The blood-brain barrier, a formidable obstacle that impedes the entry of drugs into the central nervous system, presents significant challenges in the treatment of neurodegenerative diseases and brain cancer. In a groundbreaking development, scientists have crafted a novel delivery system, drawing inspiration from the brain's intricate iron supply mechanism. This innovative system is capable of traversing the blood-brain barrier and delivering antibodies, proteins, and gene therapeutic drugs to the brain with pinpoint accuracy. This versatile system can transport a wide array of biological agents, encompassing oligonucleotides and gene editing tools, and some of these technologies have already advanced to the clinical stage, heralding new horizons in the treatment of brain disorders.