title: Electrochemical RNA genosensors for toxic algal species: enhancing selectivity and sensitivity.
abstract: Harmful algal blooms (HABs) are becoming more frequent as climate changes, with tropical species moving northward. Monitoring programs detecting the presence of toxic algae before they bloom are of paramount importance to protect aquatic ecosystems, aquaculture, human health and local economies. Rapid and reliable species identification methods using molecular barcodes coupled to biosensor detection tools have received increasing attention over the past decade as an alternative to the impractical standard microscopic counting-based techniques. This work reports on a PCR amplification-free electrochemical genosensor for the enhanced selective and sensitive detection of RNA from multiple Mediterranean toxic algal species. For a sandwich hybridization (SHA), we designed longer capture and signal probes for more specific target discrimination against a single base-pair mismatch from closely related species and for reproducible signals. We optimized experimental conditions, viz., minimal probe concentration in the SHA on a screen-printed gold electrode and selected the best electrochemical mediator. Probes from 13 Mediterranean dinoflagellate species were tested under optimized conditions and the format further tested for quantification of RNA from environmental samples. We not only enhanced the selectivity and sensitivity of the state-of-the-art toxic algal genosensors but also increased the repertoire of toxic algal biosensors in the Mediterranean, towards an integral and automatic monitoring system.
authors: Microbia Environnement Observatoire Océanologique, Banyuls/mer, F-66651 France. Electronic address: jahir.orozcoholguin@microbiaenvironnement.eu.
authors: Jahir
authors: J
authors: Orozco
authors: Microbia Environnement Observatoire Océanologique, Banyuls/mer, F-66651 France.
authors: Elisa
authors: E
authors: Villa
authors: Microbia Environnement Observatoire Océanologique, Banyuls/mer, F-66651 France.
authors: Carmem-Lara
authors: CL
authors: Manes
authors: Microbia Environnement Observatoire Océanologique, Banyuls/mer, F-66651 France.
authors: Linda K
authors: LK
authors: Medlin
authors: Microbia Environnement Observatoire Océanologique, Banyuls/mer, F-66651 France.
authors: Delphine
authors: D
authors: Guillebault
mesh_terms: D015374:Biosensing Techniques; D004141:Dinoflagellida / Q000235:genetics*; D055664:Electrochemical Techniques; D004566:Electrodes; D004784:Environmental Monitoring; D006046:Gold / Q000737:chemistry; D057097:Harmful Algal Bloom; D048030:RNA, Algal / Q000032:analysis*; D014873:Water Pollutants
chemical_list: D048030:RNA, Algal; D014873:Water Pollutants; D006046:Gold
keywords: Dinoflagellate; Environmental monitoring; RNA-biosensor; Sandwich hybridization; Toxic algae