Behold The Future...Breakthrough test can diagnose disease on the spot, Paper strip that detects bio-markers could be the next home pregnancy test, applicable to thousands of diseases.
A strip of paper can now sense the presence of virtually any illness — from cancer to the common cold — cheaply and in as few as 30 minutes.
A team of researchers at McMaster University has developed a new diagnostic test that would tell patients in the span of a House episode if they’re suffering from a virus or bacterial infection, or possibly a malignant tumour, all based on a drop of sweat or saliva and a small piece of dried pulp.
The test features a dose of reactive material — the reagent — printed on a strip of litmus-like paper that changes colour to indicate the presence of the DNA sequence for a specific disease.
“Every disease and every infectious agent has genetic material, so in theory this can be used for the detection of any pathogen for any human disease,” said Yingfu Li, a biochemistry professor at McMaster and the Canada research chair in nucleic acids research.
So far in the laboratory, the test has detected genetic sequences for breast cancer cells and Hepatitis C, but could be applied to any disease for which humans have unlocked the genetic code. That includes afflictions from the flu to neurodegenerative diseases to colorectal, prostate and lung cancers, some of the biggest killers in a disease type that’s now the leading cause of death across Canada.
McMaster’s Biointerfaces Institute, which hosts the ongoing study, has been in touch with at least 10 private sector companies and public agencies, Li says. Pro-Lab Diagnostics, an international diagnostics supplier, paid for the project along with two public funding councils, affording the company licensing rights, according to the institute.
The initial target is first-line health professionals in hospitals and doctors’ offices, says co-lead scientist and institute director John Brennan.
“For now, these aren’t meant to be the definitive yes-no; these are meant to be the screen that alerts physicians as to the next course of action,” he said.
For breast cancer, that course could mean more complex, definitive RNA testing, biopsies or mammograms — a battery of tests Brennan wants to pre-empt where possible to reduce public cost and patient inconvenience or harm. Improving the paper test is essential to preventing “false positives,” detection of subset tumours that may never grow enough to be harmful and unnecessary, invasive screening.
One long-term study of mammography from 2014 suggested that the widely used screening technique — about $100 per exam — isn’t reducing the number of women who die from breast cancer.
Clinical testing and a Health Canada thumbs-up await, Brennan hopes. Self-diagnosis courtesy of a store-bought kit — there’s already a prototype, slightly resembling a domino slab — could come only once it’s “as simple as a home pregnancy test.”
The lab uses a standard, industrial-scale inkjet printer to squirt the reactive material onto inexpensive paper strips. That’s part of the test’s appeal to manufacturers wary of pricey specialty devices and aiming to take the innovation “from lab prototype to final product and ultimately to market and sell it,” Brennan said.
He finds the potential benefits in the developing world encouraging as well. Water contamination and disease outbreak might be nipped in the cell bud much earlier with quick, cheap paper tests in clinics or drug stores, he said.
On top of genetic material, molecules such as proteins could potentially be used to indicate specific diseases and disease subtypes, broadening the application of an assessment that puts a new meaning on ink-blot test.
Tracking down toxins such as lead, manganese, uranium and mercury that, in high concentrations, represent “serious threats to human health” is another possible path, Li said.
The McMaster study is slated for publication in February as the cover story in Angewandte Chemie, a peer-reviewed scientific journal based in Germany.