Miniscule sensors could help test for damage to cells

The sensors – so small that several fit into a single cell – measure the tiny electronic signals that keep cells functioning.

When signals become irregular, they could indicate that cells have been damaged by inflammation, toxicity, or disease.

Experts believe their sensors could help create tests to diagnose and monitor the progress of conditions such as macular degeneration, Parkinson’s and Alzheimer’s diseases.

They may also boost drug development by offering insights into how cells respond to therapy.

The project, which has been on the go for three years, is being led by Dr Colin Campbell of the University of Edinburgh’s school of chemistry.

He said: “Electronic activity in cells is strictly controlled and normally runs like clockwork – so when it goes wrong, it can be a sign of disease. Our device offers a safe, effective method to test the health of cells.”

The sensor is made of molecules, known as “reporter” molecules, which are capable of responding to cell electrical activity, or “potential”. They have been mounted on to gold particles that can be inserted harmlessly into cells.

The result is a sensor which can be scanned with a laser to give a measure of electrical activity in the cell, indicating whether it is healthy or not.

Dr Campbell said: “What you’ve got is effectively a nanosensor. The particles are about 130 nanometres in diameter. They’re absolutely tiny.

“The reporter molecule changes its structure depending on the potential inside the cell.”

The findings were published in the American Chemical Society journal Nano.

Dr Campbell added: “We’re looking to translate it out of chemistry labs and get it more into biology labs, so that it becomes a standard tool of biology. We would also like to look at using it ‘in vivo’, say in a hospital situation.”