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

Glioblastoma, 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. Active drug delivery approaches using tumor-targeted nanomotors with the ability to actively bypass the blood-brain barrier (BBB) can enhance the permeability and accumulation of carried drugs into the 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, such as chemotactic nanomotors, near-infrared (NIR) light-driving nanomotors, and bubble-driving nanomotors, to specifically target and treat glioblastomas. With their moving ability, such nanomotors provide superior bio-performances including cellular uptake, BBB crossing, and deep tumor penetration and accumulation. In this systematic review, the recent advances in the treatment of glioblastomas with nanomotors are described, and the mechanisms underlying their driving mode for penetrating and targeting glioblastomas are discussed.