title: Synthesis, characterization, and biodistribution studies of (99m)Tc-labeled SBA-16 mesoporous silica nanoparticles.
abstract: Along with anti-cancer drug delivery researches, many efforts have been done to develop new tracers for diagnostic applications. Based on advances in molecular imaging, nanoparticles can be used to visualize, characterize and measure biological process at molecular and cellular level. Therefore, the purpose of this study was to synthesize, characterize and radiolabeled mesoporous silica nanoparticles (MSNs) for in vivo applications. The nanoparticles were synthesized, functionalized with 3-aminopropyltriethoxysilane (APTES) and then, anchored with diethylenetriaminepentaacetic acid (DTPA). Particles were physicochemical characterized by elemental analysis (CHN), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and zeta potential, and were morphologically characterized by scanning electron microscopy (SEM), low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. Results indicate that functionalization process was successfully achieved. Next, functionalized silica nanoparticles were radiolabeled with technetium-99m showing high radiochemical yields and high radiolabeled stability. These findings allow the use of the particles for in vivo applications. Biodistribution and scintigraphic images were carried out in healthy mice in order to determine the fate of the particles. Results from in vivo experiments showed high uptake by liver, as expected due to phagocytosis. However, particles also showed a significant uptake in the lungs, indicated by high lung-to-non-target tissue ratio. In summary, taking into account the great potential of these silica mesoporous structures to carry molecules this platform could be a good strategy for theranostic purposes.
authors.affiliation: Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Minas Gerais, Brazil; Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: André Luís Branco
authors.initials: AL
authors.lastname: de Barros
authors.affiliation: Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Karina Silva
authors.initials: KS
authors.lastname: de Oliveira Ferraz
authors.affiliation: Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Thais Cristina Soares
authors.initials: TC
authors.lastname: Dantas
authors.affiliation: Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Gracielle Ferreira
authors.initials: GF
authors.lastname: Andrade
authors.affiliation: Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Valbert Nascimento
authors.initials: VN
authors.lastname: Cardoso
authors.affiliation: Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Minas Gerais, Brazil. Electronic address: sousaem@cdtn.br.
authors.forename: Edésia Martins Barros de
authors.initials: EM
authors.lastname: Sousa
mesh_terms: D000818:Animals; D007553:Isotope Labeling; D008422:Materials Testing; D051379:Mice; D057054:Molecular Imaging / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D013667:Technetium / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: C000600619:SBA-16; D013667:Technetium; D012822:Silicon Dioxide
keywords: Diagnosis; Mesoporous silica nanoparticles; Radiolabeled nanoparticles; SBA-16; Scintigraphic imaging; Technetium-99m