Cancer-targeting siRNA delivery from porous silicon nanoparticles.

Aims: Porous silicon nanoparticles (pSiNPs) with tunable pore size are biocompatible and biodegradable, suggesting that they are suitable biomaterials as vehicles for drug delivery. Loading of small interfering RNA (siRNA) into the pores of pSiNPs can protect siRNA from degradation as well as improve the cellular uptake. We aimed to deliver MRP1 siRNA loaded into pSiNPs to glioblastoma cells, and to demonstrate downregulation of MRP1 at the mRNA and protein levels.

Nanoporous alumina-based interferometric transducers ennobled.

A high fidelity interferometric transducer is designed based on platinum-coated nanoporous alumina films. The ultrathin metal coating significantly improves fidelity of the interferometric fringe patterns in aqueous solution and increases the signal-to-noise ratio. The performance of this transducer is tested with respect to refractive index unit (RIU) sensitivity measured as a change in effective optical thickness (EOT) in response to a solvent change and compared to porous silicon based transducers.

Porous silicon biosensors on the advance.

Biosensor research is a rapidly expanding field with an immense market potential spanning a broad spectrum of applications including biomedical diagnostics, environmental monitoring, veterinary and food quality control. Porous silicon (pSi) is a nanostructured material poised to take centre stage in the biosensor development effort. This can be ascribed to the ease and speed of fabrication, remarkable optical and morphological properties of the material (including tuneable pore size and porosity), large internal surface area and the versatile surface chemistry.

Self-assembly of electro-active protein architectures on electrodes for the construction of biomimetic signal chains.

The layer-by-layer adsorption technique based on the consecutive deposition of oppositely charged species is suitable for the preparation of protein multilayers with fully electro-active protein molecules. The methodology was established with cytochrome c and the polyelectrolyte sulfonated polyaniline (PASA). The technique is also useful for the construction of bi-protein architectures confining protein-protein communication to an electrode.

Electrocatalytic sulfite biosensor with human sulfite oxidase co-immobilized with cytochrome c in a polyelectrolyte-containing multilayer.

An efficient electrocatalytic biosensor for sulfite detection was developed by co-immobilizing sulfite oxidase and cytochrome c with polyaniline sulfonic acid in a layer-by-layer assembly. QCM, UV-Vis spectroscopy and cyclic voltammetry revealed increasing loading of electrochemically active protein with the formation of multilayers. The sensor operates reagentless at low working potential.