Functionalization with doxorubicin and trastuzumab of medium-entropy MgFeGdDy layered double hydroxides with magnetic resonance imaging contrast activity

Layered double hydroxides (LDH) with the MgAl and ZnAl cation combination are well-known as drug-delivery vehicles. Aluminum provides structural stability, enabling the intercalation and functionalization of materials to produce multifunctional materials for biomedical applications. However, aluminum is not desirable as it is a possible promoter of neurodegenerative diseases. In this work, we explore some procedures to obtain aluminum-free LDHs composed of MgFe, additionally including Gd(III) and Dy (III) cations. The resulting medium-entropy material was further functionalized with doxorubicin (Dox), a chemotherapeutic drug, and trastuzumab (Tzmb), an antibody used to confer selectivity to breast cancer cells. The stability of the medium-entropy structure was assessed against the functionalization processes by X-ray diffraction (XRD), infrared spectroscopy (FTIR), and the Z-potential technique. Finally, the functionalized particles were active as magnetic resonance imaging (MRI) contrast agents, proving the potential use of the MgFeGdDy LDH as theragnostic particles.