Detection and identification of proteins using nanoparticle-fluorescent polymer 'chemical nose' sensors.

A sensor array containing six non-covalent gold nanoparticle-fluorescent polymer conjugates has been created to detect, identify and quantify protein targets. The polymer fluorescence is quenched by gold nanoparticles; the presence of proteins disrupts the nanoparticle-polymer interaction, producing distinct fluorescence response patterns. These patterns are highly repeatable and are characteristic for individual proteins at nanomolar concentrations, and can be quantitatively differentiated by linear discriminant analysis (LDA).

Sequence-specific Methyltransferase-Induced Labelling (SMILing) of plasmid DNA for studying cell transfection.

Plasmid DNA (pUC19 and pBR322) was sequence-specifically, covalently labelled with Cy3 fluorophores using a newly synthesised N-adenosylaziridine cofactor and the DNA methyltransferase M.TaqI. The fluorescently labelled plasmids were used for transfection of mammalian cells and their intracellular distribution was visualised by epifluorescence and confocal fluorescence microscopy.

Stabilization of α-chymotrypsin at air-water interface through surface binding to gold nanoparticle scaffolds.

Gold nanoparticles stabilize chymotrypsin (ChT) against denaturation at the air-water interface through catenation and preferential localization of the nanoparticles at the air-water interface with concomitant decrease in interfacial energy.