This study reports methods for coating miniature implantable glucose biosensors with electrospun polyurethane (PU) membranes, their effects on sensor function and efficacy as mass-transport limiting membranes. For electrospinning fibres directly on sensor surface, both static and dynamic collector systems, were designed and tested. Optimum collector configurations were first ascertained by FEA modelling. Both static and dynamic collectors allowed complete covering of sensors, but it was the dynamic collector that produced uniform fibro-porous PU coatings around miniature ellipsoid biosensors. The coatings had random fibre orientation and their uniform thickness increased linearly with increasing electrospinning time. The effects of coatings having an even spread of submicron fibre diameters and sub-100μm thicknesses on glucose biosensor function were investigated. Increasing thickness and fibre diameters caused a statistically insignificant decrease in sensor sensitivity for the tested electrospun coatings. The sensors’ linearity for the glucose detection range of 2 to 30mM remained unaffected. The electrospun coatings also functioned as mass-transport limiting membranes by significantly increasing the linearity, replacing traditional epoxy-PU outer coating. To conclude, electrospun coatings, having controllable fibro-porous structure and thicknesses, on miniature ellipsoid glucose biosensors were demonstrated to have minimal effect on pre-implantation sensitivity and also to have mass-transport limiting ability.

This report, prepared for the Community Planning Study -Snowmass 2013 -summarizes the theoretical motivations and the experimental efforts to search for baryon number violation, focussing on nucleon decay and neutron-antineutron oscillations. Present and future nucleon decay search experiments using large underground detectors, as well as planned neutron-antineutron oscillation search experiments with free neutron beams are highlighted. OverviewBaryon Number, B, is observed to be an extremely good symmetry of Nature. The stability of ordinary matter is attributed to the conservation of baryon number. The proton and the neutron are assigned B = +1, while their antiparticles have B = −1, and the leptons and antileptons all have B = 0. The proton, being the lightest of particles carrying a non-zero B, would then be absolutely stable if B is an exactly conserved quantum number. Hermann Weyl formulated the principle of conservation of baryon number in 1929 primarily to explain the stability of matter [1]. Weyl's suggestion was further elaborated by Stueckelberg [2] and Wigner [3] over the course of the next two decades. The absolute stability of matter, and the exact conservation of B, however, have been questioned both on theoretical and experimental grounds. Unlike the stability of the electron which is on a firm footing as a result of electric charge conservation

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This paper presents time-resolved adsorption behavior of lysozyme, bovine serum albumin (BSA), and immunogamma globulin (IgG) onto a liquid crystal phthalocyanine surface and concentrates on the kinetic, viscoelastic variation, interfacial hydration, and structural details obtained by quartz crystal microbalance dissipating monitoring (QCM-D) technique with the Voigt model. The rate of adsorption for lysozyme is faster than that of BSA and IgG. The Freundlich model can explain the adsorption isotherm of lysozyme, whereas an exponential growth model can describe that of BSA and IgG. Layer surface coverage has been found to increase for all three proteins with significant variation in surface packing density and viscoelastic parameters within the investigated concentration range. The adsorbed IgG and BSA form soft, water-rich multilayers with large energy dissipation. The layer viscosity and shear modulus have been found to decrease as the protein hydration increases with concentration in these cases. On the other hand, lysozyme forms a rigid, negligibly hydrated multilayer with higher values of viscosity, shear modulus. Among three proteins, IgG is found to be a good adsorbent for liquid crystal surface comparing their theoretical monolayer surface coverage.