Oxidized multiwalled carbon nanotubes decorated with silver nanoparticles for fluorometric detection of dimethoate.
A novel method for the detection of dimethoate based on the peroxidase-like activity of silver-nanoparticles-modified oxidized multiwalled carbon nanotubes (AgNPs/oxMWCNTs) has been developed. The synthesized AgNPs/oxMWCNTs showed excellent peroxidease-like catalytic activity in hydrogen peroxide-Amplex red (AR) system (AR is oxidized to resorufinat, with the resorufin fluorescence at 584nm being used to monitor the catalytic activity). After dimethoate was added to AgNPs/oxMWCNTs, the interaction between dimethoate and the AgNPs inhibited the catalytic activity of AgNPs/oxMWCNTs. The decrease in fluorescence was used for the detection of dimethoate in the range of 0.01-0.35μgmL-1(R2=0.998) with a detection limit of 0.003μgmL-1(signal/noise=3). This method exhibited good selectivity for the detection of dimethoate even in the presence of high concentration of other pesticides. Consequently, the method was applied to measure the concentration of dimethoate residue in lake water and fruit, thus obtaining satisfactory results.
Department of Applied Science, National Taitung University, Taitung, Taiwan, ROC. Electronic address: chunweihsu77@gmail.com.
Chun-Wei
CW
Hsu
Department of Applied Science, National Taitung University, Taitung, Taiwan, ROC. Electronic address: a22695559@gmail.com.
Zhong-Yi
ZY
Lin
Department of Applied Science, National Taitung University, Taitung, Taiwan, ROC. Electronic address: vc7809907vc@gmail.com.
Tzu-Yi
TY
Chan
Department of Applied Science, National Taitung University, Taitung, Taiwan, ROC; Agriculture Products Inspection Center, National Taitung University, Taitung, Taiwan, ROC. Electronic address: tcchiu@nttu.edu.tw.
Tai-Chia
TC
Chiu
Department of Applied Science, National Taitung University, Taitung, Taiwan, ROC; Agriculture Products Inspection Center, National Taitung University, Taitung, Taiwan, ROC. Electronic address: cchu@nttu.edu.tw.
Cho-Chun
CC
Hu
D004117:Dimethoate / Q000032:analysis*; D005470:Fluorometry; D005504:Food Analysis; D005638:Fruit / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000378:metabolism; D060106:Lakes / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010575:Pesticides / Q000032:analysis; D012834:Silver / Q000737:chemistry*
D037742:Nanotubes, Carbon; D010575:Pesticides; D012834:Silver; D006861:Hydrogen Peroxide; D004117:Dimethoate
Carbon nanotube; Dimethoate; Nanosensor; Peroxidase-like catalyst; Silver nanoparticles