Pollen-Based Magnetic Microrobots are Mediated by Electrostatic Forces to Attract, Manipulate, and Kill Cancer Cells

Naturally occurring micro/nanoparticles provide an incredible array of potential sources when preparing hybrid micro/nanorobots and their intrinsic properties can be exploited as multitasking functionalities of modern robotics as well as ensuring their mass production availability. Herein, magnetic biological bots (BioBots) prepared from defatted sunflower pollen microparticles by ferromagnetic metal layer evaporation on one side of its surface are described. It is demonstrated that the methodology employed introduces magnetic properties to sunflower pollen microparticles-based BioBots and enable their magnetic actuation. Interestingly, as-prepared magnetic sunflower pollen-based BioBots can naturally attract cancer cells due to their opposite charges (positive and negative, respectively). Such attracted cancer cells can then be transported by microrobots. This strong attraction also allows the delivery of drugs intended to kill the cancer cells. Sunflower-based BioBots can be fabricated in large quantities, and are naturally programmable, making them promising candidates for cancer cell therapy.