A label-free and ratiometric fluorescent sensor based on porphyrin-metal-organic frameworks for sensitive detection of ochratoxin A in cereal

• Published in: Chinese chemical letters p. 110132
• Main Authors: Zhao, Yijian, Li, Jvzhe, Shi, Yunyi, Hu, Jie, Liu, Meiyi, Shen, Yao, Hou, Xinglin, Wang, Qiuyue, Wang, Qi, Yao, Zhiyi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2024
• Subjects: Food safety; Ochratoxin A; Porphyrinic metal-organic framework; Ratiometric fluorescent sensing; Silica nanoparticle; Silica nanoparticle; Ratiometric fluorescent sensing; Food safety; Porphyrinic metal-organic framework; Ochratoxin A
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2024.110132

The fabrication of bioreceptor-free method for accurate and sensitive detection of ochratoxin A (OTA) in cereal is critical, but still a significant challenge to mitigate risks to food industries and public health. In this study, a smartphone-ratiometric fluorescence sensor for the ultrasensitive detection of OTA is developed based on a porphyrinic metal-organic framework and silica nanoparticle composite (Zr-MOF/SiNPs) away from the use of antibodies and aptamers. Due to the excellent recognition ability of Zr-MOF and good storage stability of SiNPs, OTA is detected by Zr-MOF/SiNPs with a wide linear range of 0.05–1000 ng/mL and low detection limit of 0.016 ng/mL. Moreover, the red–blue ratio values of the fluorescence images are extracted through the smartphone color recognizer application with a limit of detection of 1.74 ng/mL, lower than the permissible content of OTA in cereal prescribed by World Health Organization. This sensing platform has been successfully applied in maize samples with superior repeatability and satisfactory recoveries, providing a novel way for simple and label-free analysis of OTA in cereal. A smartphone-ratiometric fluorescence sensor for the ultrasensitive detection of OTA in food samples is developed based on a porphyrinic metal-organic framework and silica nanoparticle composite (Zr-MOF/SiNPs) away from the use of bioreceptors [Display omitted] .