Emerson Leandro Silva; Igor Mendes Mateos; Marina Piacenti da Silva

Título do Trabalho

"ONE-STEP MICROWAVE-ASSISTED HYDROTHERMAL SYNTHESIS OF A NITROGEN- AND MAGNETITE-FUNCTIONALIZED GRAPHENE OXIDE NANOCOMPOSITE FOR MULTIMODAL BIOMEDICAL APPLICATIONS"

Autores

Emerson Leandro Silva
Igor Mendes Mateos
Marina Piacenti da Silva

Modalidade

Resumo

Área temática

Química dos Materiais

Data de Publicação

23/01/2026

País da Publicação

Brasil

Idioma da Publicação

pt-BR

Página do Trabalho

https://www.even3.com.br/anais/virtppgctm-571248/1413668-one-step-microwave-assisted-hydrothermal-synthesis-of-a-nitrogen--and-magnetite-functionalized-graphene-oxide-n

ISBN

978-65-272-2157-9

Palavras-Chave

graphene oxide; magnetite; hydrothermal synthesis; colloidal stability; biomedical applications.

Resumo

This work reports the synthesis and physicochemical characterization of a multifunctional nanocomposite composed of nitrogen-doped and magnetite-functionalized graphene oxide (mNGO), obtained through a one-step microwave-assisted hydrothermal route. This approach was designed to overcome the inherent limitations of conventional hydrothermal methodologies, namely, extended reaction times, the requirement for multiple synthesis stages, and poor reproducibility, by establishing a more efficient, rapid, controllable, and energetically favorable process aimed at developing materials suitable for multimodal biomedical applications. The synthesis was carried out using graphene oxide (GO) previously prepared via the modified Hummers method. Ethylene glycol played a triple role as a polar solvent, dispersing medium, and mild reducing agent, ensuring homogeneous thermal transfer and colloidal stability under microwave irradiation. Urea served as the nitrogen source, enabling heteroatomic doping of the graphene lattice through the release of ammonia-derived species during its thermal decomposition. Sodium acetate functioned as a pH modulator and coprecipitation agent, favoring controlled nucleation of iron oxide nanoparticles, while PEG-6000 acted as a steric stabilizer, preventing aggregation and promoting uniform particle dispersion. Iron incorporation was achieved using FeCl₃·6H₂O and FeCl₂·4H₂O in a 2:1 molar ratio, a condition essential for the formation of the spinel phase of magnetite (Fe₃O₄). The process was conducted in a microwave reactor (ETHOS EASY, Milestone) at 180 °C for 30 minutes, ensuring efficient energy transfer and isotropic nanoparticle growth. The obtained material exhibited a homogeneous black coloration and strong magnetic response, confirming the successful functionalization of GO with iron oxides. X-ray diffraction (XRD) confirmed the crystalline spinel structure typical of magnetite, with characteristic reflections corresponding to the (220), (311), (400), (422), (511), and (440) planes. Fourier-transform infrared spectroscopy (FT-IR) revealed partial reduction of GO, the emergence of Fe–O stretching bands around 580 cm⁻¹, and signals associated with nitrogen incorporation (C–N and N–H), confirming effective heteroatomic doping. Scanning electron microscopy (SEM) micrographs showed uniformly distributed spherical nanoparticles, with average diameters ranging from 20 to 50 nm on GO sheets, demonstrating controlled morphology and strong interfacial bonding between the magnetic and carbonaceous phases. The combination of nitrogen doping and magnetic functionalization, supported by microwave-assisted heating, resulted in a nanocomposite with synergistically integrated magnetic, structural, and photoactive properties. This single-step strategy represents a promising incremental innovation toward the development of next-generation nanobiotechnological platforms with potential applications in photothermal and photodynamic therapies, bioimaging, and controlled drug-delivery systems.

Título do Evento: 6ª Reunião Técnica do Programa de Pós-graduação em Ciência e Tecnologia de Materiais
Cidade do Evento: Presidente Prudente
Título dos Anais do Evento: Anais da 6ª Reunião Técnica do Programa de Pós-graduação em Ciência e Tecnologia de Materiais
Nome da Editora: Even3
Meio de Divulgação: Meio Digital

Como citar

SILVA, Emerson Leandro; MATEOS, Igor Mendes; SILVA, Marina Piacenti da. "ONE-STEP MICROWAVE-ASSISTED HYDROTHERMAL SYNTHESIS OF A NITROGEN- AND MAGNETITE-FUNCTIONALIZED GRAPHENE OXIDE NANOCOMPOSITE FOR MULTIMODAL BIOMEDICAL APPLICATIONS".. In: Anais da 6ª Reunião Técnica do Programa de Pós-graduação em Ciência e Tecnologia de Materiais. Anais...Presidente Prudente(SP) UNESP, 2025. Disponível em: https//www.even3.com.br/anais/virtppgctm-571248/1413668-ONE-STEP-MICROWAVE-ASSISTED-HYDROTHERMAL-SYNTHESIS-OF-A-NITROGEN--AND-MAGNETITE-FUNCTIONALIZED-GRAPHENE-OXIDE-N. Acesso em: 17/02/2026