The objective of this research was to develop new technology for possible noncontact, nondestructive, and culture-independent rapid detection of Salmonella using ferromagnetic nanoparticles. Light signal changes of particles, cells, and their reaction stages were investigated. Amino-functionalized ferromagnetic nanoparticles (amino-FMNs) were synthesized and modified by glutaraldehyde to crosslink the attachment of specific antibodies to the particles. The nanoparticle complex was used to capture, concentrate, and isolate Salmonella in a culture broth. Signal changes of the four stages of the nanoparticles-amino-glutaraldehyde-antibodies-Salmonella cell attachments were tracked with sensitive Synchrotron FTIR spectroscopy (SR-FTIR). The unique peaks from these four steps were identified. Results can be applied to develop a new test method or a new test/universal reader for rapid, nondestructive, and culture-independent detection of Salmonella in food products using IR spectroscopy at wave numbers 1454 cm-1, 1542 cm-1, and 1414 cm-1, respectively.

Functionalized DNA sequences are promising sensing elements to combine with transducers for bio-sensing specific target microbes. As an application example, this paper demonstrates in situ detection of loop-mediated isothermal amplification products by hybridizing them with thiolated-ssDNA covalently anchored on the electrodes of a quartz crystal microbalance (QCM). Such hybridization leads to a frequency signal, which is suitable for monitoring real-time LAMP amplification based on mass-sensing: it detects interactions between the complementary nucleobases of LAMP products in solution and the thiolated-ssDNA probe sequence on the gold surface. Target DNA LAMP products cause irreversible frequency shifts on the QCM surfaces during hybridization in the kHz range, which result from both changes in mass and charge on the electrode surface. In order to confirm the LAMP assay working in the QCM sensing system at elevated temperature, the sky blue of positive LAMP products solution was achieved by using the Hydroxy Naphthol Blue (HNB) and agarose gel electrophoresis. Since on-QCM sensing of DNA hybridization leads to irreversible sensor responses, this work shows characterization by X-ray photoelectron spectroscopy (XPS) core spectra of S2p, N1s, Mg1s, P2p and C1s. XPS results confirmed that indeed both DNA and by-products of LAMP attached to the surface. Listeria monocytogenes DNA served to study in-situ detection of amplified LAMP products on DNA-functionalized surfaces.

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Soil is the most basic of all resources; it is the essence of all terrestrial life and a cultural heritage (Bini & Zilioli, 2013). Soil is a non-renewable resource therefore it is vital to know the complex interactions between processes, factors and causes occurring at a range of spatial and temporal scale (Lal, 2015). Soils are characterized by a high degree of spatial variability because of the combined effects of physical, chemical, and biological processes that operate with different intensities and at different scales (Awal et al., 2019) and depending on differences in genetic and Abstract: Soil properties intricately vary spatially owing to several natural and anthropogenic factors including parent material, terrain as well as land use. The aim of this study is to assess the spatial variability of soil samples collected from three different land use types namely: reserved area, parkland and farmland around Baturiya Sanctuary, northwestern Nigeria with a view to providing information that will assist the government in planning and conservation of the area. Free traverse sampling technique was used to collect soil samples at the depth of 0-30cm. Laboratory analysis was done for the following parameters: bulk density, PSD, phosphorous, pH, EC, total nitrogen, exchangeable bases (Mg, Na, and K), and CEC. Geostatistical technique (semivariogram analysis) was used to test variation in soil properties. Result of the study depicted that It also indicated that BD (1.24 g/cm3), clay (22%), total nitrogen (0.25 g/kg), available phosphorous (32.61 mg/g), OC (1.6%) and Mg (0.05) are highest in reserved area. Also sand (55%) and silt (29%), pH (5.0), EC (522), Na (0.007), K (0.44) and CEC (4.5meq/100g) are highest in farmland. The variogram based nugget-sill ratio showed strong dependency with 0 (N, EC, OC) and weak dependency 1 (BD, Na) on the scale of 0.25 high, 0.25-0.75 moderate and 0.75 weak. In conclusion, this study found that soil properties in area showed high to moderate spatial dependency except for BD, Mg, K, and Na which showed low spatial autocorrelation owing increasing human activities in the area. This study depicted that apparently limitation by few samples have influenced the pattern in the result otherwise spatial variability of certain elements may be more discernible and beyond reasons such land use and parent materials.