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Today, research into nanoparticles for diagnostic and therapeutic use in cancer is on the rise. In the present study, the effect of superparamagnetic iron oxide nanoparticles on the formation of apoptosis in HT-29 cells is investigated.In this study, we investigated the mechanisms of apoptosis induced by superparamagnetic iron oxide nanoparticles after MTT assay and determining the appropriate dose of 2.5 µg / mL to induce apoptosis in HT-29 cells.Superparamagnetic iron oxide nanoparticles increased the levels of ROS, Ca2 +, and DNA damage in HT-29 cells. Also, at the level of protein and mRNA, they increased the expression of Caspes 3 and 9 and significantly decreased Bcl-2 compared to the control group (P <0.0001).Fe3O4 causes apoptosis in cancer cells by increasing the level of ROS and intracellular calcium, followed by increasing the expression of caspases 3 and 9 and decreasing the expression of Bcl-2, as well as direct DNA damage.

TiO2-based nanostructures have received great attention in the past few years owing to their promising applications in water purification systems, sterilization, self-cleaning surfaces, photoelectrochemical conversion, and hydrogen evolution. However, the low-cost and environment-friendly synthesis procedure is an important step for transferring it to commercialization and industry application. Anodizing, one of the newest and most promising procedures in nanomaterial synthesis, is an electrodeposition process for creating nanotubes by altering the surface of the titanium. A variety of parameters influence the thickness of the oxide layer and the size of the nanotube formed during this process, including time, current density, applied voltage, electrolyte solution PH, and temperature. In this work, different anodizing times of 5, 10, 15, 20, 25, and 30 min as well as various voltages are examined to achieve the best conditions for making a titanium oxide nanotube substrate. We showed that the best-synthesized titanium oxide nanotube substrate with appropriate crystal size and optoelectrical properties was produced in 30 minutes at 20 volts.

As the photoanode material, TiO2 is the backbone of cost-effective dye-sensitized solar cells. Herein, we propose a green, low-cost, and environmentally friendly synthesis method for titanium dioxide nanotubes using the anodizing process. The anodizing process was carried out in a chemical cell, and the effect of voltage and anodizing time on the creation of pure titanium dioxide nanotubes was investigated. A grade 4 titanium sheet with a thickness of 1 mm was utilized to make titanium oxide nanotubes. First, the titanium sheet was sliced into 1.5 × 1.5 cm squares, and the samples were sanded and polished with SiC sanding sheets ranging in grade from 180 to 3000. After that, the samples were immersed in an ultrasonic bath for 15 minutes to degrease and remove surface impurities in an equal amount of acetone-ethanol solution. A two-electrode cell was utilized for anodizing, with a graphite electrode as the cathode, a titanium sample as the anode, and an electrolyte solution containing 0.5 percent by weight of HF acid and 1:7 acetic acid with a pH of 3.5. The anode and cathode were separated by four centimeters. Different voltages and times were applied and studied in this experiment. Anodization was performed on samples produced at 20 and 15 volts for 15 and 30 minutes, respectively. The crystallization of titanium dioxide nanotubes, as well as their strength and stickiness, were caused by annealing these layers. The electrical characteristics, microstructure, and phases generated before and after heat treatment were investigated using XRD, FESEM, and FPP tests. The titanium dioxide nanotubes were then stacked using the DC sputtering method to increase their structural, crystallographic, and electrical properties for application in solar cells at three different distances of 3, 4, and 5 cm.