Quantification of ochratoxin A in a coffee sample utilizing an electrochemical aptasensor fabricated through encapsulation of toluidine blue within a Zn-based metal-organic framework.

An electrochemical aptasensor has been developed specifically for the sensitive and selective determination of ochratoxin A (OTA), one of the most important mycotoxins. The aptasensor utilizes a glassy carbon electrode that has been modified with toluidine blue (TB) encapsulated in a Zn-based metal-organic framework (TB@Zn-MOF). The results demonstrate that in the presence of OTA, the peak current of the differential pulse voltammogram (DPV) related to TB oxidation is notably decreased.

A label-free aptasensor based on electrodeposition of gold nanoparticles on silver-based metal-organic frameworks for measuring ochratoxin A in black and red pepper.

Since ochratoxin A (OTA) is immunotoxic, teratogenic and carcinogenic, it is very important to monitor this compound in food samples. In the present work, the development and fabrication of a label-free electrochemical aptasensor based on the gold nanoparticles/silver-based metal-organic framework (AuNPs/Ag-MOF) for the determination of ochratoxin A (OTA) is introduced. The aptasensor was fabricated by electrodeposition of AuNPs on a glassy carbon electrode modified with Ag-MOF.