In situ observation of C 60 (C(COOH) 2 ) 2 interacting with living cells using fluorescence microscopy

The interactions between nanoparticles and living cells were investigated by an imaging technique of fluorescence microscopy. For this purpose, the C 60 derivative C 60 (C(COOH) 2 ) 2 , a therapeutic agent for degeneration diseases of central nervous system, was synthesized, purified and characterized. Its interaction with the living cell and penetration of the cellular membrane were in situ studied using the real time imaging technique, and its potential cytotoxicity was also examined by flow cytometry. The results indicate that C 60 (C(COOH) 2 ) 2 can easily enter cells, and is mainly located in cytoplasm by fluorescein labeling. Furthermore, C 60 (C(COOH) 2 ) 2 can carry the molecule that cannot cross cellular membranes into cells, because fluorescein compound itself cannot enter the cell or adhere to membrane. At concentrations ranging from 1 × 10 −2 to 1 × 10 2 mg/L, C 60 (C(COOH) 2 ) 2 does not show any detectable cytotoxicity.