Controllable Synthesis of Horseradish Peroxidase Loaded Poly(D,L-lactide) Nanospheres

In this work, horseradish peroxidase (HRP), a model protein, was encapsulated by the precipita-tion method with additional step of homogenization, using polymer poly(D,L-lactide) (PDLLA). The purpose of this study was to expand the application of a modified precipitation method to HRP-loaded PDLLA spheres and to find optimal conditions for preparing HRP-loaded PDLLA spheres with the best properties, with size under 1000 nm. Influence of process variables on the size and morphology of the particles has been studied. Size of the spheres depends on homogenization speed, co-solvent selection, chloroform to water ratio and PVA concentration. Particle size was ranging between 460 nm and 1130 nm, according to the preparation conditions. The optimized con-ditions yielded nanospheres with 46 % encapsulation efficiency and average diameter of 530 nm. A particle size under 1000 nm enables intravascular injection and is also desirable for intramuscular and subcutaneous administration, minimizing possible irritant reactions. It was found that modified precipitation method was widely applicable to HRP-loaded PDLLA spheres, by choosing optimal preparation conditions. Keywords: 1