FOOD CHEMISTRY
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2024
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IF 8.5
Xiaokun Wang,Hao Ding,Yinghui Sun,Yanling Ma,Guoqing Wang,Jiadong Chen,Jaebum Choo,Lingxin Chen
To address the need for highly sensitive and reliable detection of trace ochratoxin A (OTA) in food matrices, we developed a ratiometric fluorescent aptasensor by integrating CRISPR/Cas12a, hybridization chain reaction (HCR), and horseradish peroxidase (HRP)-induced inner filter effect (IFE). The mechanism involves OTA releasing an activator that initiates CRISPR/Cas12a trans-cleavage, blocking HCR assembly. This reduces HRP levels, limiting the conversion of o -phenylenediamine (OPD) to fluorescent 2,3-diaminophenazine (DAP) (emitting at 562 nm) while maintaining strong emission from 2-amino terephthalic acid (BDC-NH 2 ) at 426 nm. The F 426 /F 562 ratio serves as a “signal-on” indicator, enabling sensitive OTA detection over 0.1 pM to 10 nM, with a detection limit of 0.0417 pM. The method exhibits excellent reproducibility, with intra-day and inter-day relative standard deviations (RSDs) of 1.91 %–3.87 % and 1.79 %, respectively, along with recovery rates of 90.1 %–110.6 % in real samples. These advantages highlight its significant potential for CRISPR/Cas-based OTA detection.
研究领域:
食品安全
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分子生物学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Xiao Liang,Qiu-Lan Li,Ji-Tao Li,Wen-Bo Zhao,De-Zhi Yang,Ya-Ling Yang,Zi-Tao Zhong
Ochratoxin A (OTA) is recognized as a Group 2B carcinogen and poses significant dangers to human, making it crucial to regulate OTA levels in food products. Herein, we developed a colorimetric approach to analyze OTA utilizing the intrinsic catalytic oxidized activity of Fe 3 O 4 magnetic nanoparticles (MNPs). Our findings reveal that OTA shows a significant impact on the absorbance signal of the catalytic system, notably reducing the absorbance at 532 nm with H 2 O 2 and 4-aminoantipyrene (4-AP). This sensor does not require elaborate aptamer or antibody, omitting the cumbersome reaction and the loss during synthesis, thus simply realizing OTA detection. The signal correlates linearly with the OTA concentrations and achieves satisfied sensitivity. The practical application has been verified utilizing beer and rice samples, resulting in recoveries ranging from 91.0 % to 106.2 %. This accuracy and reliability verified the method feasibility for monitoring OTA levels in food products.
研究领域:
食品科学
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分析化学
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毒理学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Meng Xu,Yimeng Li,Xiaopeng Hu,Shuai Zhang,Yiwei Liu
A smartphone-assisted colorimetric aptasensor was constructed for the detection of ochratoxin A (OTA) utilizing Au/CeO₂/rGO nanohybrid. The sensor integrates aptamer-functionalized Au/Fe 3 O 4 (Apt/Au/Fe 3 O 4 ) as recognition elements. The complementary-chain-modified Au/CeO₂/rGO (cDNA/Au/CeO₂/rGO) act as nanozyme catalyst for signal amplification through the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to blue-colored ox-TMB. The detection mechanism relies on competitive binding between OTA and cDNA/Au/CeO 2 /rGO to Apt/Au/Fe 3 O 4 . Upon OTA introduction, OTA preferentially binds to Apt/Au/Fe 3 O 4 . These Apt/Au/Fe 3 O 4 are magnetically separated and introduced into the cDNA/Au/CeO 2 /rGO suspension. Unbound Apt/Au/Fe 3 O 4 interacts with cDNA/Au/CeO 2 /rGO. After magnetic separation, the residual cDNA/Au/CeO 2 /rGO concentration in supernatant exhibits a correlation with the OTA concentration. This design effectively eliminates potential interference from the intrinsic color of coffee, significantly improving the accuracy of colorimetric detection. The aptasensor demonstrated superior selectivity towards OTA with a detection limit of 27.3 pg mL −1 . This specificity was validated against interference, with recovery rates of 102.1–117.4 % in coffee, as confirmed by ELISA.
研究领域:
食品安全
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分析化学
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纳米技术
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生物传感器
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毒素检测
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适配体技术
✓ 已验证
产品关联
DOI
高影响因子
FOOD CONTROL
·
2023
·
IF 6
Chenfei Han,Yu Xiao,Zhenjiang Liu,Daolin Du,Ming Li
To improve the performance of aptasensor, the coupling of novel material and strategy had been the hottest research with the promising prospects. In this study, a cascade amplifying aptasensor (CA-aptasensor), which had coupled the DNase I-assisted cyclic enzyme digestion and AgNPs@gel-enhanced fluorescence, had reflected the desired performance for positively correlated detecting OTA . For this purpose, the GO@PVP was used to adsorb and quench the free FAM-Apt, while the complex of OTA and FAM-Apt was digested by the DNase I. The released OTA allowed the free FAM-Apt to separate from the GO@PVP cyclically, thus the OTA level was amplified preliminarily. The AgNPs@gel could combine with the released FAM to form the metal enhanced fluorescence (MEF) effect, resulting in the cascade signal amplification. The OTA was detected at pg mL −1 level with an ultrasensitive LOD of 3.33 pg mL −1 and IC 50 of 13.6 pg mL −1 , which improved 90-fold and 728-fold than that of ELASA for same aptamer. The CA-aptasensor indicated high specificity, reliability and practicability. Meanwhile, the CA-aptasensor exhibited more highlights, including the efficient homogeneous system, low background signal and standardized aptamer recognizer. This study might provide a new approach for improving the performance of aptasensor, which could also guide the signaling cascade and positively correlated detection for other risk factors.
研究领域:
分析化学
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生物传感器
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纳米技术
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食品安全
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）