Nanomotor-mediated drug delivery with efficient blood-brain barrier crossing for active targeting and therapy of glioblastoma: A systematic review

Glioblastoma, as a primary brain tumor, is the most prevalent and destructive intracranial tumor, and its therapeutics are restricted by insufficient doses and toxicity, resulting from classical drug delivery systems using passive delivery. The active drug delivery approaches using tumor-targeted nanomotors with the ability to actively bypass blood-brain barriers (BBB) can enhance the permeability and accumulation of carried drugs into brain tumors. Nanomotors show self-propelled motion that enables them to autonomously navigate within biological fluids and efficiently penetrate across the blood vessels and BBB, thereby reducing systemic side effects and improving the efficacy of the administered dosage in the brain tumor. Several experimental studies have recently developed various functionalized nanomotors to specifically target and treat glioblastoma, chemotactic nanomotors, near-infrared (NIR) light-driving nanomotors, and bubble-driving nanomotors. With moving ability, such nanomotors provide superior bio-performances, including cellular uptake, BBB crossing, as well as deep tumor penetration and accumulation. In the present systematic review, recent advances in the treatment of glioblastoma with nanorobots are described, and mechanisms underlying their driving mode for penetrating and targeting glioblastoma are discussed.