Abstract: In recent times there has been a growing interest in the
development of quasi-two-dimensional niobium pentoxide (Nb2O5)
as a semiconductor for the potential electronic applications such as
capacitors, filtration, dye-sensitised solar cells and gas sensing
platforms. Therefore once the purpose is established, Nb2O5 can be
prepared in a number of nano- and sub-micron-structural
morphologies that include rods, wires, belts and tubes. In this study
films of Nb2O5 were prepared on gold plated silicon substrate using
spin-coating technique and subsequently by mechanical exfoliation.
The reason this method was employed was to achieve layers of less
than 15nm in thickness. The sintering temperature of the specimen
was 800oC. The morphology and structural characteristics of the
films were analyzed by Atomic Force Microscopy (AFM), Raman
Spectroscopy, X-ray Photoelectron Spectroscopy (XPS).
Abstract: We present a label-free biosensor based on
electrochemical impedance spectroscopy for the detection of proinflammatory
cytokine Tumor Necrosis Factor (TNF-α). Secretion of
TNF-α has been correlated to the onset of various diseases including
rheumatoid arthritis, Crohn-s disease etc. Gold electrodes were
patterned on a silicon substrate and self assembled monolayer of
dithiobis-succinimidyl propionate was used to develop the biosensor
which achieved a detection limit of ~57fM. A linear relationship was
also observed between increasing TNF-α concentrations and chargetransfer
resistance within a dynamic range of 1pg/ml – 1ng/ml.