change the behaviour of the drug. With this method, researchers György Marko-Varga and Thomas Fehniger have managed to create a molecular image of the drug in the tissue.

The tissue examined comes from biopsies from the lungs of patients with lung cancer and chronic obstructive lung disease (COPD), who have inhaled a drug to dilate the airways. The examination showed the precise spatial distribution of the drug within the tissue. The results are based on an analysis of 3 000 measurement points of 0.01 mm2 in each biopsy sample.

"When you want to register a new drug, you must be able to both explain its exact mechanisms of action and show that it is effective and safe. In order to avoid side-effects, the drug should reach only the cells for which it is intended. Our new technical platform makes it easier to show this", says György Marko-Varga.

He believes it will be possible to use the new technology to develop safer and more effective drug candidates. In the future it could also be used in clinical treatment, to help doctors select the right drug for a specific patient.

The researchers first conducted animal experiments, using drug doses 100 times higher than those now measured in patients. The group then optimised and refined the technology to achieve the sensitivity needed for measuring doses of drugs normally administered to patients.

Professors György Marko-Varga and Thomas Fehniger are both members of the Department of Measurement Technology and Industrial Electrical Engineering in Lund. Thomas Fehniger (who is the principal author of the article) is currently working at The Tallinn University of Technology, sponsored by the Estonian Science Foundation under the European Social Fund, while György Marko-Varga works part time for the University of Tokyo.

The two researchers have previously worked at the pharmaceuticals company AstraZeneca, which has also contributed to the study. The study was recently published in the journal Analytical Chemistry.

More information: A text about the research findings is available at http://pubs.acs.or … 41scene.html and the research article is available at http://pubs.acs.org/doi/abs/10.1021/ac2014349

Provided by Lund University

Quantum sensor tracked in human cells could aid drug discovery

Groundbreaking research has shown a quantum atom has been tracked inside a living human cell and may lead to improvements in the testing and development of new drugs.

Professor Lloyd Hollenberg from the University of Melbourne's School of Physics who led the research said it is the first time a single atom encased in nanodiamond has been used as a sensor to explore the nanoscale environment inside a living human cell.

"It is exciting to see how the atom experiences the biological environment at the nanoscale," he said.

"This research paves the way towards a new class of quantum sensors used for biological research into the development of new drugs and nanomedicine."

The sensor is capable of detecting biological processes at a molecular level, such as the regulation of chemicals in and out of the cell, which is critical in understanding how drugs work.

The paper has been published in the journal Nature Nanotechnology.

Funded by the ARC Centre of Excellence for Quantum Computation and Communication Technology, the research was conducted by a cross-disciplinary team from the University of Melbourne's Physics, Chemistry, and Chemical and Biomolecular Engineering departments.

The researchers developed state of the art technology to control and manipulate the atom in the nanodiamond before inserting it into the human cells in the lab.

Biologist Dr Yan Yan of the University's Department of Chemical and Biomolecular Engineering who works in the field of nanomedicine, said the sensor provides critical information about the movement of the nanodiamonds inside the living cell.

"This is important for the new field of nanomedicine where drug delivery is dependant on the uptake of similar sized nanoparticles into the cell."

Quantum physicist and PhD student Liam McGuinness from the University's School of Physics said that monitoring the atomic sensor in a living cell was a significant achievement.

"Previously, these atomic level quantum measurements could only be achieved under carefully controlled conditions of a physics lab," he said.

It is hoped in the next few years, that following these proof of principle experiments, the researchers will be able to develop the technology and provide a new set of tools for drug discovery and nanomedicine.

Story Source:

The above story is reprinted (with editorial adaptations ) from materials provided by University of Melbourne.

Journal Reference:

L. P. McGuinness, Y. Yan, A. Stacey, D. A. Simpson, L. T. Hall, D. Maclaurin, S. Prawer, P. Mulvaney, J. Wrachtrup, F. Caruso, R. E. Scholten, L. C. L. Hollenberg. Quantum measurement and orientation tracking of fluorescent nanodiamonds inside living cells. Nature Nanotechnology, 2011; DOI: 10.1038/nnano.2011.64