Drug Discovery & Development
Method Of Manufacturing Micelles For Drug Delivery
Inventors: Glen Kwon, Morteza Rasoulianboroujeni, Rae Hyung Kang
UW Madison researchers have developed a novel way to manufacture large amount of micellular paclitaxel. Rather than using organic solvents to get the paclitaxel solubilized and loaded into micelles, the researchers added polyethylene glycol (PEG) to the PEG/PGA polymer and paclitaxel. The mixture was heated to 60°C to obtain a transparent liquid which was vortexed to ensure homogeneity followed by keeping the solution at 60°C for 30 min. The solution was then kept at 60°C or cooled down to 40 or 25°C and hydrated by addition of DI water with the same temperature as the solution and employing either rapid, slow or no mixing (diffusion) to form the micelles. The loaded micelles can be freeze dried without the removal of excess PEG. It can then be stored stably and rehydrated when needed. The inventors have tried PEG at various molecular weights at a weight ratio of 1:2:40 w/w/w drug/copolymer/PEG. Using PEG at 1000 molecular weight provided the best drug loading properties but also the largest micelles. The inventors found that cooling the mixture to 40°C and then diluting with water provided a better drug loading efficiency than adding the water at 60°C.