Quantitative and qualitative analysis of ochratoxin-A using fluorescent CQDs@DNA-based nanoarchitecture assembly to monitor food safety and quality

Ochratoxin A (OTA), a mycotoxin formed by various fungi, such as Aspergillus and Penicillium species, is dangerous to human health. Thus, to circumvent the risk of OTA ingestion, the recognition and quantification of OTA levels are of great significance. A perusal of the literature has revealed that the integration of DNA/Carbon Quantum Dot (CQD)-based hybrid systems may exhibit the unique electronic and optical properties of nanomaterials/nanoarchitecture and consequent recognition properties. Herein, we developed the CQDs@DNA-based hybrid nanoarchitecture system for the selective detection of OTA, which exhibits modulation in the emission spectrum after interaction with OTA, with a significant binding constant (K-a = 3.5 x 10(5) M-1), a limit of detection of 14 nM, limit of quantification of 47 nM and working range of 1-10 mu M. The mechanism for sensing the OTA has been corroborated using fluorescence, UV-visible absorption spectroscopy, and FTIR techniques, demonstrating the binding mode of CQD@DNA hybrid nano-architecture assembly with OTA. Further, we demonstrated the sensing ability of developed CQDs@DNA-based nanoarchitecture assembly towards the quantification of OTA in real food monitoring analysis for real-time applications, which makes this developed nanoarchitecture assembly the potential candidate to conveniently monitor food safety and quality for human health.

Automated summary

A DNA/Carbon Quantum Dot (CQD) based hybrid nanoarchitecture system was developed for the selective detection of Ochratoxin A (OTA). The system showed modulation in the emission spectrum after interaction with OTA, with a binding constant of 3.5 x 10(5) M-1, a limit of detection of 14 nM, limit of quantification of 47 nM, and working range of 1-10 mu M. The binding mode of the CQD@DNA hybrid nanoarchitecture assembly with OTA was confirmed using fluorescence, UV-visible absorption spectroscopy, and FTIR techniques. The system was also demonstrated to effectively quantify OTA in real food monitoring analysis, making it a potential candidate for convenient food safety and quality monitoring for human health.