THE EFFECT OF POLYETHYLENE GLYCOL (PEG) COATING ON THE MAGNETO-STRUCTURAL PROPERTIES AND COLLOIDAL STABILITY OF Co0.8Mg0.2Fe2O4 NANOPARTICLES FOR POTENTIAL BIOMEDICAL APPLICATIONS

The effect of polyethylene glycol (PEG) coating on the magneto-structural properties and colloidal stability of Co0.8Mg0.2Fe2O4 magnetic nanoparticles (MNPs) was studied with their potential biomedical applications in mind using powder X-ray diffraction (XRD,Field Emission Scanning Electron Microscope (FESEM), vibrating sample magnetometer (VSM) and zeta potential measurements. Co0.8Mg0.2Fe2 MNPs were synthesized by a twostep chemical method including solution combustion synthesis followed by functionalisation with PEG. The XRD patterns indicate that the crystalline single phase cubic spinel structure was retained after PEG coating. Also, after PEG coating, the crystallite size (from Scherrer formula) increases from 50 to 56 nm. Magnetic measurements of both coated and uncoated particles reveal the ferrimagnetic nature at room temperature with the PEG coated sample recording a higher magnetic moment. The resulting PEG coated particles form a more stable suspension in aqueous environment and also an appreciable stability in phosphate buffer solution (PBS) at physiological pH. The higher magnetization and colloidal stability recorded with PEG coatings is an important parameter in biomedical applications

Solutions of the Schrödinger equation with inversely quadratic Hellmann plus inversely quadratic potential using Nikiforov-Uvarov method

By using the Nikiforov-Uvarov (NU) method, the Schrödinger equation has been solved for the interaction of inversely quadratic Hellmann (IQHP) and inversely quadratic potential (IQP) for any angular momentum quantum number, l. The energy eigenvalues and their corresponding eigenfunctions have been obtained in terms of Laguerre polynomials. Special cases of the sum of these potentials have been considered and their energy eigenvalues also obtained

Evaluatig the diesel biodegradatin potentil of wild microfungi isolated from decaying wood in Nigeria

We evaluated the potentils of pure wild microfungi isolated from decaying wood in utiizing diesel as source of carbon/energy and monitoring of their physiological responses via OD and pH gradient flxes. The fungi diversity was obtained by conventinal enrichment culture methods. Pure cultures of tentatie fungal species namely: SC1, SC2, SC3, YI and Y2 were tested for their ability to utiize diesel oil as carbon and energy source. From the cultural, morphological and biochemical characterizatin and comparison with respect to the standard reference of fungi, the wild microfungi tentatiely named as SC1, SC2, SC3, YI and Y2 were seemingly the members of Penicillum, Aspergillus, Mucor, Candida and Cryptococcus species. The diesel dependent growth of the pure microfungi was assessed by monitoring the flxes in the pH and Optial density OD of the minimal media slurry for 288 hours. There were flctuatins in OD as well as pH values for the diffrent microfungi. The mean pH data 5.90 ± 0.01-7.01± 0.01 and the OD 0.349±0.001 -1.232 ± 0.002 were obtained. The ability of our fungal isolates to tolerate diesel and grow in it, suggests that the isolates can be employed as bioremediatin agent

PHYSICOCHEMICAL ANALYSIS, PHYTOCHEMICAL SCREENING AND ANTIMICROBIAL ACTIVITIES OF SOME VEGETABLE OILS FROM OGUN STATE, NIGERIA

The study was carried out to assess the physicochemical properties, phytochemical screening and antimicrobial activities of twenty five different edible vegetable oil samples collected from Ota, Ogun state in Nigeria for their domestic and commercial applications. The moisture contents (0.02 – 0.13%), acid values (0.46 – 1.73 mg KOH/g), saponification values (226.19 – 310.19 mg KOH/g), iodine values (0.06 – 1.17 mg I2/g) and the low pH values (0.0 – 2.49) generally make these vegetable oils to be more useful in industrial applications than consumed directly or indirectly as ingredients in food. The results of the phytochemical screening of these oil samples indicated the presence of terpenoids, deoxysugar, steroids and cardenolides. The microbial sensitivity tests showed that most of the vegetable oil samples exhibited no inhibitory power against candida, Klebsiella pneumonia, Escherichia coli but only sample 25 (soya bean oil) was sensitive to these three microbes and its inhibition of these microbes was concentration dependent. The mineral contents of these oils showed detectable levels of Zn (2.57 –21.43 ppm), Mn (0.12 – 0.98 ppm), Fe (2.21 – 97.41 ppm), Cu (0.49 – 61.70 ppm), Cd (0.42 – 0.74 ppm) and Pb (0.14 – 31.09 ppm) which were found to be above the WHO permissible limits for these metals in drinking water

Low�Temperature Solution�Combustion Synthesis and Magneto�Structural Characterization of Polycrystalline La1–xAgyMnO3 (y ≤ x) Manganites

Silver is known to be a highly mobile (low�soluble) component in Ag�doped perovskite mangan� ites and hence several non�perovskite phases can exist in silver doped manganite perovskites with most syn� thetic routes making its synthesis to be problematic. In search of soft synthesis route, the low temperature combustion synthesis and magneto�structural studies of polycrystalline La1 – xAgyMnO3 (y ≤ x) ceramic man� ganites using glycine as a fuel is reported. The sintered powders were characterized by X�Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X�ray (EDAX) analysis, Thermo Gravi�metric Analysis (TGA) and Vibrating Scanning Magnetometer (VSM) measurements. XRD patterns showed formation of mainly single rhombohedral perovskite phase for the La0.8Ag0.15MnO3 sample and an admixture of secondary phases with La0.8Ag0.1MnO3 and La0.8Ag0.2MnO3 samples. The distinct microstructure and higher magnetic properties observed for La0.8Ag0.15MnO3 sample compared to the other samples were dis�cussed based on the XRD results

Heavy Metal Assessment of Ground, Surface and Tap Water Samples in Lagos Metropolis Using Anodic Stripping Voltammetry

The levels of heavy metal contamination in surface, ground and tap waters collected in some part of Lagos metropolis were determined using Differential Pulse Anodic Stripping Voltammetry (DPASV). The samples were analysed for their contents of lead, copper and cadmium and were also compared with the WHO (2008) specified contaminant levels for drinking water. The results obtained showed that all the well water and borehole water samples investigated contain high concentration of these heavy metals. Lead and cadmium concentrations were found to be above the WHO maximum acceptable concentration (MAC). However, none of the samples had copper concentration above the WHO MAC for copper. On the whole samples analysed, only the sample collected from Odo-Iyaalaro stream, Ojota showed no pollution of lead. Other samples showed pollution of all of the metals analysed. In general, the results show an indication of pollution hazards given the toxicity of these metals and mostly when the water sources studied represent the major sources of water for the teeming populace. DPASV results of the samples investigated were found to be comparable with results of same samples obtained from independent work carried out by Atomic Absorption Spectroscopy

BASIC ANALYTICAL EXAMINATION OF SELECTED STREAMS AND THEIR WATER QUALITY IN ADO-EKITI (SOUTHWESTERN NIGERIA) AND ITS NEIGHBOURING VILLAGES.

Water samples were collected from ten (10) streams at different locations within Ado-Ekiti and its environ in Ekiti State, South Western Nigeria. The samples were evaluated for their physico-chemical properties. The samples under investigation has pH within the range 7.6 to 8.2; total hardness 8.0 mg/l to 196.0 mg/l; Calcium and Magnesium hardness 1.6 mg/l to 76.0 mg/l and 0.49 mg/l to 19.93 mg/l respectively; total solids 0.2 mg/l to 1.2 mg/l; total suspended and total dissolved solids 0.00 to 0.06 mg/l, 0.14 mg/l to 1.16 mg/l respectively; free carbondioxde 3.74 × 10-3 mg/l to 5.72 × 10-3 mg/l; phenolphthalein acidity 9.0 mg/l to 15.0 mg/l; conductivity 4.0 µScm-1 to 570 µScm-1. The metal analysis results from atomic absorption spectroscopy (AAS) are as follows: Sodium (2.7 mg/l to 60.1 mg/l), Potassium (4.0 mg/l to 52.0 mg/l), Zinc (0.80 mg/l to 1.51 mg/l), Calcium (1.60 mg/l to 76.0 mg/l), Iron and Lead were not detected in the sample considered

Structural, morphological and magnetic properties of La1−xNayMnO3 (y ≤ x) nanoparticles produced by the solution combustion method

The rapid solution combustion synthesis and characterization of sodium (Na)-substituted LaMnO3 phases at relatively low temperature using polyvinyl alcohol (PVA) as fuel were reported. The thermal decomposition process investigated by means of differential and thermal gravimetric analysis (TG–DTA) showed that the use of PVA as a fuel was satisfactory in the synthesis of the perovskite manganite compound. Structural study using X-ray diffraction showed that all the samples were single phasic without any detectable impurities within the measurement range. Also, the Na-substituted compounds crystallize with rhombohedral symmetry (space group R-3c, no. 167) with La0.80Na0.15MnO3 manganite sample giving the highest crystallinity. Microstructural features observed by field-emission scanning electron microscopy demonstrated that most of the grains were nearly spherical in shape with fairly uniform distribution and all the observed particles connect with each other. Energy-dispersive X-ray analyses confirm the homogeneity of the samples. Increase in magnetic moment was observed with the increase in sodium doping. Room-temperature vibrating sample magnetometer measurements showed that the samples were ferromagnetic with compositions y = 0.10, 0.15 and 0.20 showing relatively high magnetic moments of 33, 34 and 36 emu g−1, respectively

Synthesis, Characterisation and pH-Responsive Controlled Release Studies of 5- Fluorouracil Drug from Silica CoatedLao.1Sro.3Mn03Magnetic Nanoparticles

One of the drawbacks of some drug delivery system (DDS) is their inability to release their payloads after reaching the desired site of action. Hence, many DDSs are being evaluated that are able to release their payloads upon action of an external stimulus. La0.7SrO.JMn03 MNPs were synthesized by solution combustion synthesis and the optimised MNPs were coated with silica. The synthesized MNPs were characterised by X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA), field emission scanning electron microscope (FE-SEM), energy dispersive absorption spectroscopy (EDAX), fourier transform infra-red spectroscopy (FTIR), vibrating scanning magnetometer (VSM), zeta potential measurements and ultraviolet-visible spectroscopy (UV-Vis). The anticancer drug delivery capability of La0.7SrO.JMn03 MNPs was carried out. Silica coatings with were utilised for the loading of 5-Fluoro uracil (5-FU)- a well-known anti-cancer drug. The silica surface was functionalised with amino propyl (LSMO-Si02-NH2) to achieve charge reversal of the designed system from negative to positive as pH varied from 7.4 to 5 which was used for the effective release of the cargo at endosomal pH 5. The high 5-FU drug loading and its pH-sensitive release from LSMO-Si02-NH2 suggest that it is a promising material for targeted drug delivery application

Heavy Metal Concentration of Surface Dust Present in E-Waste Components: The Westminister Electronic Market, Lagos Case Study

To evaluate the extent of heavy metals (Cd, Cr, Pb, Zn, Fe) contamination from e-waste, surface dust samples were collected from workshops (indoor), around the market areas (outdoor) and from a distance of about 100 metres away from the market area (control) of the Westminister Electronic market in Lagos, Nigeria. Aqua regia digestion was applied to the dust samples prior to determination of heavy metal by atomic absorption spectroscopy (AAS). The AAS analysis revealed mean concentrations in indoor dust (Pb 22.50, Cd 1.80, Fe 108.00, Cr 0.35 and Zn 295.50 mg/kg), outdoor dust (Pb 15.90, Cd 19.00, Fe 103.3, Cr 0.10 and Zn 213.00 mg/kg) and control dust ( Pb 9.40, Cd -, Fe 62.00, Cr – and Zn 78.00 mg/kg). Although the result showed a relatively low contamination in general, it could be inferred that the increased concentration of heavy metals from the indoor electronic waste could be from the interaction of heavy metals in the e-waste components with the settled dust on them over time. Risk assessment predicted that Cd and Zn in the e-waste have the potential to pose serious health risks to workers, customers and local residents of Westminister area, especially children, and this underscores the urgent intervention by relevant government agencies