Preparation of Hydrophilic Nanoparticles of C60 with High Resistance to Aggregation during Storage, using 2-Hydroxypropyl-β-cyclodextrin
Hydrophilic nanoparticles of C 60 were prepared by co-grinding with 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD) or γ-CyD in a molar ratio 1:2 using an automatic magnetic agitating mortar for 3 h at 4 °C and reduced pressure. The nanoparticles (about 55 nm) in the γ-CyD colloidal solution were significantly aggregated during storage at 25 °C, increasing in size to about 800 nm. On the other hand, the size of the C 60 /HP-β-CyD nanoparticles (about 90 nm) remained small for 28 days. C 60 /HP-β-CyD nanoparticles had a high propensity for generating superoxide anions. HP-β-CyD is useful for preparation of hydrophilic nanoparticles of C 60 and preferred as an efficient stabilizing agent for pharmaceutical application of C 60 .