مقالات پذیرفته شده در ششمین کنگره بین المللی زیست پزشکی
The efficiency of titanium dioxide nanoparticles as contrast agents in radiotherapy of tumor
The efficiency of titanium dioxide nanoparticles as contrast agents in radiotherapy of tumor
Fatemeh Davodabadi,1Saman Sargazi,2,*
1. Department of Biology, Faculty of Basic Science, Payame Noor University, Tehran, Iran. 2. Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious,Diseases, Zahedan University of Medical Sciences, Zahedan, Iran
Introduction: Conventional non-nanoparticle image contrast agents such as iodine have been validated for radiotherapy enhancement applications. Ionizing radiation is used to treat tumors during radiotherapy. This causes damage to DNA and other biomolecules in the tumor, leading to cell death. Radiation therapy has the inherent drawback of inflicting radiation on the surrounding healthy tissues of the treated tumor. Some tumors are unsuitable for radiotherapy since the dose required to destroy the tumor may harm the surrounding healthy tissue. In radiation therapy applications, titanium dioxide nanoparticles (TiO2-NPs) have been found to have absorptive properties and a higher refractive index, which can be beneficial for the treatment of cancer.
Methods: We searched Google Scholar, Web of Science, PubMed, and Scopus databases for published articles related to titanium dioxide, diagnosis, cancer, and radiotherapy using the keywords titanium dioxide, diagnosis, cancer, and radiotherapy. Reviews were conducted on articles published.
Results: As a radio-sensitizer for radiotherapy of triple-negative breast cancer (TNBC), hybrid anisotropic nanostructure is composed of gold-doped titanium dioxide (TiO2). Sonodynamic therapy (SDT) with ultrasonic activated TiO2 for increased quantum yield. According to Yang et al., when titanium dioxide was exposed to ultrasound, carbon-doped titanium dioxide generated ROS, eliminating tumor cells. A cancer catalytic internal radiotherapy (CIRT) system that utilizes auger electrons (AEs) to construct an active site is reported by Su et al. Radiation therapy using contrast agents and kilovoltage X-rays (contrast-enhanced radiotherapy or CERT) is called contrast-enhanced radiotherapy. Consequently, a high Z content in materials can affect the distribution of absorbed doses because they have different absorption properties from healthy tissues. A localized dose increase can be achieved in areas containing contrast agents without affecting healthy tissues. Since photo-absorbing properties change with kilovolt energy, the kilovolt range is ideal for CERT. Medical linear accelerators (Linacs) also provide X-ray energy in the megavolt range, improving contrast. Cell membranes can be penetrated by TiO2-NPs with a size under 100 nm, causing them to accumulate in cancer cells. Furthermore, it can be used as a contrast agent. In order to monitor NPs synthesized for radiotherapy and ionizing radiation with CT scanners, the standard imaging tool for planning and diagnosing treatment, it would be useful to monitor them with CT scanners. These CT scanners are gradually replacing radiotherapy treatment planning simulators. Iodine CERT can also be used to deliver therapeutic doses of X-rays to a conventional CT scanner. A similar dose distribution can be generated by this method so that simulations, hybrid imaging, and treatment can be performed on the same basis as with 10 MV therapy. An alternative that is similar to this would be highly desirable in the case of more advanced contrast agentsThese TiO2-NPs are not only contrast agents, but can also be used as radiotherapy enhancement agents and cancer-fighters.
Conclusion: As a contrast agent, TiO2-NPs are effective in diagnosing and treating cancer in these studies. Unmodified TiO2-NPs have not mainly been studied in imaging studies, whereas chemically modified TiO2-NPs have been studied in imaging studies.