Determination of paralytic shellfish toxins in dinoflagellateAlexandrium tamarense by using isotachophoresis/capillary electrophoresis

Abstract

Baseline separation of seven paralytic shellfish toxins (PSTs), namely decarbamoylsaxitoxin (dcSTX), saxitoxin (STX), neosaxitoxin (NEO), gonyautoxin-2 (GTX-2), gonyautoxin-3 (GTX-3), gonyautoxin-1 (GTX-1), and gonyautoxin-4 (GTX-4), was achieved by using capillary ITP (CITP)/CE with UV detection. Separation parameters including duration time and voltage in CITP process, separation voltage, and pH and concentration of buffer were optimized. The developed method provided linear responses from 1.3 to 200 microM for the PSTs. The LOD ranged from 0.1 to 0.3 microM. PST extracts from two algal strains of Alexandrium tamarense were analyzed and the toxin concentrations in the samples were quantified with an internal standard method by using NEO as the internal standard. The algal extract of A. tamarense HK9301 contained 332 microM GTX-2 and 224 microM GTX-3, while the PSTs were not detected in the extract of A. tamarense CI01.

Capillary isotachophoresis from the student point of view – images and the reality

“…The state of ITP in many fields was reviewed by many authors [97 -118] [190,191] Natural neurotoxins [192,193] Aromatic and aliphatic sulfonates [194,195] Pharmaceuticals [85, 86, 196 -205] Coupling of ITP with NMR [190,192,196,[232][233][234][235][236][237] [260] Gebauer and Bocek [119] was published in 2002. From this date, over a hundred novel applications and methods were published; a short survey of these works is given in Table 2.…”

Enhanced sensitivity and resolution for the analysis of paralytic shellfish poisoning toxins in water using capillary electrophoresis with amperometric detection and field‐amplified sample injection

“…As a result of the substitution in guanidium moieties by different groups, PSTs show a variety of p K a values: 8.22 and 11.28 for STX , 8.10 and 10.84 for dcSTX, 6.75 for GTX1,4 and 8.65 for neoSTX . As pH increased, the charge states of PSTs are changed from positive to nearly neutral or negative due to the presence of guanidine, carbamoyl, hydroxyl, or sulfate groups on the structures.…”

“…CE has emerged as an established separation technique for the assay of structurally similar compounds, owing to its recognized merits relative to HPLC in terms of high resolution, simplicity, small sample, and solvent consumption . CE‐UV method has been applied for the analysis of PSTs at ppm level in algae and shellfish . The detection limits for PSTs have been improved to be 16–30 nmol/L by combining the capillary ITP mode with CZE‐MS .…”

Detection of microbial food contaminants and their products by capillary electromigration techniques

“…Quantitative aspects of the application of CITP-CE to the analysis of a wider set of PSP toxins have been addressed in a recent paper by Wu et al [118]. The effect of five experimental conditions …”