Fabrication of integrated microanalytical chambers and channels for biological assays using flame hydrolysis deposition glass

The aim of this study was to develop and optimise a process to etch deep, high aspect ratio microstructures in glasses. To this end, we examined the use of flame hydrolysis deposition (FHD) to form integrated lab-on-a-chip structures involving silica-on-silicon. The FHD process allows buried optical waveguide structures to be produced, which are isolated from the surface using a glass overlayer, or cladding. This arrangement allows sensing regions, such as microanalytical chambers and capillary channels for microfluidics, to be defined by etching through the upper cladding. In this paper we also demonstrate a simple fluorescence assay measurement, to illustrate the potential application of this technology.