Development of an immunoassay to measure progesterone using printed biosensors, and its application to the assessment of ovarian function in the numbat (Myrmecobius fasciatus).

A biosensor system was developed to measure progesterone levels in the urine of female numbats (Myrmecobius fasciata) as an index of ovarian function. Screen printed sensors were coated with a monoclonal progesterone antibody, and incubated in a mixture of sample/standard and progesterone-3-CMO-horseradish peroxidase (HRP). The difference in potential between the working and reference electrode was measured, after exposure to an HRP substrate. EIA and biosensor standard curves showed parallelism, and the biosensor gave values similar (r = 0.83) to the conventional EIA. Progesterone concentrations at different stages of the oestrus cycle were not significantly different to those obtained by EIA.

The concentration of iron in real-world geogenic PM10 is associated with increased inflammation and deficits in lung function in mice.

BACKGROUND: There are many communities around the world that are exposed to high levels of particulate matter <10 µm (PM10) of geogenic (earth derived) origin. Mineral dusts in the occupational setting are associated with poor lung health, however very little is known about the impact of heterogeneous community derived particles. We have preliminary evidence to suggest that the concentration of iron (Fe) may be associated with the lung inflammatory response to geogenic PM10. We aimed to determine which physico-chemical characteristics of community sampled geogenic PM10 are associated with adverse lung responses. METHODS: We collected geogenic PM10 from four towns in the arid regions of Western Australia. Adult female BALB/c mice were exposed to 100 µg of particles and assessed for inflammatory and lung function responses 6 hours, 24 hours and 7 days post-exposure. We assessed the physico-chemical characteristics of the particles and correlated these with lung outcomes in the mice using principal components analysis and multivariate linear regression. RESULTS: Geogenic particles induced an acute inflammatory response that peaked 6 hours post-exposure and a deficit in lung mechanics 7 days post-exposure. This deficit in lung mechanics was positively associated with the concentration of Fe and particle size variability and inversely associated with the concentration of Si. CONCLUSIONS: The lung response to geogenic PM10 is complex and highly dependent on the physico-chemical characteristics of the particles. In particular, the concentration of Fe in the particles may be a key indicator of the potential population health consequences for inhaling geogenic PM10.