In their lab at Stanford, Sebastian Osterfeld and Heng Yu are spying on some of the smallest markers for cancer in the human body. But instead of using microscopes, they're using magnets.
"It's actually a very convenient way of accomplishing that. Names getting a biological signal and converting it to an electronic signal," said Osterfeld.
Their device uses a specially designed chip which holds a blood sample. On that chip are sensors with so-called "capture antibodies" to attract the tiny proteins associated with cancer cells.
But in order to make them visible, the system adds a second set of antibodies. They're designed to latch onto both the trapped protein molecules and tiny flecks of a specially coated metal, dubbed nano-tags, which are also added to the mix.
"So the nano particles make the biological molecules visible to us because we can detect the nano particles," said Osterfeld
To do that, they insert the chip into a reader equipped with magnetic sensors -- the more metallic nano-tags there are, the higher the reading. That lets researchers know if the proteins from cancer cells are present and in what concentration.
"So theoretically we can detect multiple markers for multiple cancers no problem," said Yu.
Older systems currently use optical readers to spot the same chemical reactions. But the Stanford team believes their magnetic unit is several hundred times more sensitive.
"It can find cancer in early stage, it can detect different types of cancers and can be used to monitor the treatment of cancer patients," said Yu.
And scientists hope earlier treatment will translate to much greater survival rates.
The goal is to scale the unit down to a handheld device. It also promises to be much less expensive than optical systems which can run into the tens of thousands of dollars.