Engineering lanthanide-based materials for nanomedicine

Multifunctional lanthanide-based nanomaterials are envisioned to create a huge impact in nanomedicine through improved diagnosis and treatment of diseases. This review focuses on the opportunities and advantages afforded by "designer" lanthanide-based nanomaterials in medical application in the recent 5 years. We begin with a brief overview of the unique properties of lanthanide nanomaterials and then move onto their synthesis, surface modification and bioconjugation strategies, which help one in the design of promising agents for imaging and therapeutic applications. We discuss approaches to fabricate down-conversion, up-conversion and persistent luminescent probes for optical imaging. We present the recent development of lanthanide-based nanoprobes in T-1 and T-2 magnetic resonance imaging, which show superior performances over currently used commercials agents. The potential benefits of multifunctional lanthanide-based nanomaterials in multimodal diagnostics are also highlighted. An important feature of lanthanide-based nanomaterials is the external controllability of light emission from UV to NIR wavelengths. This unique capability makes this class of nanomaterials useful for not only controlled/triggered release of drugs and gene delivery but also photodynamic or photothermal therapy at targeted sites. Finally, we discuss recent efforts to address concerns of short-term and long-term toxicity of lanthanide materials. The wide range of unique features of lanthanide-based nanomaterials accentuates their promise as efficient platforms for nanomedicine. (C) 2014 Elsevier B.V. All rights reserved.