Monodisperse microspheres for drug delivery systems

A major application field for microspheres is controlled drug delivery. Typically an active pharmaceutical ingredient such as a protein or peptide is homogeneously distributed in the matrix of a biodegradable polymer microsphere. The most commonly used materials for these systems are polylactide (PLA) and its copolymers with glycolide (PLGA). The usual production method for these spheres is the conventional emulsification of a solution of the polymer and the active pharmaceutical ingredient followed by solvent evaporation. Generally this process result in spheres with a large size distribution.

Our technology offers the opportunity to reproducibly make monodisperse drug delivery microspheres of specified size, often with the same formulation as used for the preparation with conventional technology. In addition the technology allows for the use of heat and shear sensitive ingredients and can be easily scaled-up under cGMP conditions.

As an example, the upper picture shows monodisperse PLA microspheres of 10 micron diameter made from a PLA in dichloromethane (DCM) solution. The lower picture shows monodisperse biodegradable microspheres with a protein encapsulated that was labeled with a fluorescent marker.