A facile synthesis of size- and shape-controlled Gd(OH)3 nanoparticles and Gd(OH)3@Au core/shell nanostars

Abstract

Nanoparticles (NPs) have provided new opportunities to diagnose and treat various types of cancers, while it still remains a great challenge to develop novel and effective nanoscale platforms for these applications. In this study, we report a facile hydrothermal route to generate size- and shape-controlled gadolinium hydroxide (Gd(OH)₃) NPs and polyethylenimine (PEI)-stabilized Gd(OH)₃@Au core/shell nanostars (NSs). We show that Gd(OH)₃ NPs with controlled size and shape can be synthesized through varying the stabilizer, reaction time and solvent. The formed Gd(OH)₃ nanorods can be transformed into rice-shaped counterparts in the presence of trisodium citrate dehydrate. Furthermore, the introduction of PEI does not alter the morphology, rather have an impact on the size of the products. This facile synthetic route can also be utilized to synthesize Gd(OH)₃@Au nanocomposite particles that can act as seeds to form Gd(OH)₃@Au NSs in the Au growth solution. Further modification of PEI endows these NSs with excellent water-solubility and colloidal stability. Due to the strong surface plasmon resonance peak in the near-infrared region, the as-prepared Gd(OH)₃@Au-PEI NSs display a high photothermal conversion efficiency under laser irradiation. The developed size- and shape-controlled Gd(OH)₃ NPs and PEI-stabilized Gd(OH)₃@Au core/shell NSs may be further developed as theranostic agents for various biomedical applications.