Establishment of a detection method for Prorocentrum minimum by nuclease protection-based nucleic acid chromatography...

A detection method, named as nuclease protection-nucleic acid chromatography strip assay (NP-NACSA), was established to detect Prorocentrum minimum, a common harmful algal blooms-forming algal species. In this study, the developed NP-NACSA requires no nucleic acid amplification, but directly targets rRNA obtained from broken cells. After converting the target rRNA to DNA by nuclease protection, the resultant DNA is automatically analyzed by nucleic acid chromatography strip. The specificity, anti-interference ability and sensitivity of the established NP-NACSA were evaluated, respectively. The specificity test showed that NP-NACSA had good detection specificity, producing positive results only for the target algae and no cross-reaction with all control algal species. NP-NACSA has good anti-interference ability and its detection performance was not affected by the interfering algal species. The sensitivity test showed that the detection limit of NP-NACSA for RNA was 1.28 ng. The cellular detection limit of NP-NACSA for simulated natural water samples was 3.25 × 10³ cells mL^-1, which is lower than the density of HABs triggered by P. minimum (1 × 10⁵ cells mL^-1). Overall, the developed NP-NACSA is independent of special equipment, requires no nucleic acid amplification process, and can accomplish the specific, convenient, and intuitive detection of P. minimum.