生態環境評価を目指す迅速簡便な環境由来DNAセンシング技術

抄録

This study focuses on the development and application of a cell collecting method and an electrochemical sensing system capable of feasibly detecting cell-derived environmental DNA (eDNA) from aquatic environments without the need for labeling or external indicator reagents. Conventional eDNA analysis typically involves collecting water samples and transporting them to a laboratory, where they are analyzed using advanced instruments such as next-generation sequencers (NGS). However, this process requires specialized expertise and equipment, making it unsuitable for rapid, on-site environmental monitoring. To address this limitation, we aimed to establish a novel sensing platform that enables efficient eDNA detection directly in the field. As model environmental samples, we prepared suspensions of cells in phosphate-buffered saline (PBS) and natural river water. We then developed a new method for cell collection and DNA amplification, along with a detection technique based on sequence complementarity that does not require DNA labeling. For cell recovery, we employed a combination of multiple filters, which allowed us to complete the entire pretreatment process in approximately 10 minutes. For detection, we utilized a sensor array incorporating synthetic nucleic acid probes with ferrocene moieties at their termini. This system successfully detected DNA in river water at environmentally relevant concentrations (38 cells/mL), demonstrating both high sensitivity and specificity. The integration of these technologies enables a streamlined workflow from sample collection to detection, without the need for complex laboratory procedures. These results suggest that our approach significantly enhances the feasibility of rapid, on-site eDNA monitoring, offering a promising tool for real-time environmental assessment and biodiversity studies in various aquatic ecosystems.