Articles
RSC Advances (20462069)14(24)pp. 16801-16808
Cobalt ferrite (CoFe) nanoparticles (NPs) with appropriate physicochemical and biological properties have attracted great attention for biomedical applications. In the present study, chitosan-coated mesoporous CoFe (CoFeCH) NPs were synthesized using a facile one-step hydrothermal method and fully characterized using FE-SEM, EDS, BET, FTIR spectroscopy, DLS, TGA, XRD, and VSM. The spherical, highly colloidal, and monodispersed CoFeCH NPs with an average hydrodynamic size of 177.9 nm, PDI of 0.238 and zeta potential value of −33 represented a high saturation magnetization value of 59.37 emu g−1. N2 adsorption-desorption analysis confirmed the mesoporous structure of CoFeCH NPs with a type IV isotherm, calculated specific surface area of 89.583 m2 g−1 and total pore volume of 0.3668 cm3 g−1. CoFeCH NPs exhibited high antibacterial effects on S. aureus and E. coli, comparable with standard antibiotics, while CH-coating led to higher biocompatibility of CoFe NPs on human cells in vitro. CoFeCH NPs also showed significant peroxidase activity with a Km value of 14.37 and specific activity of 0.632 mmol min−1. CoFeCH NPs were successfully used as a MRI contrast agent with an R2 value of 91.3 mM−1 s−1. The overall results indicated the high potential of synthesized CoFeCH NPs by the present method for biomedical applications, especially as an antibacterial and MRI contrast agent. © 2024 The Royal Society of Chemistry.
Environmental Earth Sciences (18666299)78(13)
Urmia Lake is one of the greatest salt lakes in the world and is located in the uppermost northwestern regions of Iran. In this study, in addition to trace elements, activity concentration of natural (238U, 232Th and 40K) and artificial (137Cs) radioisotopes are determined in soil and sediment specimens collected from the Urmia Lake shore by adopting gamma ray spectrometry method. The samples are analyzed for trace elements including heavy metals using atomic absorption and ICP-MS techniques. The activity concentration levels were determined for 238U (from 8 to 48 Bq kg−1), 232Th (from 7 to 64 Bq kg−1), 40K (from ≤ MDA to 631 Bq kg−1) and 137Cs (from ≤ MDA to 22 Bq kg−1) with the minimum detectable activity (MDA) of 5, 4, 63 and 4 Bq kg−1, respectively. It seems that except for the cadmium, all of the elements belong to uncontaminated to low contaminated soils group. The least correlation between 137Cs and other elements distribution in the area, confirms its anthropogenic man made source. Based on the cluster and factor analysis methods of data processing, 238U, 232Th and 40K belong to a similar group which in addition to their low geo-accumulation indexes can point to their geogenic sources, related to potassic volcanic rocks. Rare earth elements studies revealed that the main geochemical features of the sediment samples of the lake are affected by the intermediate to felsic Cenozoic volcano-plutonic rocks of the region. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
Zare, M.R.,
Kamali, M.,
Fallahi kapourchali, M.,
Bagheri, H.,
Khoram bagheri, M.,
Abedini, A.,
Pakzad, H.R. Environmental Science and Pollution Research (09441344)23(4)pp. 3285-3299
Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of 235U, 226Ra, 232Th, 40K, and 137Cs in sediment samples ranged between 1.05 ± 0.51–5.81 ± 0.61, 18.06 ± 0.63–33.36 ±.0.34, 17.57 ± 0.38–45.84 ± 6.23, 371.88 ± 6.36–652.28 ± 11.60, and 0.43 ± 0.06–63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36–5.97, 22.71–38.37, 29.27–42.89, 472.66–533, and 1.05–9.60 Bq/kg for 235U, 226Ra, 232Th, 40K, and 137Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland. © 2015, Springer-Verlag Berlin Heidelberg.
