Rapid Virus Detection Breakthrough: Primer-Independent Linear Rolling Circle Amplification

Strategic Insights -

Researchers from Fudan University in Shanghai, China, have developed a novel system for rapid virus detection using primer-independent linear rolling circle amplification combined with DNA-templated silver nanoclusters. This breakthrough has far-reaching implications for the detection and prevention of viral infections, particularly in high-risk areas such as Asia.

Key Takeaways:

  • The new system, developed by Jingpu Zhang and colleagues, uses a primer-independent linear rolling circle amplification (LRCA) method that eliminates the need for traditional qPCR-based methods.
  • The system utilizes DNA-templated silver nanoclusters (AgNCs/DNA) as signaling probes, which amplify fluorescence signals through the G-proximity enhancement effect.
  • The approach offers rapid signal amplification, precise single-base mismatch discrimination, and a broad linear range of detection, making it suitable for various DNA detections.
  • The system requires only 1 mL sample and costs 40 min at 25-30 °C, making it adaptable for point-of-care tests.
  • Successful applications have been demonstrated in urine samples for E gene in RNA virus (SARS-CoV-2) and VP2/3 gene in DNA virus (BK human polyomavirus, BKV).
  • The modular design of padlock probes (PlPs) and universal signal probes allows for near-room temperature reaction conditions, small sample requirements, and rapid reaction.

Statistics:

  • Detection limits: 10^-10 mM for E gene in RNA virus (SARS-CoV-2) and 10^-1 mM for VP2/3 gene in DNA virus (BK human polyomavirus, BKV)
  • Reaction time: 40 min at 25-30 °C
  • Sample volume: 1 mL
  • Sensitivity and specificity: 95.6% and 91.1% respectively, in detecting HHV-6 DNA from urine samples
  • Computational cost: reduced, as the system does not require complex computational analysis

Sources:

  • Zhang, J., Dai, F., Shi, Y., et al. (2025). Rapid virus detection by primer-independent linear rolling circle amplification combined with DNA-templated silver nanoclusters. Analytica Chimica Acta, 1377, 344646.
  • NewsRx. Recent Findings in Polyomavirus Described by Researchers from Fudan University (Rapid virus detection by primer-independent linear rolling circle amplification combined with DNA-templated silver nanoclusters). Medical Letter on the CDC & FDA. November 2, 2025; p 670.
  • Elsevier. Analytica Chimica Acta. (www.journals.elsevier.com/analytica-chimica-acta/)
  • Fudan University. Department of Basic Research, Shanghai Public Health Clinical Center. (2901 Caolang Highway, Shanghai, 201508, People's Republic of China)