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Uniform sized Ni-Co alloy nanoparticles were effectively confined over the active channels of mesoporous silica nanoparticles (MSN) using a simple chemical reduction method, and the resultant nanostructures exhibited a spherical configuration with a mean diameter of 5 nm. The face-centered cubic (fcc) crystalline structure of Ni and Ni-Co alloy nanoparticles and the amorphous structure of MSN matrix were identified from the diffraction patterns. The MSN supported catalysts were exploited as electrochemical probes for the detection of glucose, and the controlled morphology, smaller particle size, uniform dispersion and active surface of the Ni-Co alloy nanoparticles improved the excellent electrocatalytic activity of MSN/Ni-Co toward the electrooxidation of glucose. The MSN/Ni-Co nanocomposite exhibited good analytical performance for glucose detection, with a linear response ranging from 0.001 to 5.0 mM, a low detection limit of 0.39 mM and a high sensitivity of 536.62 mA mM À1 cm À2 . The results of the performed experiments also demonstrated the good reproducibility, long-term stability and high selectivity of the fabricated sensors without the influence of interference from other oxidizable species, which may represent a technically sound and economical new avenue in nonenzymatic glucose sensor applications.

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Phenotypic and genotypic changes in Aspergillus niger and Penicillium chrysogenum, spore forming filamentous fungi, with respect to central chitin metabolism were studied under low shear modeled microgravity, normal gravity and static conditions. Low shear modeled microgravity (LSMMG) response showed a similar spore germination rate with normal gravity and static conditions. Interestingly, high ratio of multiple germ tube formation of A. niger in LSMMG condition was observed. Confocal laser scanning microscopy images of calcofluor flurophore stained A. niger and P. chrysogenum showed no significant variations between different conditions tested. Transmission electron microscopy images revealed number of mitochondria increased in P. chrysogenum in low shear modeled microgravity condition but no stress related-woronin bodies in fungal hyphae were observed. To gain additional insight into the cell wall integrity under different conditions, transcription level of a key gene involved in cell wall integrity gfaA, encoding the glutamine: fructose-6-phosphate amidotransferase enzyme, was evaluated using qRT-PCR. The transcription level showed no variation among different conditions. Overall, the results collectively indicate that the LSMMG has shown no significant stress on spore germination, mycelial growth, cell wall integrity of potentially pathogenic fungi, A. niger and P. chrysogenum.

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