History of neuroscience that the functional unit of the brain is the neuron. Golgi and Ramón y Cajal shared the Nobel Prize in Physiology or Medicine in 1906 for their extensive observations, descriptions and categorizations of neurons throughout the brain. The hypotheses of the neuron doctrine were supported by experiments following Galvani's pioneering work in the electrical excitability of muscles and neurons. In the late 19th century, Emil du Bois-Reymond, Johannes Peter Müller, and Hermann von Helmholtz showed neurons were electrically excitable and that their activity predictably affected the electrical state of adjacent neurons. In parallel with this research, work with brain-damaged patients
Nanoparticles for drug delivery to the brain that it can bind and undergo endocytosis. Another mechanism is "adsorption mediated transcytosis", where electrostatic interactions are involved in mediating nanoparticle crossing of the BBB. Cationic nanoparticles (including cationic liposomes) are of interest for this mechanism, because their positive charges assist binding on the brain's endothelial cells. Using TAT-peptides, a cell-penetrating peptide, to functionalize the surface of cationic nanoparticles can further improve drug transport into the brain. In contrast to the above mechanisms, a delivery with magnetic fields doesn't strongly depend on the biochemistry of the brain. In this case, nanoparticles are literally pulled across the BBB via application of