Impact of particulate antigens, such as Bacillus anthracis, on the uniformity of response across a biosensor flow cell as determined by GC-SPR.

Biosensors are desired for the detection of a wide range of analytes in various scenarios, for example environmental monitoring for biological threats, from toxins to viruses and bacteria. Ideally a single sensor will be capable of simultaneous multianalyte detection. The varying nature, and in particular disparate size, of such a variety of analytes poses a significant challenge in the development of effective high-confidence instruments. Many existing biosensors employ functionalized flow cells in which spatially defined arrays of surface-immobilized recognition elements, such as antibodies, specifically capture their analyte of interest. To function optimally, arrays should provide equivalent responses for equivalent events across their active area. Experimental data obtained using a grating coupled surface plasmon resonance (GC-SPR) instrument, the BIAcore Flexchip, have revealed differences in response behaviors between proteinaceous and particulate analytes. In particular, the magnitude of responses seen with Bacillus anthracis spores appears to be influenced by shear and gravitational effects while those from soluble proteins are more uniform. We have explored this dependence to understand its fundamental impact on the successful implementation of multianalyte environmental biological detection systems.

Concurrent numerical simulation of flow and blood clotting using the lattice Boltzmann technique.

In this paper, we describe a novel approach for a concurrent numerical simulation of the unsteady flow within an idealised stenosed artery and a simplified blood clotting process based on a residence time model. The applied numerical scheme is the lattice Boltzmann technique, which proved to be highly efficient particularly for transient flows and complex or varying geometries.