New paper in ACS Applied Materials & Interfaces

Roshan and colleagues have recently published in ACS Applied Materials & Interfaces their work demonstrating microwave-induced heating of gold nanoparticles and nanorods.

Illustration of the μ-wave controlled Con A display on GNP. In the absence of the μ-waves, the expanded polymer prevents the interaction of the Con A with a methyl-α-d-mannopyranoside-functionalized electrode. Upon irradiation with μ-waves, the GNP heat up and cause the collapse of the PNIPAM layer, resulting in exposure of the Con A and binding to the electrode surface.

An appreciably higher and concentration-dependent microwave-induced heating rate was observed with aqueous dispersions of the nanomaterials as opposed to pure water and other controls. Grafted with the thermoresponsive polymer poly(N-isopropylacrylamide), these gold nanomaterials react to microwave-induced heating with a conformational change in the polymer shell, leading to particle aggregation. They subsequently covalently immobilize concanavalin A (Con A) on the thermoresponsive gold nanoparticles. Con A is a bioreceptor commonly used in bacterial sensors because of its affinity for carbohydrates on bacterial cell surfaces. The microwave-induced thermal transitions of the polymer reversibly switch on and off the display of Con A on the particle surface and hence the interactions of the nanomaterials with carbohydrate-functionalized surfaces. This effect was determined using linear sweep voltammetry on a methyl-α-d-mannopyranoside-functionalized electrode.

You can find out more in: ACS Applied Materials & Interfaces, 7 (2015) 27755-27764