Liposomes were first discovered in 1960 by British scientist Alec Bangham and his colleagues. These researchers found that egg lecithin could react with water to form intricate structures. Electron microscopes showed that these vesicles could form almost spontaneously, and these lipid vesicles were then termed “smetic mesophases”. At first, these liposomes were only used to serve as cell models to allow for research of cellular membranes and transport mechanisms. Since liposomes had a similar structure to cell membranes, this comparison proved effective. However, liposomes were soon discovered to be a candidate for drug delivery systems and other medical applications. The scope of liposomes began to expand, ranging from cosmetics products to medical testing to agriculture. In the early 1970s, the physiochemical characterization of liposomes was carried out, and a novel hydration method was created to generate multilamellar vesicles (MLVs). By the early 1980s, the liposomal structure had been reengineered to guarantee stability and allow the liposomes to circulate in the blood for a longer period of time. Stealth liposomes were also designed to deliver pharmaceutical drugs directly to the cells. [Citation 13] [Citation 14] [Citation 15] [Citation 20] [Citation 21] [Citation 22]

 

      Liposome development and commercialization were hampered by two main difficulties. First, it was difficult to produce large quantities of liposomes in a reproducible and controlled manor. Second, the clinical trials conducted with liposomes were not successful at first because the liposomes were not stable enough to deliver drugs. However, by 1990, new industrial mechanisms allowed for the creation of stable liposomes that could effectively deliver drugs into the human body. The first products released on the market utilizing liposome nanoparticle technology were Doxil and DaunoXome as anticancer drugs. After successful clinical trials, the United States Food and Drug Administration approved the drugs in 1990. However, in total, it took about 10 years and over 100 million dollars to bring these liposomal drugs from the lab bench to the commercial market. [Citation 16] [Citation 17]

 

 

 

 

      After the turn of the century, both the European Agency of the Evaluation of Medical Products (EMA) and the U.S. Food and Drug Administration have addressed liposomes as a novel drug delivery mechanism and have implement liposomes into their guidelines. There are many drugs that exist today that utilize liposome nanoparticle technology, as shown in the graph below. [Citation 18] [Citation 19]​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​