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Melhoria da superfície de nanopartículas magnéticas para agentes de hipertermia inovadores no tratamento do cancro
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Resumo(s)
O cancro constitui uma das principais causas de morte a nível mundial e caracteriza-se pela proliferação descontrolada de células anormais. Infelizmente, os métodos de tratamento convencionais danificam tecidos saudáveis e não eliminam por completo as células cancerosas, conduzindo a recidivas e metástases. A hipertermia magnética constitui uma modalidade terapêutica promissora em que se utilizam nanopartículas magnéticas para induzir um aquecimento restrito à região do tumor, mediante a aplicação de um campo magnético alternado. Porém, a tendência das nanopartículas (NPs) para formar agregados em meio fisiológico requer a modificação da sua superfície com intuito de preservar a sua estabilidade coloidal e propriedades magnéticas. Neste cenário, surge o presente trabalho, em que o principal objetivo envolve a síntese e caracterização de NPs de óxido de ferro com uma superfície melhorada para aferir a sua citotoxicidade em linhas celulares Vero e SaOs-2, bem como avaliar o potencial das NPs sintetizadas como agentes de hipertermia.
A síntese via co-precipitação química com e sem tratamento hidrotermal ou por decomposição térmica em trietilenoglicol (TREG) com e sem modificação de superfície com ácido 2,3- dimercaptosuccínico (DMSA), permitiu obter NPs de magnetite hidrofílicas com um núcleo magnético de dimensão inferior a 30 nm. À exceção da amostra com DMSA, todas as NPs evidenciaram excelente biocompatibilidade in vitro. As NPs submetidas a tratamento hidrotermal exibiram uma morfologia aparentemente cúbica, distinta da forma quasi-esférica evidenciada pelas restantes, revelando-se as mais cristalinas e com melhor estabilidade coloidal após a síntese e volvido um mês. Verificou-se que a morfologia cúbica favoreceu a eficiência de aquecimento das NPs, permitindo alcançar temperaturas hipertérmicas.
Como tal, as NPs magnéticas com a superfície melhorada por tratamento hidrotermal evidenciaram maior potencial para serem estudadas como agentes de hipertermia no tratamento do cancro.
Cancer is one of the leading causes of death worldwide and is characterized by the uncontrolled proliferation of abnormal cells. Unfortunately, conventional treatment methods damage healthy tissue and do not eliminate all cancer cells, leading to relapses and metastases. Magnetic hyperthermia is a promising therapeutic modality in which magnetic nanoparticles are used to induce heating restricted to the tumor region by applying an alternating magnetic field. However, the tendency of nanoparticles (NPs) to form aggregates in physiological medium requires the modification of their surface to preserve their colloidal stability and magnetic properties. In this scenario, the present work arises, in which the main objective involves the synthesis and characterization of iron oxide NPs with an improved surface to assess their cytotoxicity in Vero and SaOs-2 cell lines, as well as to evaluate the potential of the synthesized NPs as hyperthermia agents. Synthesis via chemical co-precipitation with and without hydrothermal treatment or by thermal decomposition in triethylene glycol (TREG) with and without surface modification with 2,3-dimercaptosuccinic acid (DMSA) yielded hydrophilic magnetite NPs with a magnetic core size of less than 30 nm. Except for the sample with DMSA, all NPs showed excellent biocompatibility in vitro. The NPs submitted to hydrothermal treatment exhibited an apparently cubic morphology, distinct from the quasi-spherical shape shown by the others, being the most crystalline and with better colloidal stability after synthesis and after one month. The cubic morphology was found to favor the heating efficiency of the NPs, allowing to reach hyperthermal temperatures. As such, magnetic NPs with the surface improved by hydrothermal treatment displayed greater potential to be studied as hyperthermia agents for cancer treatment.
Cancer is one of the leading causes of death worldwide and is characterized by the uncontrolled proliferation of abnormal cells. Unfortunately, conventional treatment methods damage healthy tissue and do not eliminate all cancer cells, leading to relapses and metastases. Magnetic hyperthermia is a promising therapeutic modality in which magnetic nanoparticles are used to induce heating restricted to the tumor region by applying an alternating magnetic field. However, the tendency of nanoparticles (NPs) to form aggregates in physiological medium requires the modification of their surface to preserve their colloidal stability and magnetic properties. In this scenario, the present work arises, in which the main objective involves the synthesis and characterization of iron oxide NPs with an improved surface to assess their cytotoxicity in Vero and SaOs-2 cell lines, as well as to evaluate the potential of the synthesized NPs as hyperthermia agents. Synthesis via chemical co-precipitation with and without hydrothermal treatment or by thermal decomposition in triethylene glycol (TREG) with and without surface modification with 2,3-dimercaptosuccinic acid (DMSA) yielded hydrophilic magnetite NPs with a magnetic core size of less than 30 nm. Except for the sample with DMSA, all NPs showed excellent biocompatibility in vitro. The NPs submitted to hydrothermal treatment exhibited an apparently cubic morphology, distinct from the quasi-spherical shape shown by the others, being the most crystalline and with better colloidal stability after synthesis and after one month. The cubic morphology was found to favor the heating efficiency of the NPs, allowing to reach hyperthermal temperatures. As such, magnetic NPs with the surface improved by hydrothermal treatment displayed greater potential to be studied as hyperthermia agents for cancer treatment.
Descrição
Palavras-chave
Cancro Hipertermia magnética Nanopartículas magnéticas Melhoria da superfície Citotoxicidade in vitro