Cyclodextrins as capture agents of lipophilic marine toxins

Seafood contamination with marine toxins due to harmful algal blooms (HAB’s) is a global public health issue on the rise. Most Countries have monitoring programs for the detection of toxins in shellfish of toxic phytoplankton in seawater to prevent consumer intoxifications. The use of solid phase adsorbent and toxin tracking (SPATT) technology as toxin detection straight from the aquatic environment could complement the labour-intensive traditional monitoring methods. In this work, several types of cyclodextrins (cyclic oligomers with a conical structure and an internal cavity) have been evaluated as novel materials for SPATT. Cyclodextrins were tested at Masnou harbour (Catalonia, NW Mediterranean) during a Dinophysis sp. bloom. The cyclodextrins and the commercial Diaion (HP-20) were deployed twice for a 1-week period at five different locations of Masnou harbour. At the time of the experiment, Dinophysis sp. reached abundances as high as 91 341 cells /L.

Successful accumulations of the lipophilic marine toxins; okadaic acid (OA) and pectenotoxin-2 (PTX2) were quantified by Liquid Chromatography- tandem Mass Spectrometry (LC-MS/MS).

Higher levels of PTX2 were found in all cyclodextrins whereas OA and PTX2 contents were similar in the commercial resin. Accumulation of OA was higher in the commercial resin than in cyclodextrins, but these proved best for PTX2 adsorption. A clear correlation between cell abundance and toxin accumulation was observed.

The research has received funding from the Ministerio de Ciencia, Innovación y Universidades (MICINN), the Agencia Estatal de Investigación (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER) through the CIGUASENSING project (BIO2017-87946-C2-1-R and BIO2017-87946-C2-2-R). The authors acknowledge support from CERCA Programme/Generalitat de Catalunya.