Non-spherical racemic polylactide microarchitectures formation via solvent evaporation method

Usually, amphiphilic or crystalline structure is necessary to prepare nano- or micro-structured materials with various morphologies. Racemic random polylactide (PDLLA) is completely amorphous in nature and was mainly prepared to be of spherical form for the use of sustained drug release. In this paper, we observed novel lath-, sheaf-like morphologies of PDLLA microarchitectures fabricated by the double emulsion-solvent evaporation method in the presence of glycerol or epirubicin. These non-spherical microarchitectures coexisted with amorphous PDLLA microspheres and crystallized poly(vinyl alcohol) (PVA) nanoparticles. On the basis of our experiments, the formation of lath-like microarchitectures is due to glycerol, while the formation of sheaf-like microarchitectures is owing to both glycerol and epirubicin. Therefore, novel assemblies of PDLLA have been developed and the formation mechanism is different from those of well-defined amphiphilic or crystalline polymers. These PDLLA non-spherical microarchitectures might have potential application as non-spherical carriers in drug delivery system.