Suitability of the MTT-based cytotoxicity assay to detect okadaic acid contamination of mussels.
The suitability of a cytotoxicity assay based on the MTT colorimetric method has been evaluated for the detection of okadaic acid in mussels. On KB cells, okadaic acid exhibited a dose-dependent cytotoxic effect, the IC50 being inversely related to the exposure time (IC50 = 6.3 ng/ml, 4.0 ng/ml and 1.1 ng/ml after 24, 48 and 72 hr of contact, respectively). Using a contact time of 24 hr, the MTT cytotoxicity assay is suitable for revealing okadaic acid concentrations in mussel samples as low as 50 ng/g of digestive glands, with a sensitivity higher than that of the commercially available kits for enzyme-linked immunosorbent assay (ELISA). In the okadaic acid concentration range from 50 to 1500 ng/g of digestive glands the MTT cytotoxicity assay showed satisfactory accuracy and reproducibility. A high degree of correlation was found between the okadaic acid content of 16 naturally contaminated samples measured by the MTT cytotoxicity assay and by an ELISA.
Tubaro
A
A
Dipartimento di Scienze Biomediche, Università di Trieste, Italy.
Florio
C
C
Luxich
E
E
Vertua
R
R
Della Loggia
R
R
Yasumoto
T
T
D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D003124:Colorimetry; D004396:Coloring Agents / Q000737:chemistry / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007274:Injections, Intraperitoneal; D007624:KB Cells / Q000166:cytology / Q000187:drug effects; D007928:Lethal Dose 50; D051379:Mice; D019319:Okadaic Acid / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D057096:Shellfish Poisoning; D013778:Tetrazolium Salts / Q000737:chemistry / Q000378:metabolism*; D013844:Thiazoles / Q000737:chemistry / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D004396:Coloring Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; D019319:Okadaic Acid; C022616:thiazolyl blue