Bioeliminable co-polymers based on poly(methacryloylglycylglycine-OH(x)-co-hydroxypropylmethacrylamide(y)) were successfully converted into nanoparticles by using the co-precipitation technique. Human serum albumin (HSA) and a modified (beta-cyclodextrin were used, respectively, as model protein drug and stabilizer. Nanoparticles were characterized from a dimensional and morphological point of view by means of laser diffraction granulometry and scanning electron microscopy (SEM). The prepared nanoparticles displayed a monomodal diameter distribution in the range of 130 nm, confirmed by SEM micrographs. Protein loading efficiency and drug release kinetics investigations, carried out on bioeliminable nanoparticles loaded with fluoresceinated HSA (HSA-FITC), showed that protein loading is in the range of 60% with a typical time controlled release profile. In vitro cytotoxicity investigations of the polymer matrices and resulting nanoparticles were carried out by using different assays aimed at the evaluation of the interactions of the materials with cell metabolism and the cell membrane. On the whole, bioeliminable polymers and nanoparticles resulted in high cytocompatibility thus suggesting their suitability for biomedical applications.