INU Scientists Develop New “TwinDemic” Diagnostic System for Rapid Viral Testing

A novel viral detection tool offers simultaneous and rapid detection of SARS-CoV-2 and influenza A virus

Diagnosing simultaneous infections of multiple respiratory viruses is challenging. Researchers from Korea have now addressed this issue by developing a TwinDemic Detection (TDD) system, a point-of-care diagnostic tool that leverages a novel, non-enzymatic signal amplification method. By testing its performance using human nasopharyngeal samples, TDD was shown to detect SARS-CoV-2 and influenza A virus simultaneously, highlighting its potential application in rapid on-site testing for a wider range of viruses.

Image title: Schematic illustrations of the TDD system, the microfluidic chip, fluorescence generation, and clinical testing.

Image caption: Simultaneous infections by multiple respiratory viruses are challenging to diagnose. Against this backdrop, scientists from Incheon National University have now developed a rapid, accurate, and sensitive point-of-care assay for detecting SARS-CoV-2 and influenza A virus simultaneously, aiding in limiting viral transmissions.

Image credits: Prof. Eunjung Kim from INU, Korea.

Image source link: https://doi.org/10.1016/j.snb.2024.136933

License type: CC BY-NC-ND 4.0

Usage restrictions: Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted.

The COVID-19 outbreak in 2019 triggered measures to raise public awareness regarding pandemics and also led to fast-tracked vaccine development. While these measures helped reduce viral transmission significantly, it also had some unintended consequences, such as an overall reduction in the spread of other viruses, leading to pauses in vaccination regimes. However, fast-mutating pathogens like viruses still pose a significant threat, with predictions of co-infections with multiple viruses causing “twindemics” or “tripledemics” in the future!

Reverse Transcriptase-quantitative PCRs (RT-qPCRs) are reliable disease diagnostic assays but are constrained by the use of expensive equipment and reagents, limiting their utility in resource-constrained settings. Therefore, a rapid, accurate, and sensitive molecular diagnostic tool is warranted for the simultaneous detection of multiple viruses at the point-of-care.

To address this gap, a team of scientists from the Republic of Korea, led by Professor Eunjung Kim from Incheon National University (INU), recently developed a novel TwinDemic Detection (TDD) system, designed for simultaneous detection of SARS-CoV and influenza A virus (IAV). Their findings, published in the prestigious Sensors and Actuators B: Chemical journal, was made available online on 13 November 2024 and will be published in volume 424 of the journal on 1 February 2025.

“The TDD includes a transparent poly (methyl methacrylate) microfluidic chip with hydrogel-based, enzyme-free gene detection sensors, along with a handheld fluorescence reader,” explains Prof. Kim as she describes the detection system. The hydrogel chambers are embedded with customized probes to detect the two target viral pathogens: SARS-CoV-2 (CoV) and IAV. The reaction between the target viral DNA and the specific probe system amplifies the fluorescence signal.

Notably, the TDD system is easy to use, cost-effective, and has a detection limit of 0.46 picomolar (pM) for CoV and 0.39 pM for IAV. To confirm TDD’s diagnostic efficiency, 15 nasopharyngeal swabs each from healthy individuals, patients with COVID-19, and those with Flu A were tested. For COVID-19 diagnosis, the TDD system correctly predicted positive samples in 93.3% of the cases, and negative samples in 96.7% of the cases. For IAV, positive and negative samples were correctly predicted in 100% and 96.7% of the cases, respectively.

Elaborating on the prospects of the TDD system against the team’s findings, Prof. Kim adds, “The application of our TDD system can be further expanded by introducing additional channels and sensing hydrogels on the microfluidic chip, as well as integrating highly sensitive nucleic acid amplification systems for simultaneous detection and differentiation of a wider range of viruses.”

Overall, this study presents and highlights the TDD system as a novel point-of-care diagnostic tool that enables an accurate and rapid on-site detection of multiple viruses simultaneously and could aid clinicians make timely and appropriate treatment decisions.

Reference

*Corresponding authors’ emails: issac@yuhs.ac (Dr. Seung Jae Oh); e.kim@inu.ac.kr (Prof. Eunjung Kim); eklim1112@kribb.re.kr (Dr. Eun-Kyung Lim)

About Incheon National University

Incheon National University (INU) is a comprehensive, student-focused university. It was founded in 1979 and given university status in 1988. One of the largest universities in South Korea, it houses nearly 14,000 students and 500 faculty members. In 2010, INU merged with Incheon City College to expand capacity and open more curricula. With its commitment to academic excellence and an unrelenting devotion to innovative research, INU offers its students real-world internship experiences. INU not only focuses on studying and learning but also strives to provide a supportive environment for students to follow their passion, grow, and, as their slogan says, be INspired.

Website: http://www.inu.ac.kr/mbshome/mbs/inuengl/index.html

About the author 

Professor Eunjung Kim received her Ph.D. in Chemical and Biomolecular Engineering from Yonsei University in 2014 and worked as a Research Associate at Imperial College London (2014-2019). She later joined Incheon National University as Assistant Professor in the Division of Bioengineering. Her research focuses on developing advanced biosensing platforms using functionalized nanomaterials to detect disease biomarkers with exceptional sensitivity and specificity. By integrating materials science and nanoparticle technology, the Kim Research Group leads the advancement of next-generation healthcare technologies through interdisciplinary research that bridges fundamental science with clinical needs in biomedical applications, including biosensing, drug/gene delivery, and diagnostics.