Mycotoxins, such as fumonisins and ochratoxins, are potent toxins produced by fungi. They can cause harmful effects on animal and human health. Therefore, selective, sensitive, fast, portable, and easy-to-use methods for the detection of these toxins are needed.

Alberto Escarpa and colleagues, University of Alcalá, Madrid, Spain, have studied the use of magnetic reduced graphene oxide/nickel/platinum nanoparticle (rGO/Ni/PtNPs) micromotors for food safety diagnosis. The strategy is based on the self-propelled movement of the micromotors around an extremely low sample volume.

After biological interaction with the target mycotoxin, the outer layer (rGO) of the micromotors allows the selective adsorption of free aptamers (oligonucleotide or peptide molecules that bind to a specific target molecule). The inner layer (PtNPs) allows for the propulsion of the motor to make it swim through the sample, and the intermediate magnetic layer (Ni) makes it possible to control the motor movement and analyze the performance.

The mixing effect and autonomous movement of the motors around the sample to find the free aptamers allows for the selective analysis of target mycotoxins in a very short time (2 min) and using extremely low sample volumes (<10 µL) with excellent sensitivity and accuracy. According to the researchers, their results are promising for applications of these micromotors in fields such as food safety analysis.

• Magnetic Reduced Graphene Oxide/Nickel/Platinum Nanoparticles Micromotors for Mycotoxin Analysis,
  Águeda Molinero-Fernández, Adrián Jodra, María Moreno-Guzmán, Miguel Ángel López, Alberto Escarpa,
  Chem. Eur. J. 2018.
  https://doi.org/10.1002/chem.201706095