Design, synthesis and evaluation of RGD peptidomimetic – Gold nanostar conjugates as M21 cell adhesion inhibitors

[Display omitted] •Star-shaped particles (AuNSts) possess high surface-to-volume ratio useful for improving drug loading efficiency.•AuNSts surface plasmon resonance in the “NIR transparent window” is a key aspect for in vivo therapeutic purposes.•The covalent conjugation of pegylated AuNSts with a small molecule triazole RGD-peptidomimetic is reported.•RGD-AuNSTs nanoconstructs show a multivalent effect in binding αvβ3 and inhibit M21 cell adhesion at pM conc. Effective targeting of αvβ3 integrin is of high relevance in cancer research as this protein is overexpressed on several types of tumor cells, making such receptor ideal for the development of therapeutics and of diagnostic imaging agents. In this paper, the synthesis of a novel functionalized triazole-based RGD peptidomimetic and its covalent conjugation on pegylated gold nanostars is reported. These highly stable nanoconstructs showed a multivalent effect in binding αvβ3 integrin receptors and proved to inhibit M21 cell adhesion at 25 pM concentration. Thanks to their peculiar surface plasmon resonance in the “NIR transparent window”, targeted gold nanostars may represent a promising agent for anticancer multi-modality treatments. 2009 Elsevier Ltd. All rights reserved.