Production of a broad specificity antibody for the development and validation of an optical SPR screening method for free and intracellular microcystins and nodularin in cyanobacteria cultures.
A highly sensitive broad specificity monoclonal antibody was produced and characterised for microcystin detection through the development of a rapid surface plasmon resonance (SPR) optical biosensor based immunoassay. The antibody displayed the following cross-reactivity: MC-LR 100%; MC-RR 108%; MC-YR 68%; MC-LA 69%; MC-LW 71%; MC-LF 68%; and Nodularin 94%. Microcystin-LR was covalently attached to a CM5 chip and with the monoclonal antibody was employed in a competitive 4 min injection assay to detect total microcystins in water samples below the WHO recommended limit (1 µg/L). A 'total microcystin' level was determined by measuring free and intracellular concentrations in cyanobacterial culture samples as this toxin is an endotoxin. Glass bead beating was used to lyse the cells as a rapid extraction procedure. This method was validated according to European Commission Decision 96/23/EC criteria. The method was proven to measure intracellular microcystin levels, the main source of the toxin, which often goes undetected by other analytical procedures and is advantageous in that it can be used for the monitoring of blooms to provide an early warning of toxicity. It was shown to be repeatable and reproducible, with recoveries from spiked samples ranging from 74 to 123%, and had % CVs below 10% for intra-assay analysis and 15% for inter-assay analysis. The detection capability of the assay was calculated as 0.5 ng/mL for extracellular toxins and 0.05 ng/mL for intracellular microcystins. A comparison of the SPR method with LC-MS/MS was achieved by testing six Microcystis aeruginosa cultures and this study yielded a correlation R(2) value of 0.9989.
Institute for Global Food Security (IGFS), School of Biological Sciences, Queen's University Belfast, 18-30 Malone Road, Belfast BT9 5BN, UK.
Shauna
S
Devlin
Institute for Global Food Security (IGFS), School of Biological Sciences, Queen's University Belfast, 18-30 Malone Road, Belfast BT9 5BN, UK.
Julie P
JP
Meneely
Institute for Global Food Security (IGFS), School of Biological Sciences, Queen's University Belfast, 18-30 Malone Road, Belfast BT9 5BN, UK.
Brett
B
Greer
Institute for Global Food Security (IGFS), School of Biological Sciences, Queen's University Belfast, 18-30 Malone Road, Belfast BT9 5BN, UK.
Katrina
K
Campbell
Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
Vitor
V
Vasconcelos
Institute for Global Food Security (IGFS), School of Biological Sciences, Queen's University Belfast, 18-30 Malone Road, Belfast BT9 5BN, UK. Electronic address: Chris.Elliott@qub.ac.uk.
Christopher T
CT
Elliott
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism*; D000458:Cyanobacteria / Q000737:chemistry / Q000378:metabolism*; D007424:Intracellular Fluid / Q000737:chemistry / Q000378:metabolism* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D052998:Microcystins / Q000032:analysis / Q000378:metabolism*; D046931:Microcystis / Q000737:chemistry / Q000378:metabolism; D010456:Peptides, Cyclic / Q000032:analysis / Q000378:metabolism*; D015203:Reproducibility of Results; D020349:Surface Plasmon Resonance / Q000379:methods* / Q000592:standards
D000911:Antibodies, Monoclonal; D052998:Microcystins; D010456:Peptides, Cyclic; C063998:nodularin
Blue-Green Algae cultures; Cyanobacteria; Freshwater; Microcystin; Nodularin; SPR