A modular approach to study protein adsorption on surface modified hydroxyapatite

Biocompatible inorganic nano- and microcarriers can be suitable candidates for protein delivery. This study demonstrates facile methods of functionalization by using nanoscale linker molecules to change the protein adsorption capacity of hydroxyapatite (HA) powder. The adsorption capacity of bovine serum albumin as a model protein has been studied with respect to the surface modifications. The selected linker molecules (lysine, arginine, and phosphoserine) can influence the adsorption capacity by changing the electrostatic nature of the HA surface. Qualitative and quantitative analyses of linker-molecule interactions with the HA surface have been performed by using NMR spectroscopy, zeta-potential measurements, X-ray photoelectron spectroscopy, and thermogravimetric analyses. Additionally, correlations to theoretical isotherm models have been calculated with respect to Langmuir and Freundlich isotherms. Lysine and arginine increased the protein adsorption, whereas phosphoserine reduced the protein adsorption. The results show that the adsorption capacity can be controlled with different functionalization, depending on the protein-carrier selections under consideration. The scientific knowledge acquired from this study can be applied in various biotechnological applications that involve biomolecule-inorganic material interfaces.

Surface modified Mg-doped ZnO QDs for biological imaging

Fundação Amparo à Pesquisa Estado de São Paulo (FAPESP)

Liquid crystalline formulations containing modified surface TiO2 nanoparticles obtained by sol-gel process

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adsorption of MX2 (M = Mn, Ni, Cu, Zn, and Cd; X = Cl, Br, and I) and FeCl3 by modified silica surface with imidazolylpropyl group

Silica gel surface modified with imidazolylpropyl group was used to adsorb MX2 (M = Mn, Ni, Cu, Zn, and Cd; X = Cl, Br, and I) and FeCl3 from ethanol and acetone solution. The adsorption capacity and the intensity of the adsorption were determined by using the Langmuir equation. The influences of the solvent, temperature, and degree of functionalization on the adsorption were also studied. The infrared spectra of the functionalized silica were recorded between 1700-1300 cm-1. The bands of the imidazole skeletal vibrations are shifted to higher frequencies upon metal-to-base nitrogen interaction. © 1985.

Biomedical Ti-Mo Alloys with Surface Machined and Modified by Laser Beam: Biomechanical, Histological, and Histometric Analysis in Rabbits

Purpose: In vivo bone response was assessed by removal torque, hystological and histometrical analysis on a recently developed biomedical Ti-15Mo alloy, after surface modification by laser beam irradiation, installed in the tibia of rabbits. Materials and Methods: A total of 32 wide cylindrical Ti-15Mo dental implants were obtained (10mm × 3.75mm). The implants were divided into two groups: 1) control samples (Machined surface - MS) and 2) implants with their surface modified by Laser beam-irradiation (Test samples - LS). Six implants of each surface were used for removal torque test and 10 of each surface for histological and histometrical analysis. The implants were placed in the tibial metaphyses of rabbits. Results: Average removal torque was 51.5Ncm to MS and >90Ncm to LS. Bone-to-implant-contact percentage was significantly higher for LS implants both in the cortical and marrow regions. Conclusions: The present study demonstrated that laser treated Ti-15Mo alloys are promising materials for biomedical application. © 2011 Wiley Periodicals, Inc.

Hydroxyapatite deposition study through polymeric process on commercially pure Ti surfaces modified by laser beam irradiation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Electrode surface modifications improve cathode hydrogen production and anode capacity in Ni-MH batteries

This paper reports results from electrochemical evaluations of electrodes used as cathodes for a hydrogen evolution reaction and anodes in Ni-MH batteries that had been surface-modified by micro-encapsulation, co-deposition and sol-gel methods. The surface modifications produced actual improvements in the corresponding electrochemical reactions by enhancing the performance and/or the mechanical stability of the electrode material. (c) 2005 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.

Efeito da adição de argilas modificadas na estrutura e propriedades funcionais de biofilmes produzidos a base de zeína

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo sobre desruptores endócrinos em sistemas aquáticos: detecção e perspectivas de tratamento das águas do Rio Aporé-MS/GO, utilizando-se adsorventes sólidos

Pós-graduação em Ciência dos Materiais - FEIS

Evaluation of modified silica nanoparticles in carboxylated nitrile rubber nanocomposites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Analysis of implants with laser irradiated surface and silicate deposition

Objectives: the purpose of this study was to evaluate the surfaces of commercially pure titanium (cpTi) implants surface modified by laser beam (LS), by laser beam associated with sodium silicate deposition (SS) and compare them with surfaces modified by dual-acid etched (AS) and with machined surface (MS). Methods: thirty rabbits received two implants each (one for each tibia). After 30, 60 and 90 days postoperative, the implants were removed by reverse torque for biomechanical analysis and surfaces were analyzed by scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS). Results: the mean values of reverse torque at 30, 60 and 90 days postoperative were respectively 24.60, 43.60 e 60.40 N.cm to MS, 43.00, 68.20 e 63.80 N.cm to AS group, 59.80, 76.60 e 78.00 N.cm to LS group and 63.00, 75.40 e 76.60 N.cm to SS group. At 30 days, LS and SS groups showed statistically significant difference (p<0.05) compared to the other groups. At 60 days, LS and SS groups showed statistically significant difference (p<0.05) when compared to MS. Conclusions: it was concluded that SL and SS implants' biomechanical and topographical properties increased bone-implant interaction when compared to the AS and MS implants.

Adsorção-fotodegradação do herbicida paraquate em água pela argila Na-Bentonita e por novos materiais TiO2-Bentonita, TiO2/ZnOBentonita, Al/Fe-Bentonita e Al/Fe.Cu-Bentonita

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Surface engineering of silica nanoparticles for oral insulin delivery: characterization and cell toxicity studies

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detection of several carbohydrates using boron-doped diamond electrodes modified with nickel hydroxide nanoparticles

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Carbon-coated SnO2 nanobelts and nanoparticles by single catalytic step

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)