Fig. 8From: Caffeine-folic acid-loaded-chitosan nanoparticles combined with methotrexate as a novel HepG2 immunotherapy targeting adenosine A2A receptor downstream cascadeTransmission electron microscopy of the optimal formulations of CS-NPs (a), CAF-CS-NPs (b), FA-CS-NPS (c), and CAF-FA-CS-NPs (d). (Scale bar is 200Â nm and 100Â nm)Back to article page