Preparation of inclusion complex of perfluorocarbon compound with β-cyclodextrin for ultrasound contrast agent

FC-77, a kind of perfluorocarbon compound, was inclusion-complexed with beta-cyclodextrin (beta-CD) in an attempt to improve their stability and bioavailability. Analyses by powder X-ray diffraction (XRD), thermogravimetric analyses (TGA), differential scanning calorimeter (DSC), Fourier transform infrared spectrum (FT-IR), transmission electron microscopy (TEM) and dynamic light scattering (DLS) proved the formation of the inclusion complex between FC-77 and beta-CD, and high performance ion chromatography revealed that FC-77 content in the inclusion complex is 9.77% at 5 : 1 molar ratio of beta-CD and FC-77. Furthermore, the inclusion constant and capacity were evaluated by UV-vis absorption spectroscopy and double reciprocal method. The results show that the nanoparticle of 1 : 1 FC-77/beta-CD inclusion complex with an inclusion constant of 242.7 M-1 was formed. Furthermore, ultrasound imaging experiments were performed to demonstrate biomedical application of FC-77/beta-CD inclusion complex, which indicated that FC-77/beta-CD inclusion complex could be employed as an ultrasound contrast agent for increasing ultrasound contrast.