Science & Technology, Australia (Commonwealth Union) – A team of biomedical engineers from the University of New South Wales (UNSW) has unveiled a groundbreaking technology: test strips that rival the accuracy of lab-based PCR (Polymerase Chain Reaction) tests while offering swift, on-the-spot disease detection. Published today in Nature Communications, their research suggests broader applications beyond public health.
PCR testing faces challenges such as supply chain constraints, logistical issues, and the need for trained personnel to administer tests and interpret results. Moreover, the emergence of new variants underscores the importance of ongoing research and development to ensure that PCR tests remain effective in detecting evolving strains of the virus. This has opened up the need for more testing options and the need for Research and development to both diagnose and monitor emerging strains.
Lead researcher Professor Ewa Goldys, from UNSW’s Graduate School of Biomedical Engineering, likens the innovation to carrying “PCR in your pocket,” highlighting its potential in biomedical and environmental diagnostics across various sectors such as food industry, agriculture, and biosafety management.
Professor Goldys further indicated that in addition to easily detecting specific gene sequences within samples, unlike PCR, they can conduct tests at room temperature using strips resembling familiar RAT Covid tests – simplifying the process for users.
“So, no more queuing for that PCR test in the future. Also, the cost is very low – currently less than a few dollars per test.”
Dr. Fei Deng, one of the authors of the study, suggests that the newly developed test strips have the potential to accelerate the response to emerging pathogens like mosquito-borne diseases or lumpy skin diseases. They could also pinpoint areas of antibiotic resistance or aid in the search for endangered animal species.
Dr. Deng further indicated that this advancement has the potential to revolutionize infection control in both humans and animals, as well as enhance efforts in quarantine and biodiversity conservation.
“We think we created a new benchmark in biosensing – our gene-based tests will be able to be performed anywhere, any time, by virtually anyone.”
Dr. Yi Li, co-author of the study, explains that in order to elevate the new test strips to PCR standards, the team initially crafted minuscule DNA nano-circles containing a brief sequence corresponding to the target DNA, such as the COVID virus. These nano-circles are incredibly small, measuring only about 2 nanometers, rendering them undetectable by any microscope.
The DNA nano-circles were then combined with the sample under examination along with CRISPR/Cas proteins.
These proteins, celebrated for their association with the Nobel Prize-winning CRISPR/Cas gene editing technology, were specifically programmed by the UNSW team to cleave the DNA of the nano-circles—but only upon activation by DNA from the designated pathogen. “The interaction between a suitably programmed CRISPR/Cas protein and the targeted gene we seek to detect triggers the fragmentation of the DNA nano-circles, causing them to linearize and mimic ‘false targets,’ according to Dr. Li.
This innovative method sets off a molecular cascade reaction.
“We unleash a huge cascade of fake targets which is easy to detect with the testing strips, even if only a few molecules of the original gene target are present.”
The technique was demonstrated using samples of both the COVID-19 virus and helicobacter bacteria, known for causing stomach ulcers.
Professor Goldys notes that the response from the industry to the team’s innovation has been highly favorable.
Professor Goldys further indicated that the implementation of their technology in both industrial and clinical settings within the Australian industry is already underway, with a commitment to maintaining manufacturing operations domestically. They aim to leverage the growing industrial infrastructure to the RNA vaccine production.”
Professor Goldys suggests several potential applications for the new biosensing method. These include its use in biosecurity, where testing strips could identify potential invasive marine species; in environmental science, where DNA testing of samples could indicate the presence or absence of threatened species; and in the detection of cancer cells, a particularly intriguing application. She further mentions that their published study successfully detected cancer mutations in patients’ samples within a clinical setting.
“We hope this will open a path towards universal monitoring of patients undergoing cancer therapies.”
The findings are outlined in the journal Nature Communications and were conducted by researchers associated with UNSW and the Garvan Institute of Medical Research.
