Fabrication of monodisperse poly(ε-caprolactone) (PCL) particles using capillary force lithography (CFL)

This paper describes a new method for the fabrication of poly(ε-caprolactone) (PCL) spherical particles with uniform, well-controlled diameters in the range of 100 to 900 nm. This method uses capillary force lithography (CFL) technique to pattern a thin film of PCL into an array of discrete disks, followed by their transformation into spherical beads under thermal annealing. When the diameter of the disks was fixed, the size of the resultant beads was only determined by the thickness of the PCL film. To demonstrate their use in the controlled release of a drug, an organic dye was loaded into the polymer particles. The loaded dye molecules could be released with different profiles depending on the crystalline microstructure of the polymer particles.