Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : A nanoporous interferometric micro-sensor for biomedical detection of volatile sulphur compounds | Kumeria et al. Nanoscale Research Letters 2011 6 634 http content 6 1 634 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access A nanoporous interferometric micro-sensor for biomedical detection of volatile sulphur compounds Tushar Kumeria Luke Parkinson and Dusan Losic Abstract This work presents the use of nanoporous anodic aluminium oxide AAO for reflective interferometric sensing of volatile sulphur compounds and hydrogen sulphide H2S gas. Detection is based on changes of the interference signal from AAO porous layer as a result of specific adsorption of gas molecules with sulphur functional groups on a gold-coated surface. A nanoporous AAO sensing platform with optimised pore diameters 30 nm and length 4 pm was fabricated using a two-step anodization process in M oxalic followed by coating with a thin gold film 8 nm . The AAO is assembled in a specially designed microfluidic chip supported with a miniature fibre optic system that is able to measure changes of reflective interference signal Fabry-Perrot fringes . When the sensor is exposed to a small concentration of H2S gas the interference signal showed a concentration-dependent wavelength shifting of the Fabry-Perot interference fringe spectrum as a result of the adsorption of H2S molecules on the Au surface and changes in the refractive index of the AAO. A practical biomedical application of reflectometric interference spectroscopy RIfS Au-AAO sensor for malodour measurement was successfully shown. The RIfS method based on a nanoporous AAO platform is simple easy to miniaturise inexpensive and has great potential for development of gas sensing devices for a range of medical and environmental applications. Keywords nanoporous alumina reflectometric interference spectroscopy volatile sulphur compounds hydrogen sulphide sensor oral malodour Introduction Hydrogen sulphide H2S is a colourless corrosive flammable and highly toxic gas commonly known through its .
