ABSTRACT
Background: The development of green chemistry methods involving plant-based nanoparticle synthesis presents an affordable and eco-friendly approach for wastewater treatment and color removal. This study aimed to synthesize ZnO nanoparticles using the sol-gel method with Salvia officinalis and Abelmoschus esculentus plants, examining their photocatalytic efficiency for organic dye removal. Methods: To compare the properties of ZnO nanoparticles, another type of ZnO-NPs was synthesized using the co-precipitation method. The characterization of synthesized nanoparticles was performed using thermogravimetric analysis (TGA-DTG), X-ray diffraction (XRD), Dynamic Light Scattering (DLS), Zeta potential (ZP), field emission scanning electron microscopy (FE-SEM), Energy Dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), and UV-Vis spectrophotometry. Results: Based on XRD results, the average crystalline size of nanoparticles was calculated using the Debye-Scherer equation for synthesized nanoparticles using the S. officinalis at 22.99 nm and for the A. esculentus at 29.79 nm, and for the co-precipitation method at 18.83 nm. The FE-SEM images showed spherical ZnO nanoparticles. Photocatalytic properties of ZnO-NPs were investigated for remove of methylene blue organic dye in the presence of UV light. The pH 10 was identified as the best pH, which had the highest percentage of color degradation. All three types of nanoparticles were tested by up to 360 min to optimize the dyeing time. For A. esculentus, the highest percentage of color removal occurred in the first 90 min (41.0 %), for S. officinalis nanoparticles between 75 and 90 min (86.9 %), and for chemically synthesized nanoparticles between 30 and 45 min (100 %). Conclusions: In conclusion, the best MB dye degradation capacity belonged to co-precipitation ZnO nanoparticles followed by S. officinalis and A. esculentus nanoparticles.
ABSTRACT
Heavy metal exposure has soared due to the twentieth century's industrial activity. The most common heavy metals that lead to human poisoning are mercury, cadmium, and arsenic. Acute or chronic poisoning may develop following exposure to water, air, or food, so the bioaccumulation of these heavy metals causes harmful consequences in various human tissues and organs. Heavy metals interfere with biological functions such as growth, proliferation, differentiation, damage repair, and apoptosis. The mechanisms of action for these metals to cause toxicity are similar, including forming reactive oxygen species (ROS), weakening antioxidant defenses, enzyme inactivation, and oxidative stress. Heavy metal exposure is mainly associated with skin, liver, prostate, lung, urinary bladder, thyroid, and kidney cancers, as well as causing gastrointestinal malignancies. Several microRNAs (miRNAs or miRs) have been involved in various human cancers due to the dysregulation of miRNA function. Recent investigations have confirmed that microRNA dysregulation plays a role in the carcinogenesis of many tissues. This review presents the data concerning arsenic, cadmium, and mercury metals and their contamination sources, human exposure, toxicity, and inducing malignant transformations such as carcinogenicity in in-vitro or in-vivo specimens or dysregulated expression of microRNAs.
