Cu/Au/Pt trimetallic nanoparticles coated with DNA hydrogel as target-responsive and signal-amplification material for sensitive detection of microcystin-LR.
Sensitive and reliable analytical methods for monitoring of microcystin-LR (MC-LR) are urgently necessary due to its great harm to human health and aquatic organisms. In this work, a novel Cu/Au/Pt trimetallic nanoparticles (Cu/Au/Pt TNs)-encapsulated DNA hydrogel was prepared for colorimetric detection of MC-LR. The Cu/Au/Pt TNs were captured and released with precise control by the target-responsive 3D DNA hydrogels, which combined dual advantages of the target responsive DNA hydrogel and Cu/Au/Pt TNs of enhanced peroxidase-like activity. The DNA hydrogel network was constructed by hybridizing MC-LR aptamer with two complementary DNA strands on linear polyacrylamide chains. As long as MC-LR presented, the aptamer competitively binds with the MC-LR, causing the hydrogel to dissolve and release the preloaded Cu/Au/Pt TNs which could catalyze the reaction between H2O2 and TMB to produce color changes. In view of this sensitive strategy, this Cu/Au/Pt TNs-encapsulated DNA hydrogel-based colorimetric biosensor can achieve quantitative determination of MC-LR. The results showed that as-proposed colorimetric biosensor could sensitively detect MC-LR with a linear range of 4.0-10000 ng L-1 and a detection limit of 3.0 ng L-1. This work proved that the sensor had great potential to be applied in MC-LR detection and also provided the opportunity to develop colorimetric biosensor for other targets using this target-responsive and signal-amplification strategy.
['Wu|Pian|P|', 'Li|Shuang|S|', 'Ye|Xiaosheng|X|', 'Ning|Baoan|B|', 'Bai|Jialei|J|', 'Peng|Yuan|Y|', 'Li|Lei|L|', 'Han|Tie|T|', 'Zhou|Huanying|H|', 'Gao|Zhixian|Z|', 'Ding|Ping|P|']
D052157:Aptamers, Nucleotide D015374:Biosensing Techniques D004247:DNA D006046:Gold D020100:Hydrogels D006861:Hydrogen Peroxide D057230:Limit of Detection D008387:Marine Toxins D053768:Metal Nanoparticles D052998:Microcystins
Cu/Au/Pt trimetallic nanoparticles DNA hydrogel Detection Microcystin-LR Signal amplification