Silver nanostructures have been always a material of attraction due to its outstanding electrical and optical features. Here, silver nanorods (AgNRs) array fabricated on glass substrates by electron beam dynamic angle deposition, has been employed in biosensing applications. The average length and diameter of the nanorods were determined to be 900 nm and 100 nm respectively by electron microscopy. The colorimetric and water wetting properties of as-fabricated AgNRs arrays were found to be highly sensitive towards the sulfurization. In the presence of H2S gas, the as-fabricated whitish AgNRs array turns black (due to formation of black Ag2S). In addition, it also changes its water wetting property from hydrophobic (water contact angle CA=128°) to hydrophilic (CA=65°). The coproduct of the reaction; OH- ions on the AgNRs surface may found to attribute to enhance the wettability. The dual mode rapid and selective detection of H2S gas was demonstrated by using a house-made android based mobile app “Colorimetric Detector”. The performance of the sensor was investigated by its sensing ability of 5 ppm of gas with exposure time of only 30 seconds.

The Magneto-photonic crystals/MPCs are promising candidates for devising high-fidelity embedded biosensor systems which offer facile & real time detection of diagnostic proteins. Despite extensive use of magnetic nanomaterials for theranostic applications, the idea of exploiting its photonic response when assembled as a colloid inside a matrix remains unexplored. Herein, we report a novel label free method for quantitative detection of interleukin 6 which is a widely used prognostic marker for multiple pathological conditions. Cobalt ferrite/CoF and magnetite nanoparticles with Ms of 74.8 and 77 emu g⁻¹ were assembled inside a hydrogel matrix with the application of an external magnetic field. Through the use of click chemistry, detecting antibodies were immobilized on their surface. The interaction of interleukin 6 with the antibodies produces a blue- shift in resonant wavelength and the reflectance intensity increases up to 50% and 44% when tested with CoF & magnetite based MPC respectively at a concentration of 50 pg ml⁻¹. The dynamic range of the sensor lies within the prognostic values of IL-6, and the integrated sensing mechanism proposed in this  study provides an ideal platform for real-time management of sepsis in patients with higher degree burns.

Ana Domingues has completed his Mater at the age of 23 years from University of Minho (Portugal), in Erasmus context in University of Freiburg (Germany). She worked almost one and half years as Biomedical Engineer. Currently, she is Project Engineer at Active Space Tecnologies in Coimbra, Portugal.