Authors: K. Rahme, J.D. Holmes
Affilation: Notre Dame University (Louaize), Lebanon
Pages: 147 - 150
Keywords: gold nanoparticles, hydroxylamine-o-sulfonic acid, polyethylene glycol (PEG), protein, bioconjugation
Gold nanoparticles (Au NPs), with diameters ranging between 60-150 nm, have been synthesised in water at room temperature by reducing HAuCl4.3H2O with hydroxylamine-o-sulfonic acid in the presence of sodium citrate, as stabilising agent. 15 and 30 nm Au NPs were obtained using sodium citrate as both the reducing and stabilising agent at high temperature (Au-citrate NPs), in the absence of hydroxylamine-o-sulfonic acid (Turkevich and Frens method). Functionalised polyethylene glycol-based thiol polymers were used to stabilise the pre-synthesised Au NPs. The obtained nanoparticles were characterised using uv-visible spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM). Further biocojuguation on 15, 30 and 80 nm PEGylated Au NPs were performed by grafting Bovine Serum Albumin, Transferrin and Apolipoprotein E (ApoE). Since, direct synthesis of Au NPs by the Turkevish method does not yield large diameter Au nanoparticles, that can typically be synthesised using a seeding growth method.Our method for synthesising Au NPs between 60 and 150 is an extension of the approaches described by Turkevich, Frens and others to produce Au NPs with diameter below 40 nm.Bioconjugation of the obtained Au NPs with proteins make them very attractive for further applications in biology (in progress).