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1.
Artif Cells Nanomed Biotechnol ; 46(sup3): S725-S733, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30449175

RESUMO

Breast cancer is women's most common type of cancer, with a global rate of over 522,000 deaths per year. One of the main problems related to breast cancer relies in the early detection, as the specialized treatment. In this direction was developed, characterized and tested in vivo a smart delivery system, based on radiolabelled magnetic core mesoporous silica doped with trastuzumab as intralesional nanodrug for breast cancer imaging and possible therapy. The results showed that nanoparticles had a size of 58.9 ± 8.1 nm, with specific surface area of 872 m2/g and pore volume of 0.85 cm3/g with a pore diameter of 3.15 nm. The magnetic core mesoporous silica was efficiently labelled with 99mTc (97.5% ±0.8) and doped >98%. The cytotoxicity assay, demonstrated they are safe to use. The data were corroborated with the IC50 result of: 829.6 µg ± 43.2. The biodistribution showed an uptake by the tumour of 7.5% (systemic via) and 97.37% (intralesional) with less than 3% of these nanoparticles absorbed by healthy tissues. In a period 6-h post-injection, no barrier delimited by the tumour was crossed, corroborating the use as intralesional nanodrug.


Assuntos
Portadores de Fármacos , Nanopartículas , Dióxido de Silício , Trastuzumab , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Tamanho da Partícula , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Distribuição Tecidual , Trastuzumab/química , Trastuzumab/farmacocinética , Trastuzumab/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Control Release ; 281: 11-18, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29753960

RESUMO

Nanoparticles have specific features (lipophilicity, surface charge, composition and size). Studies regarding the biological behavior of nanoparticles in diseases such diabetics and obesity are scarce. Here, we evaluated two nanoparticles: magnetic core mesoporous silica (MSN) (58 nm) and polycaprolactone (PCL) nanoparticle (280 nm) in obese mice. Changes in the biodistribution were observed, especially considering the mononuclear phagocyte system (MPS), and the visceral fat tissue. Nonetheless, our data corroborates the influence of size in the biodistribution in obese animals, supporting that smaller nanoparticles, may show a higher tissue deposition at spleen, due the associated splenomegaly and the complications arising from this state. Finally, our study demonstrated that, in obesity, probably due the low-grade inflammatory state associated with metabolic syndrome a difference in accumulation of nanoparticles was found, with profound impact in the tissue deposition of nanoparticles.


Assuntos
Nanopartículas de Magnetita/química , Obesidade/metabolismo , Poliésteres/química , Dióxido de Silício/química , Animais , Gordura Intra-Abdominal/metabolismo , Imageamento por Ressonância Magnética/métodos , Magnetismo , Masculino , Camundongos Endogâmicos C57BL , Sistema Fagocitário Mononuclear/metabolismo , Porosidade , Distribuição Tecidual
3.
Artif Cells Nanomed Biotechnol ; 46(sup1): 1080-1087, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29482360

RESUMO

Cancer is responsible for more than 12% of all causes of death in the world, with an annual death rate of more than 7 million people. In this scenario melanoma is one of the most aggressive ones with serious limitation in early detection and therapy. In this direction we developed, characterized and tested in vivo a new drug delivery system based on magnetic core-mesoporous silica nanoparticle that has been doped with dacarbazine and labelled with technetium 99 m to be used as nano-imaging agent (nanoradiopharmaceutical) for early and differential diagnosis and melanoma by single photon emission computed tomography. The results demonstrated the ability of the magnetic core-mesoporous silica to be efficiently (>98%) doped with dacarbazine and also efficiently labelled with 99mTc (technetium 99 m) (>99%). The in vivo test, using inducted mice with melanoma, demonstrated the EPR effect of the magnetic core-mesoporous silica nanoparticles doped with dacarbazine and labelled with technetium 99 metastable when injected intratumorally and the possibility to be used as systemic injection too. In both cases, magnetic core-mesoporous silica nanoparticles doped with dacarbazine and labelled with technetium 99 metastable showed to be a reliable and efficient nano-imaging agent for melanoma.


Assuntos
Dacarbazina/química , Imãs/química , Melanoma/diagnóstico por imagem , Nanopartículas/química , Dióxido de Silício/química , Tecnécio/química , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Diagnóstico Diferencial , Detecção Precoce de Câncer , Humanos , Marcação por Isótopo , Melanoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Porosidade
4.
J Pharm Biomed Anal ; 153: 90-94, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29471223

RESUMO

The use of monoclonal antibodies (Mab) in the current medicine is increasing. Antibody-drug conjugates (ADCs) represents an increasingly and important modality for treating several types of cancer. In this area, the use of Mab associated with nanoparticles is a valuable strategy. However, the methodology used to calculate the Mab entrapment, efficiency and content is extremely expensive. In this study we developed and tested a novel very simple one-step methodology to calculate monoclonal antibody entrapment in mesoporous silica (with magnetic core) nanoparticles using the radiolabeling process as primary methodology. The magnetic core mesoporous silica were successfully developed and characterised. The PXRD analysis at high angles confirmed the presence of magnetic cores in the structures and transmission electron microscopy allowed to determine structures size (58.9 ±â€¯8.1 nm). From the isotherm curve, a specific surface area of 872 m2/g was estimated along with a pore volume of 0.85 cm3/g and an average pore diameter of 3.15 nm. The radiolabeling process to proceed the indirect determination were well-done. Trastuzumab were successfully labeled (>97%) with Tc-99m generating a clear suspension. Besides, almost all the Tc-99m used (labeling the trastuzumab) remained trapped in the surface of the mesoporous silica for a period as long as 8 h. The indirect methodology demonstrated a high entrapment in magnetic core mesoporous silica surface of Tc-99m-traztuzumab. The results confirmed the potential use from the indirect entrapment efficiency methodology using the radiolabeling process, as a one-step, easy and cheap methodology.


Assuntos
Anticorpos Monoclonais/química , Nanopartículas/química , Tecnécio/química , Magnetismo/métodos , Microscopia Eletrônica de Transmissão/métodos , Tamanho da Partícula , Dióxido de Silício/química , Trastuzumab/química
5.
Photodiagnosis Photodyn Ther ; 21: 43-49, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29126959

RESUMO

The use of nanosystems as diagnosing and therapy systems is increasing each year. There are several nanosystems available and the most prominent ones are: mesoporous silica, nanoemulsion and polymeric nanoparticles. With characteristics like low toxicology, and easy-producing process they have advantages when compared with the traditional system used, as they show specific targeting, controlled release, and higher penetration. In this study we tested three different nanocarriers (polymeric nanoparticles, nanoemulsion and mesoporous silica) containing phthalocyanineas possible PDT drugs (nanodrugs). They were tested in vitro and in vivo: cells and healthy mice, respectively, in order to understand the biological behavior and reach the initial conclusions. The results in cells showed that a dose response was observed with different concentrations of the three nanocarriers. The results in animal showed that all nanosystems have potential for application in PDT, since they were able to produce a visible effect in healthy animals.


Assuntos
Portadores de Fármacos/química , Indóis/administração & dosagem , Nanopartículas/química , Compostos Organometálicos/administração & dosagem , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Dióxido de Silício/química , Animais , Liberação Controlada de Fármacos , Emulsões/química , Isoindóis , Masculino , Camundongos , Tamanho da Partícula , Compostos de Zinco
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