Superparamagnetic iron oxide nanoparticles (SPIONs) have the potential to be used as multimodal imaging and cancer therapy agents due to their excellent magnetism and ability to generate reactive oxygen species when exposed to light. We report the synthesis of highly biocompatible SPIONs through a facile green approach using fruit peel extracts as the biogenic reductant. This green synthesis protocol involves the stabilization of SPIONs through coordination of different phytochemicals. The SPIONs were functionalized with polyethylene glycol (PEG)-6000 and succinic acid and were extensively characterized by X-ray diffraction analysis, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, Rutherford backscattering spectrometry, diffused reflectance spectroscopy, fluorescence emission, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and magnetization analysis. The developed SPIONs were found to be stable, almost spherical with a size range of 17–25 nm. They exhibited excellent water dispersibility, colloidal stability, and relatively high
R
2
relaxivity (225 mM
−1
s
−1
). Cell viability assay data revealed that PEGylation or carboxylation appears to significantly shield the surface of the particles but does not lead to improved cytocompatibility. A highly significant increase of reactive oxygen species in light-exposed samples was found to play an important role in the photokilling of human cervical epithelial malignant carcinoma (HeLa) cells. The bio-SPIONs developed are highly favorable for various biomedical applications without risking interference from potentially toxic reagents.
AbstractIn the last decade, radiation physics brought about a revolution in health science by improving scientific equipment and useful methodologies for measurement. Human beings are affected by ionizing radiations that radiate from radioactive elements. The quantity of radioactive elements is different inside and outside the earth’s surface. Soil and water are exigencies of human lives which are contaminated by radioactive elements. These radioactive elements enter into the human body through drinking, eating and breathing. On reaching hazardous limits in the human body, these radioactive elements cause stomach cancer, lung cancer and leukemia. Measurement of radioactive elements in soil and water is helpful in monitoring the health issues caused by exposure to these elements. In Iraq, numerous studies about natural radioactivity, radon concentration and physiochemical parameters have been conducted by different researchers, of which most of the studies were conducted in Barsa, Nasirya, Najaf, Karbala, Baghdad, Balad, Kirkuk, Erbil, Mosul and Dohuk cities. This article aims to review and compile the studies conducted in these cities of Iraq from 2011 to 2019. In most articles, high-purity germanium (HPGe), RAD7 and CR-39 detectors are used for radioactivity and radon measurement. These cities are located in the low-high folded and Mesopotamian zones. From this study, it can be concluded that radon concentration in soil and water was greater in the Mesopotamian and lower in the low-high folded zones. Higher concentrations of natural radioactivity in water and soil were found in the low-high folded zone in Iraq. However, most of the conducted studies show that concentrations of radon and natural radioactivity are above the permissible limits recommended by the International Commission on Radiological Protection (ICRP) and World Health Organization (WHO). The values of physiochemical parameters were found to be greater in the Mesopotamian zone, but overall they are not above the permissible limits.
ObjectivesThe aim of this study is to compare the natural radioactivity and excess life time cancer risk (ELCR) factor of soil in different regions of Pakistan during last decade. Soil contains various elements and compounds including naturally occurring radioactive elements (238U, 232Th, 40K and 137Cs). Human being, animals and plants are in health risk by contaminations of natural radioactivity in soil and environmental radiometric pollution. Transferring of large amount of the natural radioactive elements in human body by nutrients may cause carcinogenic effects in human body. Pakistani soil has six types as Indus Basin Soil, Bongar Soil, Khaddar Soil, Indus delta soil, Mountainous soil and Sandy Desert Soil. In some northern region of Pakistan, naturally occurring radioactive rocks like uranuium-238 and iridium concentrations present in Gharwandi, Aram, Kingri S, Vitakri Fort Munro, Dera Bugti, Kohlu and Sibbi districts.MethodsIn this reviewed data, gamma rays spectroscopy used to determine the concentrations of 238U, 232Th and 40K with the help of High Purity Germanium (HPGe) detectors. Only the data of HPGe detector collected because of comparisons of different regions of Pakistan.Results and conclusionsMostly, different gamma rays energy peaks of relevant daughter radionuclides of radioactive element were used such as the energy peak lines of daughter radionuclides 214Pb (295.21 and 352 KeV) and 214Bi (609 and 1,120 KeV) used for calculating the 226Ra concentration in soil. In the recent study, it is concluded that average values of concentrations of natural radioactivity in soil in central and north regions of Pakistan are higher than permissible limit but found permissible range in south region of Pakistan. Mean values of ELCR factor were found higher, equal and lower in central, north and south regions than permissible limit, respectively. Generally, no serious health hazard due to natural radioactivity in soil were found.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.