Using Alendronic Acid Coupled Fluorescently Labelled SM Liposomes as a Vehicle for Bone Targeting

Background: We have recently developed a liposomal nanoparticle system that can be used for drug delivery and simultaneously be monitored by optical or photoacoustic imaging devices. Here we tested the efficacy of alendronate as a homing molecule in SM-liposomes for bone targeting.

Methods: Alendronate was immobilized covalently on the liposomal surface and the fluorescent dye indocyanine green was used as a payload in the liposomes. The indocyanine green delivery was analyzed by 3D optical tomography, optical fluorescence scanner, photoacoustic imaging, and by exvivo biodistribution studies.

Results: The results show that the alendronate coupled to the liposomal surface increases Sphingomyelin containing liposome targeting up to several fold.

Conclusion: The alendronate targeted liposomes open possibilities for an application in active bone targeting.