Synthesis and characterization of iron oxides nanoparticles with phoactive molecules

• Grant number: 16/22482-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2017
• End date: November 30, 2019
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Principal Investigator: Paula Silvia Haddad Ferreira
• Grantee: Victor Hladkyi Toledo
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

Nanoparticles (NPs) superparamagnetic iron oxide-containing surfaces suitable ligands are commonly used for biomedical applications such as photodynamic therapy (PDT). In this scenario, this project aims the synthesis, characterization and biological assays of magnetic nanoparticles covered with silica containing photoactive molecules such as methylene blue (MB) and porphyrins. These molecules when exposed to light react with molecular oxygen leading to singlet oxygen (1O2). 1O2 is cytotoxic and causes irreversible damage to the tumor tissue. The nanoparticles will be prepared by mixture of iron chloride (II) and (III) in the presence of a weak base (NH4OH) by co-precipitation method. The NPs surfaces will be coated with cationic ligands such as tetraethylammonium. In a second step, NPs will be coated with silica layers such as sodium silicate (Na2SiO3) and tetraethylorthosilicate (TEOS) and subsequently functionalized with photoactive molecules. Structural, morphological and magnetic characterizations of these compounds as well as the evaluation of the functionalization efficiency of the photoactive molecules onto NPs surfaces will be performed by several techniques such as by X-ray diffraction (XRD), Fourier transformed infrared (FTIR), SQUID magnetic measurements, ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and dynamic light scattering. Kinetic measurements to reveal 1O2 generation by the nanoparticles upon irradiation with visible light (» = 532 nm or » = 633 nm) will also be evaluated. The aim is also to estimate the fungicidal effect of these nanosystems in fungi Candida albicans (AU)