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1.
Mater Sci Eng C Mater Biol Appl ; 43: 117-25, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25175196

RESUMO

Osseointegration of titanium implants can be improved by organic and inorganic nanocoating of the surface. The aim of our study was to evaluate the effect of organic nanocoating of titanium surface with unmodified and modified pectin Rhamnogalacturonan-Is (RG-Is) isolated from potato and apple with respect to surface properties and osteogenic response in osteoblastic cells. Nanocoatings on titanium surfaces were evaluated by scanning electron microscopy, contact angle measurements, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of coated RG-Is on cell adhesion, cell viability, bone matrix formation and mineralization was tested using SaOS-2 cells. Nanocoating with pectin RG-Is affected surface properties and in consequence changed the environment for cellular response. The cells cultured on surfaces coated with RG-Is from potato with high content of linear 1.4-linked galactose produced higher level of mineralized matrix compared with control surfaces and surfaces coated with RG-I with low content of linear 1.4-linked galactose. The study showed that the pectin RG-Is nanocoating not only changed chemical and physical titanium surface properties, but also specific coating with RG-Is containing high amount of galactan increased mineralized matrix formation of osteoblastic cells in vitro.


Assuntos
Materiais Revestidos Biocompatíveis , Nanoestruturas , Osteoblastos/citologia , Pectinas/química , Titânio , Sequência de Carboidratos , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Espectroscopia Fotoeletrônica
2.
J Biomed Mater Res A ; 102(6): 1961-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23852647

RESUMO

Osseointegration is important when implants are inserted into the bone and can be improved by biochemical surface coating of the implant. In this paper enzymatically modified rhamnogalacturonan I (RG-I) from apple and lupin was used for biochemical coating of aminated surfaces and the importance of the quality of RG-I, the nature of the binding, the fine structure of RG-I, and its effect on SaOS-2 cell line cultured on coated surfaces was investigated. SaOS-2 cells are osteoblast-like cells and a well-established in vitro model of bone-matrix forming osteoblasts. Purification by gel filtration could remove small fragments of galacturonic acid (GalA) and binding studies showed that the purity of the RG-I molecules was important for the quality of the coating. The structure of RG-I and osteoblast-like cells' viability were positively correlated so that high content of 1,4-linked galactose (Gal) and a low content of arabinose in the RG-I molecules favored cell viability. These results indicate that coating of implants with RG-I affect osseointegration positively.


Assuntos
Materiais Revestidos Biocompatíveis/química , Osteoblastos/citologia , Pectinas/química , Linhagem Celular , Sobrevivência Celular , Implantes Dentários , Humanos , Lupinus/química , Malus/química
3.
J Pharm Biomed Anal ; 80: 116-25, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23549058

RESUMO

Despite the increased request for robust quality systems, the end product may contain unidentified defects or discoloured regions. The foreign matter has to be monitored, identified and its source defined in order to prevent further contamination. However, the identification task can be complicated, since the origin and nature of foreign matter are various. The aim of this study is to provide an efficient foreign matter identification procedure for various substances possibly originating from pharmaceutical manufacturing environment. The surface or cross-section of the uncoated and coated tablets was analysed by utilization of different analytical techniques, such as light microscopy (LM), scanning electron microscopy in combination with energy dispersive X-ray microanalysis (SEM/EDX), Fourier transform infrared spectroscopy (FT-IR) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results indicate that the combination of different analytical techniques proved to be a powerful approach in foreign matter identification. Light microscopy and SEM generate information on the morphology of foreign matter particles. EDX provides elemental analysis, which most often serves as final confirmation of the identification. However, FT-IR can be used to obtain information on the compounds chemical structure and conformation, and ToF-SIMS provides sensitivity in cases, where the entire solid dosage form is contaminated with foreign matter.


Assuntos
Contaminação de Medicamentos , Nitrofurantoína/análise , Piroxicam/análise , Teofilina/análise , Espectrometria de Massas/métodos , Microscopia/métodos , Microscopia Eletrônica de Varredura/métodos , Nitrofurantoína/química , Piroxicam/química , Espectrometria por Raios X/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Comprimidos , Teofilina/química
4.
J Biomed Mater Res A ; 100(3): 654-64, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22213456

RESUMO

Long-term stability of titanium implants are dependent on a variety of factors. Nanocoating with organic molecules is one of the methods used to improve osseointegration. Therefore, the aim of this study is to evaluate the in vitro effect of nanocoating with pectic rhamnogalacturonan-I (RG-I) on surface properties and osteoblasts response. Three different RG-Is from apple and lupin pectins were modified and coated on amino-functionalized tissue culture polystyrene plates (aminated TCPS). Surface properties were evaluated by scanning electron microscopy, contact angle measurement, atomic force microscopy, and X-ray photoelectron spectroscopy. The effects of nanocoating on proliferation, matrix formation and mineralization, and expression of genes (real-time PCR) related to osteoblast differentiation and activity were tested using human osteoblast-like SaOS-2 cells. It was shown that RG-I coatings affected the surface properties. All three RG-I induced bone matrix formation and mineralization, which was also supported by the finding that gene expression levels of alkaline phosphatase, osteocalcin, and collagen type-1 were increased in cells cultured on the RG-I coated surface, indicating a more differentiated osteoblastic phenotype. This makes RG-I coating a promising and novel candidate for nanocoatings of implants.


Assuntos
Materiais Revestidos Biocompatíveis/química , Nanoestruturas/química , Osteoblastos/fisiologia , Pectinas/química , Próteses e Implantes , Animais , Linhagem Celular , Materiais Revestidos Biocompatíveis/metabolismo , Humanos , Lupinus/química , Malus/química , Teste de Materiais , Microscopia de Força Atômica , Estrutura Molecular , Osseointegração , Osteoblastos/citologia , Pectinas/metabolismo , Espectroscopia Fotoeletrônica , Propriedades de Superfície
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