Uso da Reciclagem de Vidros para Fins Médicos: Produção de Microesferas de Vidro Dopadas com Holmio-166 para Radioembolização Hepatocelular

Abstract

The use of recycled materials is increasingly recognized as a crucial strategy in today's global context. Glass production on a global scale, estimated at approximately 209 million tons annually, highlights the urgent need to identify alternative applications for this material. The application of microscale technologies to develop new alternatives has grown considerably, especially in selective internal therapy (SIRT) with the development of biomaterials for the treatment of hepatocellular carcinoma, using embolic agents, microspheres (spherical particles the size of a micrometer). Microspheres with additional functionalities for therapeutic embolization are currently being developed due to their properties of high surface area, high strength, durability, and ability to be loaded with radionuclides and active agents that provide an additional advantage to overcome the limitations of traditional cancer treatments. The radionuclide holmium-166 has been shown to have great SIRT therapeutic potential due to its ideal physical characteristics, such as beta emission and low radiation range. The ideal properties of microspheres are conceived through their structure, such as the choice of matrix and polymers. A glass matrix also provides sustainability to the ecosystem, due to the production of greenhouse gases that its supply provides. Data confirms that every year, around 8 million tons of glass waste are deposited in landfills without recycling, resulting in a negative environmental impact. This study describes the production of microspheres composed of recycled glass and doped with holime-166, as a controlled release system for use in hepatocellular radioembolization treatment, through distribution techniques. The results indicated that the development of microspheres was predominant, concluding that 100% of the mass of 165Ho used was incorporated into the microparticle, which presented a standard average size. Furthermore, the radionuclide incorporated into the microspheres was subjected to a nuclear reactor irradiation technique, concluding the activation of the 165Ho radionuclide into 166Ho present in the glass microspheres. Additionally, in vivo studies indicated that glass microspheres doped with 166Ho showed good tissue deposition due to ubiquitous biodistribution in different organs and high collection in the clearance organ. Finally, biochemical analyzes indicated that there is no acute liver toxicity related to the administration of glass microspheres, an overwhelming result, which confirms the results found in biodistribution. Collectively, these results strongly support the potential of recycled glass as a valuable resource for the fabrication of holmium-doped glass microspheres, offering a promising avenue for liver cancer treatment.