Description:
<jats:title>Abstract</jats:title>
<jats:p>Gold nanoparticles (AuNPs) are considered to be ideal drug delivery vehicles for chemotherapeutic molecules due to the bio-inert nature of the colloids. Critical factors which determine the cellular internalization and intracellular localization of AuNPs are nanoparticle size as well as surface charge. Polydisperse AuNPs with a cationic surface charge, rich in primary amines would present multiple covalent molecule attachment loci and would be ideal for the delivery of chemotherapeutics which have multiple intracellular sites of action. In an adapted synthesis method, polydisperse cationic AuNPs were produced which were soluble in aqueous solution and showed high chemical stability. The synthesis was conducted in a comparative manner using polyethyleneimine (PEI) and reduced glutathione (GSH) as AuNP surface passivation ligands. Anisotropic as well as spherical morphologies were observed for the PEI passivated AuNPs, where the morphology was dependent on the ratio of reducing agent to Au<jats:sup>3+</jats:sup> in solution. Only spherical morphologies were observed when GSH was used as the passivation ligand under similar conditions. The surface chemistry of the AuNPs was characterized by means of attenuated total reflectance spectroscopy and elemental composition was determined using energy dispersive X-ray spectroscopy. The PEI AuNPs surface was nitrogen rich, cationic and provided multiple covalent primary amine attachment points for downstream surface tailoring.</jats:p>