Electrochemical immunoassay using quantum dot/antibody probe for identification of cyanobacterial hepatotoxin microcystin-LR.
The presence of cyanobacterial hepatotoxins such as microcystin-LR poses health threats to humans due to their potential for causing severe physiological effects when contaminated drinking water is ingested. Here, the electrochemical detection of microcystin-LR is explored using a quantum dot/antibody (QD/Ab) probe for nanoparticle-based amplification and direct electrochemical transduction. The immunological recognition of microcystin-LR using the QD/Ab probe was amplified and converted to an electrochemical signal by measuring the cadmium ions released from QD based on square wave stripping voltammetry under optimized electrochemical factors. Whereas a qualitative analysis for microcystin-LR was achieved using the specific peak potential of the anodic voltammogram at -0.6 +/- 0.05 V, concentration of the toxin was quantified based on the charge density of the anodic peak; a dynamic range of 0.227 to 50 microg/L and limit of detection of 0.099 microg/L were obtained with high sensitivity. The extracted microcystin-LR from Microcystis aeruginosa was estimated as 1,944 microg/g of dried weight of the microorganism.
Yu
Hye-Weon
HW
Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712, Korea.
Lee
Jinwook
J
Kim
Sungyoun
S
Nguyen
Giang Huong
GH
Kim
In S
IS
D000911:Antibodies, Monoclonal / Q000276:immunology; D015374:Biosensing Techniques / Q000379:methods*; D002104:Cadmium / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D007118:Immunoassay / Q000379:methods*; D008387:Marine Toxins; D052998:Microcystins / Q000032:analysis* / Q000276:immunology / Q000302:isolation & purification; D046931:Microcystis / Q000737:chemistry* / Q000166:cytology; D045663:Quantum Dots; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; D008387:Marine Toxins; D052998:Microcystins; D002104:Cadmium; C057862:cyanoginosin LR