Enhanced sensitivity in PCSK9 detection using binding-induced DNA walker-triggered Argonaute protein-based DNA circuit.

Detecting PCSK9 (Proprotein Convertase Subtilisin/Kexin Type 9) levels is important for assessing lipid metabolism and cardiovascular disease risk, as well as for optimizing treatment plans. Traditional methods such as ELISA and western blotting, while sensitive, are time-consuming and require skilled personnel. Recent advancements in biosensors offer quicker, more sensitive, and cost-effective alternatives, though they face challenges such as complexity and scalability. In this study, we developed a novel sensing method based on a binding-induced DNA walker-triggered TtAgo-based DNA circuit for highly sensitive detection of PCSK9. This method combines the specific recognition ability of the binding-induced DNA walker and the high sensitivity of the TtAgo-based DNA circuit, allowing for precise detection of PCSK9. Our method demonstrated a limit of detection as low as 2.5 fg/mL, significantly outperforming other techniques. Furthermore, the method showed excellent specificity and stability, retaining 93.1% of its initial signal after 15 days. This method allowed accurate detection of PCSK9 in serum samples. These results indicate that the method is a promising tool for PCSK9 detection in clinical settings.