title: Automated, high performance, flow-through chemiluminescence microarray for the multiplexed detection of phycotoxins.
abstract: A novel multiplexed immunoassay for the analysis of phycotoxins in shellfish samples has been developed. Therefore, a regenerable chemiluminescence (CL) microarray was established which is able to analyze automatically three different phycotoxins (domoic acid (DA), okadaic acid (OA) and saxitoxin (STX)) in parallel on the analysis platform MCR3. As a test format an indirect competitive immunoassay format was applied. These phycotoxins were directly immobilized on an epoxy-activated PEG chip surface. The parallel analysis was enabled by the simultaneous addition of all analytes and specific antibodies on one microarray chip. After the competitive reaction, the CL signal was recorded by a CCD camera. Due to the ability to regenerate the toxin microarray, internal calibrations of phycotoxins in parallel were performed using the same microarray chip, which was suitable for 25 consecutive measurements. For the three target phycotoxins multi-analyte calibration curves were generated. In extracted shellfish matrix, the determined LODs for DA, OA and STX with values of 0.5±0.3 μg L(-1), 1.0±0.6 μg L(-1), and 0.4±0.2 μg L(-1) were slightly lower than in PBS buffer. For determination of toxin recoveries, the observed signal loss in the regeneration was corrected. After applying mathematical corrections spiked shellfish samples were quantified with recoveries for DA, OA, and STX of 86.2%, 102.5%, and 61.6%, respectively, in 20 min. This is the first demonstration of an antibody based phycotoxin microarray.
authors.affiliation: Institute of Hydrochemistry and Chair for Analytical Chemistry, Technische Universität München, 81377 Munich, Germany.
authors.forename: Agathe
authors.initials: A
authors.lastname: Szkola
authors.forename: Katrina
authors.initials: K
authors.lastname: Campbell
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Elliott
authors.forename: Reinhard
authors.initials: R
authors.lastname: Niessner
authors.forename: Michael
authors.initials: M
authors.lastname: Seidel
mesh_terms: D000818:Animals; D002417:Cattle; D007608:Kainic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D049449:Luminescence; D008387:Marine Toxins / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D046228:Microarray Analysis / Q000379:methods*; D019319:Okadaic Acid / Q000032:analysis*; D012530:Saxitoxin / Q000032:analysis*; D012758:Shellfish; D057096:Shellfish Poisoning / Q000175:diagnosis / Q000517:prevention & control
chemical_list: D008387:Marine Toxins; D019319:Okadaic Acid; D012530:Saxitoxin; C012301:domoic acid; D007608:Kainic Acid
keywords: Automated system; Chemiluminescence detection; Multiplex immunoassay; Phycotoxins; Regenerable immunochip