{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T01:22:40Z","timestamp":1776129760060,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,7,28]],"date-time":"2019-07-28T00:00:00Z","timestamp":1564272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Major Scientific and Technological Special Project for \u201cSignificant New Drugs Development\u201d","award":["No. 2018ZX09201010, 2013ZX09402203"],"award-info":[{"award-number":["No. 2018ZX09201010, 2013ZX09402203"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>With the widespread contamination of ochratoxin A (OTA), it is of significant importance for detecting OTA in foods and traditional Chinese medicine (TCM). In this study, a novel label-free fluorescent aptasensor utilizing the interaction between OTA-triggered antiparallel G-quadruplex and (N-methyl-4-pyridy) porphyrin (TMPyP) for the rapid and sensitive determination of OTA was established. The fluorescence of CdTe quantum dots (QDs) could be quenched by TMPyP. In the presence of analyte (OTA), the aptamer could recognize OTA and transform from a random coil to the antiparallel G-quadruplex. The interaction between G-quadruplex and TMPyP could release CdTe QDs from TMPyP, and thus recover the fluorescence of CdTe QDs. Under optimized conditions, the detection limit of the designed aptasensor was 0.16 ng mL\u22121, with a linear range of 0.2 to 20 ng mL\u22121. Furthermore, this aptasensor showed high selectivity toward OTA against other structural analogs and other mycotoxins, and was successfully applied in Astragalus membranaceus samples. The presented aptasensor for OTA detection could be a promising tool for the field monitoring of food and TCM.<\/jats:p>","DOI":"10.3390\/toxins11080447","type":"journal-article","created":{"date-parts":[[2019,7,29]],"date-time":"2019-07-29T03:06:58Z","timestamp":1564369618000},"page":"447","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Label-Free Fluorescent Aptasensor for Ochratoxin\u2014A Detection Based on CdTe Quantum Dots and (N-Methyl-4-pyridyl) Porphyrin"],"prefix":"10.3390","volume":"11","author":[{"given":"Li","family":"Liu","sequence":"first","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zafar Iqbal","family":"Tanveer","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keqiu","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qingwen","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinghui","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0246-9067","authenticated-orcid":false,"given":"Yongjiang","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zheng","family":"Han","sequence":"additional","affiliation":[{"name":"Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-products (Shanghai), Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1112","DOI":"10.1038\/2051112a0","article-title":"Ochratoxin A, a Toxic Metabolite produced by Aspergillus ochraceus Wilh","volume":"205","author":"Steyn","year":"1965","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Malir, F., Ostry, V., Pfohl-Leszkowicz, A., Malir, J., and Toman, J. 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