Researchers at the Karolinska Institute have devised an innovative approach utilizing DNA nanoballs for the detection of pathogens, with the aim of streamlining nucleic acid testing and revolutionizing pathogen identification. Their findings, recently published in Science Advances, open the door to a straightforward electronic-based testing method capable of rapidly and affordably identifying various nucleic acids in diverse scenarios.
Principal investigator Vicent Pelechano, an associate professor in Karolinska Institute’s Department of Microbiology, Tumor, and Cell Biology, is cautiously optimistic about the technology’s potential to detect a wide range of pathogenic agents in real-world applications.
“The methodology involves merging Molecular Biology, specifically DNA nanoball generation, with electronics, employing electric impedance-based quantification to create an innovative detection tool,” explains Vicent Pelechano.
The researchers adapted an isothermal DNA amplification technique known as LAMP to generate tiny DNA nanoballs measuring 1-2μM when the pathogen was present in the sample. These nanoballs are then guided through minuscule channels and electrically identified as they pass between two electrodes. The method exhibits exceptional sensitivity, capable of detecting as few as 10 target molecules, and delivers results within an hour using a compact, stationary system.
“Swift and precise detection of genetic material is critical for diagnostics, especially in response to the emergence of novel pathogens,” notes Vicent Pelechano.
During the recent COVID-19 pandemic, protein-based diagnostics gained widespread use for rapid testing. However, these methods necessitate the time-consuming development of high-quality antibodies. In contrast, nucleic acid-based approaches offer greater development ease, heightened sensitivity, and inherent flexibility, as highlighted by the researchers.
This new label-free detection method has the potential to expedite the deployment of new diagnostic kits. By integrating cost-effective mass-produced electronics with lyophilized reagents, this technology holds promise for delivering an affordable, widely accessible, and scalable point-of-care device.
The research team embarked on this endeavor as an extension of their prior work in LAMP-based SARS-CoV-2 detection during the pandemic. Currently, they are actively exploring applications to incorporate this technology into fields such as environmental monitoring, food safety, and the detection of viruses and antimicrobial resistance. Additionally, the team is considering options for licensing or potentially establishing a startup to leverage this technology, as they have recently filed a patent application for it.
More information:
Muhammad Tayyab et al, Digital assay for rapid electronic quantification of clinical pathogens using DNA nanoballs, Science Advances (2023). DOI: 10.1126/sciadv.adi4997
Source: Karolinska Institutet