Oxidized carbon nanoparticles as drug carriers

Abstract

Oxidized carbon black nanoparticles (OCBs) are successfully synthesized by modify exfoliation/oxidation process from commercially available carbon black. OCBs are 100-200 nm stable water dispersible with spherical shape. The particles contain mainly disordered π-π conjugation network of carbon atoms, with epoxide, carboxylic, and hydroxyl functionality on the surface. OCBs show no cytotoxicity against macrophage cell line (RAW 264.7), human cervical carcinoma cell line (CaSki) and keratinocyte cells, at the concentration up to 3 µg/mL, 10 µg/mL and 30 µg/mL, respectively. Experiments with cell-sized liposomes indicate that OCBs directly interact with phospholipids and induce membrane leakages. Moreover, OCBs can speed up both of micro sized and nano sized particles to association with phospholipid bilayer membranes and can increase the penetration of micro/nano particles across the membrane of the liposomes. Furthermore, experiments with cells show that OCBs can deliver a 300 kDa protein and micro/nano particles directly into cells, without an involvement of cellular endocytosis. This could be implied that the delivery by OCBs enhance the cellular penetration of bio-macromolecule and micro/nanoparticles.