Supramolecular hydroxyapatite complexes as theranostic near-infrared luminescent drug carriers

The facile synthesis of luminescent, multifunctional, needle-like hydroxyapatite (HA) nanoparticle complexes containing cyclodextrin has been reported. The in vitro loading and release studies using doxorubicin hydrochloride (DOX) demonstrate that the nanoparticle complexes show high drug adsorption capacity and sustained drug release profiles. Moreover, they exhibit strong photoluminescence even after loading of DOX molecules and permit the monitoring of the photoluminescence intensity. The nanocomplexes further reveal excellent blood compatibility, inappreciable toxicity and cellular internalization properties. Upon excitation at 420 nm, these complexes exhibit strong near-infrared emission at 680 nm. The photoluminescence intensity of the nanoparticles can be adjusted by varying the concentration of neodymium. Thus, the nanoparticle complexes obtained in the present study are promising for applications in the biomedical field as multifunctional drug delivery systems for simultaneous targeted drug delivery and near-infrared fluorescence imaging guidance.