Abstract
Purpose Here we report the development of quantiosomes, niosomes formed from Span 60, cholesterol, and quantum dots (QDs), for achieving sensitive bioimaging and anticancer drug delivery.
Methods The nanocarriers were further modified by incorporating soy phosphatidylcholine (SPC), polyethylene glycol (PEG), or cationic surfactant to display different efficiencies. Carboplatin was used as the model drug. The cellular uptake, cytotoxicity, and migration inhibition of quantiosomes for treating melanoma cells were described. Finally, intratumoral carboplatin accumulation and in-vivo bioimaging were examined.
Results The average diameters of quantiosomes ranged between 151 and 173 nm, depending on the composition selected. Approximately 50% of the drug was entrapped in quantiosomes. Electron microscopy confirmed the bilayer structure of quantiosomes and the presence of QDs in the vesicular surface. The nanodispersions showed a significant internalization into cells, especially the cationic formulations. Quantiosomes increased cytotoxicity against melanoma by 3 similar to 4-fold as compared to free carboplatin. In-vivo intratumoral administration demonstrated an increased drug depot in melanoma from 6 to 10 ng/mg by SPC-loaded and PEGylated quantiosomes relative to aqueous control. In-vivo fluorescence imaging showed that quantiosomes reduced leakage of QDs from melanoma. A fluorescence signal confined in tumors could be sustained for at least 24 h. Quantiosomes also exhibited a sensitive and prolonged fluorescence in ovarian tumors.
Conclusion Niosomes containing QDs and carboplatin as a multifunctional nanosystems provide a non-expensive and efficient strategy to prolong drug retention and fluorescence signal in tumors.