Drug injection can lead to a dependency by both physical and psychological means — and develops more quickly than with other methods of taking drugs. In recreational-use drug culture, preparation may include mixing the powdered drug with water to create an aqueous solution, and then the solution is injected. This act is often colloquially referred to as "slamming", "shooting [up]", “smashing”, "banging", "pinning", or "jacking-up", often depending on the specific drug subculture in which the term is used (i.e. heroin, cocaine, or methamphetamine). There are a variety of reasons why drugs would be more attractive to inject rather than take through other
Nanoparticles for drug delivery to the brain the drug-loaded nanoparticle to circulate throughout the body for prolonged periods of time. Further, the "stealth effect", caused in part by the hydrophilic and flexible properties of the PEG chains, facilitates an increase in localizing the drug at target sites in tissues and organs. A mechanism for liposome transport across the BBB is lipid-mediated free diffusion, a type of facilitated diffusion, or lipid-mediated endocytosis. There exist many lipoprotein receptors which bind lipoproteins to form complexes that in turn transport the liposome nano-delivery system across the BBB. Apolipoprotein E (apoE) is a protein that facilitates transport of lipids and cholesterol. ApoE