Atezolizumab-Conjugated Poly(lactic acid)/Poly(vinyl alcohol) Nanoparticles as Pharmaceutical Part Candidates for Radiopharmaceuticals.

The necessity of new drugs for lung cancer therapy and imaging is increasing each day. The development of new drugs that are capable of reaching the tumor with specificity and selectivity is required. In this direction, the design of nanoparticles for tumor therapy represents an important alternative. The aim of this study was to develop, characterize, and evaluate target-specific atezolizumab-conjugated poly(lactic acid)/poly(vinyl alcohol) (PLA/PVA) nanoparticles as pharmaceutical fragment candidates for new radiopharmaceuticals. For this purpose, PLA/PVA nanoparticle formulations were prepared by the double emulsification/solvent evaporation method with a high-speed homogenizer. A special focus was oriented to the selection of a suitable method for modification of the nanoparticle surface with a monoclonal antibody. For this purpose, atezolizumab was bound to the nanoparticles during the preparation by solvent evaporation or either by adsorption or covalent binding. PLA/PVA/atezolizumab nanoparticles are characterized by dynamic light scattering, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. An in vitro assay was performed to evaluate the antibody binding efficiency, stability, and cytotoxicity [A549 (lung cancer cell) and L929 (healthy fibroblast cell)]. The results showed that a spherical nanoparticle with a size of 230.6 ± 1.768 nm and a ζ potential of -2.23 ± 0.55 mV was produced. Raman spectroscopy demonstrated that the monoclonal antibody was entrapped in the nanoparticle. The high antibody binding efficiency (80.58%) demonstrated the efficacy of the nanosystem. The cytotoxic assay demonstrated the safety of the nanoparticle in L929 and the effect on A549. In conclusion, PLA/PVA/atezolizumab nanoparticles can be used as drug delivery systems for lung cancer diagnosis and therapy.