Liposomes are a promising method for delivering therapeutic agents to their destinations without first exposing them to the rest of the body. These vesicles, made from a dual layer of lipid molecules and often surrounded by a protective coating, have been difficult to produce consistently in large numbers. This has slowed the development of the technology, but researchers from the National Institute of Standards and Technology (NIST) have developed a new device that manufactures liposomes in quantities, all the same size and shape.
The 3D microfluidic device consists of seven glass capilary tubes each one a millimeter in diameter, with the center one having an even narrower tube running through it. By running a solution called PBS through the six outer tubes while a solution of phospholipid dissolved in alcohol is pushed through the center, the result at the end are liposomes tuned to be the same size.
From the study abstract in Lab on a Chip:
A novel microscale device has been developed to enable the one-step continuous flow assembly of monodisperse nanoscale liposomes using three-dimensional microfluidic hydrodynamic focusing (3D-MHF) in a concentric capillary array. The 3D-MHF flow technique displays patent advantages over conventional methods for nanoscale liposome manufacture (i.e., bulk-scale alcohol injection and/or sonication) through the on-demand synthesis of consistently uniform liposomes without the need for post-processing strategies. Liposomes produced by the 3D-MHF device are of tunable size, have a factor of two improvement in polydispersity, and a production rate that is four orders of magnitude higher than previous MHF methods, which can be attributed to entirely radially symmetric diffusion of alcohol-solvated lipid into an aqueous flow stream. Moreover, the 3D-MHF platform is simple to construct from low-cost, commercially-available components, which obviates the need for advanced microfabrication strategies necessitated by previous MHF nanoparticle synthesis platforms.