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Abstract(s)
O aquecimento por indução é um método conveniente e flexível para fornecer campos magnéticos de alta intensidade às nanopartículas, resultando em um tratamento focado e direcionado, este método está obtendo considerável interesse na comunidade de pesquisa médica. Uma das suas aplicabilidades é no tratamento contra o cancro que envolve o aquecimento das células tumorais dentro do corpo, hipertermia (ou termoterapia). O tratamento do cancro com hipertermia requer o direcionamento de uma dose de calor cuidadosamente controlada ao tumor canceroso e ao tecido corporal circundante. As nanopartículas são usadas como fontes geradoras de calor nas células cancerígenas e nos tumores. Acredita-se que o aquecimento das nanopartículas com indução seja causado por uma combinação de efeitos de histerese, efeito Néel e movimento browniano. A histerese é a reorientação contínua dos dipolos magnéticos; o campo magnético de indução imposto causa atrito que gera calor. O efeito de Néel é o aquecimento devido ao superparamagnetismo e o movimento browniano é o movimento aleatório das nanopartículas num fluido. Este trabalho prendeu-se na construção de um sistema in vitro que ao fornecer uma dada intensidade de corrente a um solenoide este gerasse um campo magnético externo. O campo magnético aumentou a temperatura do nanofluido em estudo, sendo a temperatura monitorizada pelo sistema, de forma a percebermos o comportamento das nanopartículas. O objetivo deste trabalho era testar o protótipo com nanopartículas magnéticas, mas devido as condições excecionais deste ano letivo, foi usado nanopartículas semicondutoras para testarmos o protótipo criado. Para tal foi produzido um nanofluido de grafeno, o qual teve uma excelente resposta ao campo magnético gerado, devido ao facto de ser um excelente condutor térmico.
Induction heating is a convenient and flexible method to provide high-intensity magnetic fields to nanoparticles, resulting in focused and targeted treatment, this method is gaining considerable interest in the medical research community. One of its application is in cancer treatment involving the warming of tumor cells within the body, hyperthermia (or thermotherapy). The treatment of cancer with hyperthermia requires directing a carefully controlled heat dose to the cancerous tumor and surrounding body tissue. Nanoparticles are used as heat sources in cancer cells and tumors. It is believed that the heating of the nanoparticles with induction is caused by a combination of hysteresis effects, Néel effect and Brownian motion. Hysteresis is the continuous reorientation of magnetic dipoles; the imposed magnetic fields of induction causes friction that generates heat. The Néel effect is the heating due to the superparamagnetism and the Brownian motion is the random motion of the nanoparticles in a fluid. This work was focused on the construction of an in vitro system that by providing a given current intensity to a solenoid it would generate an external magnetic field. The magnetic field increased the temperature of the nanofluid under study, being the temperature monitored by the system, in order to understand the behavior of the nanoparticles. The goal of this work was to test the prototype with magnetic nanoparticles, but due to the exceptional conditions of this school year, semiconductor nanoparticles were used to test the prototype created. In order to do this, a graphene nanofluid was produced, which had an excellent response to the generated magnetic field, due to the fact that it is an excellent thermal conductor.
Induction heating is a convenient and flexible method to provide high-intensity magnetic fields to nanoparticles, resulting in focused and targeted treatment, this method is gaining considerable interest in the medical research community. One of its application is in cancer treatment involving the warming of tumor cells within the body, hyperthermia (or thermotherapy). The treatment of cancer with hyperthermia requires directing a carefully controlled heat dose to the cancerous tumor and surrounding body tissue. Nanoparticles are used as heat sources in cancer cells and tumors. It is believed that the heating of the nanoparticles with induction is caused by a combination of hysteresis effects, Néel effect and Brownian motion. Hysteresis is the continuous reorientation of magnetic dipoles; the imposed magnetic fields of induction causes friction that generates heat. The Néel effect is the heating due to the superparamagnetism and the Brownian motion is the random motion of the nanoparticles in a fluid. This work was focused on the construction of an in vitro system that by providing a given current intensity to a solenoid it would generate an external magnetic field. The magnetic field increased the temperature of the nanofluid under study, being the temperature monitored by the system, in order to understand the behavior of the nanoparticles. The goal of this work was to test the prototype with magnetic nanoparticles, but due to the exceptional conditions of this school year, semiconductor nanoparticles were used to test the prototype created. In order to do this, a graphene nanofluid was produced, which had an excellent response to the generated magnetic field, due to the fact that it is an excellent thermal conductor.
Description
Keywords
Hipertermia Termoterapia Indução magnética Nanopartículas magnéticas Hyperthermia Thermotherapy Magnetic induction Magnetic nanoparticles