Center for Drug Evaluation and Research growing crisis around HIV testing and treatment and an inter-agency dispute between officials from the former Bureau of Drugs and officials from the former Bureau of Biologics over whether to approve Genentech's Activase (tissue plasminogen activator) led to the split. In its original form, CDER was composed of six offices: Management, Compliance, Drug Standards, Drug Evaluation I, Drug Evaluation II, Epidemiology and Biostatistics, and Research Resources. The Division of Antiviral Products was added in 1989 under Drug Evaluation II due to the large amount of drugs proposed for treating AIDS. The Office of Generic Drugs was also formed. In 2002,
Nanoparticles for drug delivery to the brain particles until the desired consistency is acquired. This manufacturing process is already scaled and in use in the food industry, which therefore makes it more appealing for researchers and for the drug delivery industry. Liposomes can also be functionalized by attaching various ligands on the surface to enhance brain-targeted delivery. Another type of lipid-nanoparticle that can be used for drug delivery to the brain is a cationic liposome. These are lipid molecules that are positively charged. One example of cationic liposomes uses bolaamphiphiles, which contain hydrophilic groups surrounding a hydrophobic chain to strengthen the boundary of the nano-vesicle containing the