Characterization of biomolecular nanoconjugates by high-throughput delivery and spectroscopic difference

Abstract

Aim: Nanoparticle conjugates have the potential for delivering siRNA, splice-shifting oligomers or nucleic acid vaccines, and can be applicable to anticancer therapeutics. This article compares tripartite conjugates with gold nanoparticles or synthetic methoxypoly(ethylene glycol)-block-polyamidoamine dendrimers. Materials & methods: Interactions with model liposomes of a 1:1 molar ratio of tripalmitin:cholesterol or phospholipid:cholesterol were investigated by high-throughput absorbance, as well as fluorescence difference and cellular luminescence assays. Results: Spectral differences and dynamic light-scattering spectroscopy shifts demonstrated the interaction of conjugates with liposomes. Biological activity was demonstrated by upregulation of gene expression via splice-shifting oligomers, delivery of anti-B-Raf siRNA in cultured human cancer cells or tuberculosis antigen 85B plasmid expression vector in a coculture model of antigen presentation. Conclusion: The data suggests that gold nanoparticles and methoxypoly(ethylene glycol)-block-polyamidoamine dendrimer nanoconjugates may have potential for binding, stabilization and delivery of splice-shifting oligomers, siRNA and nucleic acid vaccines for preclinical trials. Original submitted 19 December 2011; Revised submitted 3 April 2012; Published online 3 September 2012