High-throughput Photoactive Magnetic Microrobots for Food Quality Control.

Ensuring food quality and safety according to stringent global standards requires analytical procedures that are accurate, cost-effective, and efficient. This present innovative high-throughput microrobots designed for the detection of antioxidants in food samples. These microrobots consist of photocatalytic bismuth subcarbonate anchored on silica-coated magnetite nanoparticles. Upon exposure to UV light, they generate reactive oxygen species via photocatalysis, which oxidize the colorless dye into a green-colored radical cation. The presence of antioxidants inhibits this reaction, allowing for the quantification of antioxidant activity. The magnetic Fe₃O₄/SiO₂ core enables steering of the microrobots using a transverse rotating magnetic field, facilitating automated assays on a custom-designed 3D-printed sensing platform. This results demonstrate that these magneto-photocatalytic microrobots can perform automated, high-throughput assessments of food quality, representing a significant advancement in food analysis technology.