Controlled drug delivery (CDD) systems offer numerous advantages compared to conventional dosage forms including improved efficiency, reduced toxicity, and improved patient compliance, therefore, a wide range of drug-loaded nanoparticles (NPs) have been used. Drug-loaded NPs are prepared directly from preformed polymers or by emulsion polymerization; this last method having the advantage to be a one-pot process that allows high-solid-content latex without any further concentration step and a better control of the particles size. In the case of water-sensitive polymerization mechanisms, such as anionic ring-opening polymerization (ROP) of ε-caprolactone (CL), a non-aqueous emulsion polymerization is necessary. Drug-loaded new biomaterials based on NPs will be prepared by non-aqueous emulsion polymerizations with a biocompatible continuous phase. In these oil-in-oil emulsions, the stabilization will be achieved by using tailor-made biocompatible block copolymers. Two anticancer drugs, one hydrophobic and another hydrophilic, will be encapsulated in the NPs during the polymerization process. As an extension of this strategy, two-phase biomaterials will be synthesized by the photopolymerization of the continuous phase. The drug release rates will be determined as a function of the NPs characteristics. Moreover, in vitro cytotoxicity tests of these biomaterials will be realized using three cancer cell lines, such as skin, breast and lung.