Self-assembled platinum nanochains based on octreotide acetate

Biological scaffolds are used for the synthesis of inorganic materials due to their ability to self-assemble and nucleate crystal formation. We reported a facile method for preparing self-assembled Pt nanochains by using octreotide acetate (AOC) as bio-template in aqueous environment. The influence of solution pH was examined to define the optimal conditions for the formation of the AOC bio-templated Pt nanoparticles (PtNPs) arrays, the AOC has diameter about 55 nm at pH 2.0, for comparison, at pH 9.0, the diameter of AOC is about 25 nm. After 24-h incubation of AOC (pH 2.0) with PtCl4 and chemical reduction with borane-dimethyl-amine, uniform platinum nanoparticles (mean diameter 2.5 ± 0.5 nm) directed by AOC were formed. Preliminary characterizations of the synthesized PtNPs were performed using transmission electron microscopy, high-resolution transmission electron microscopy, energy dispersive spectroscopy, and selected area of electron diffraction. The cytotoxicity of Pt/octreotide acetate complexes (PtNPs–AOC) and AOC was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The results indicated that the antiproliferative effect of PtNPs–AOC is as high as AOC. In addition, the nano-design architecture of the Pt particles plays a crucial role in a strong enhancement of the biological efficiency of radiations, making PtNPs–AOC a promising material for anticancer drug delivery in the future.