A simple and sensitive approach for ochratoxin A detection using a label-free fluorescent aptasensor.
Ochratoxin A(OTA) is found to be one of the predominant contaminating mycotoxins in a wide variety of food commodities. To avoid the risk of OTA consumption, the detection and quantitation of OTA level are of great significance. Based on the fact that ssDNA aptamer has the ability to form a double-strand structure with its complementary sequence, a simple and rapid aptamer-based label-free approach for highly sensitive and selective fluorescence detection of OTA was developed by using ultra-sensitive double-strand DNA specific dyes PicoGreen. The results showed that as low as 1 ng/mL of OTA could be detected with a dynamic range of more than 5 orders of magnitude which satisfies the requirements for OTA maximum residue limit in various food regulated by European Commission. With the specificity of aptamer, the assay exhibited high selectivity for OTA against two other analogues (N-acetyl-l-phenylalanine and zearalenone). We also tested the aptasensor practicability using real sample of 1% beer spiked with a series of concentration of OTA and the results show good tolerance to matrix effect. All detections could be achieved in less than 30 min, which provides a simple, quick and sensitive detection method for OTA screening in food safety and could be easily extend to other small molecular chemical compounds detection which aptamer has been selected.
College of Food Science, Sichuan Agricultural University, Ya'an, China ; Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Zhenzhen
Z
Lv
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Ailiang
A
Chen
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Jinchuan
J
Liu
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Zheng
Z
Guan
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Yu
Y
Zhou
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Siyuan
S
Xu
Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing, China ; Key Laboratory of Agri-Food Quality and Safety, Ministry of Agriculture, Beijing, China.
Shuming
S
Yang
College of Food Science, Sichuan Agricultural University, Ya'an, China.
Cheng
C
Li
D052157:Aptamers, Nucleotide / Q000378:metabolism*; D015374:Biosensing Techniques / Q000379:methods*; D002138:Calibration; D009793:Ochratoxins / Q000032:analysis*; D009930:Organic Chemicals / Q000378:metabolism; D013194:Staining and Labeling; D013997:Time Factors
D052157:Aptamers, Nucleotide; D009793:Ochratoxins; D009930:Organic Chemicals; C099476:PicoGreen; C025589:ochratoxin A