title: A semi-quantitative dipstick assay for microcystin.
abstract: An immunochromatographic lateral flow dipstick assay for the fast detection of microcystin-LR was developed. Colloid gold particles with diameters of 40 nm were used as red-colored antibody labels for the visual detection of the antigen. The new dipstick sensor is capable of detecting down to 5 microg x l(-1) (ppb; total inversion of the color signal) or 1 ppb (observation of color grading) of microcystin-LR. The course of the labeling reaction was observed via spectrometric wave shifts caused by the change of particle size during the binding of antibodies. Different stabilizing reagents showed that especially bovine serum albumin (BSA) and casein increase the assays sensitivity and the conjugate stability. Performance of the dipsticks was quantified by pattern processing of capture zone CCD images. Storage stability of dipsticks and conjugate suspensions over 115 days under different conditions were monitored. The ready-to-use dipsticks were successfully tested with microcystin-LR-spiked samples of outdoor drinking- and salt water and applied to the tissue of microcystin-fed mussels.
authors.affiliation: Institute of Bioprocess Engineering, Department of Mechanical & Process Engineering, University of Kaiserslautern, Gottlieb-Daimler-Str. 44, 67663, Kaiserslautern, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Tippkötter
authors.forename: Henning
authors.initials: H
authors.lastname: Stückmann
authors.forename: Stephen
authors.initials: S
authors.lastname: Kroll
authors.forename: Gunda
authors.initials: G
authors.lastname: Winkelmann
authors.forename: Udo
authors.initials: U
authors.lastname: Noack
authors.forename: Thomas
authors.initials: T
authors.lastname: Scheper
authors.forename: Roland
authors.initials: R
authors.lastname: Ulber
mesh_terms: D000906:Antibodies / Q000737:chemistry; D000937:Antigen-Antibody Reactions; D002364:Caseins / Q000737:chemistry; D002845:Chromatography / Q000379:methods*; D003102:Colloids / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D007118:Immunoassay / Q000379:methods*; D052998:Microcystins / Q000032:analysis*; D010316:Particle Size; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry
chemical_list: D000906:Antibodies; D002364:Caseins; D003102:Colloids; D052998:Microcystins; D012710:Serum Albumin, Bovine; D006046:Gold