Publications by authors named "Niedja F Vasconcelos"

This research consolidates our group's advances in developing a therapeutic dressing with innovative enzymatic debridement, focusing on the physicochemical and in vitro biological properties of papain immobilized in wet oxidized bacterial cellulose (OxBC-Papain) dressing. OxBC membranes were produced with oxidized with NaIO, and papain was immobilized on them. They were characterized in terms of enzyme stability (over 100 days), absorption capacity, water vapor transmission (WVT), hemocompatibility, cytotoxicity, and cell adhesion.

View Article and Find Full Text PDF

Titanium is usually used in the manufacturing of metal implants due to its biocompatibility and high resistance to corrosion. A structural and functional connection between the living bone and the surface of the implant, a process called osseointegration, is mandatory for avoiding prolonged healing, infections, and tissue loss. Therefore, osseointegration is crucial for the success of the implantation procedure.

View Article and Find Full Text PDF

This review addresses the different aspects of the use of titanium and its alloys in the production of dental implants, the most common causes of implant failures and the development of improved surfaces capable of stimulating osseointegration and guaranteeing the long-term success of dental implants. Titanium is the main material for the development of dental implants; despite this, different surface modifications are studied aiming to improve the osseointegration process. Nanoscale modifications and the bioactivation of surfaces with biological molecules can promote faster healing when compared to smooth surfaces.

View Article and Find Full Text PDF

We combined the chemical and physical methods of papain immobilization through the aldehyde groups available on oxidized bacterial cellulose (OxBC) to provide high proteolytic activity for future applications as bioactive dressing. Bacterial cellulose (BC) was obtained by the fermentation of Komagataeibacter hansenii in Hestrin-Schramm medium for 5 days, followed by purification and oxidation using NaIO. Surface response methodology was used to optimize papain immobilization (2%, w/v) for 24 h.

View Article and Find Full Text PDF

This study aims to produce and characterize alginate bilayer membranes composed of single membranes with varying cross-linking degrees to modulate simvastatin release, with potential to be used for wound-dressing. The single-layer and bilayer membranes were characterized by weight, thickness, surface pH, equilibrium-humidity, swelling degree, solubility, infrared spectroscopy (attenuated total reflectance Fourier-transform infrared), scanning electron microscopy, and water vapor transmission. Simvastatin diffusion and release rates were analyzed using Franz's cells; its indirect cytotoxicity was analyzed using human keratinocyte cells.

View Article and Find Full Text PDF

Wound dressings based on natural polymers are of considerable interest in the pharmaceutical industry owing to their improved performance in the human body when compared to synthetic polymers. Alginate, a polysaccharide from brown algae, is commonly studied as a wound dressing owing to its biocompatibility and biodegradability. To improve its therapeutic features and thereby increase wound healing, papain (a proteolytic enzyme from Carica papaya latex) was proposed to be incorporated.

View Article and Find Full Text PDF

Bacterial cellulose (BC) is a polymer with interesting physical properties owing to the regular and uniform structure of its nanofibers, which are formed by amorphous (disordered) and crystalline (ordered) regions. Through hydrolysis with strong acids, it is possible to transform BC into a stable suspension of cellulose nanocrystals, adding new functionality to the material. The aim of this work was to evaluate the effects of inorganic acids on the production of BC nanocrystals (BCNCs).

View Article and Find Full Text PDF

Cellulose nanocrystals (CNCs) isolated from banana pseudostems fibers (BPF) of the Pacovan variety were used as fillers in a polyvinyl alcohol (PVOH) matrix to yield a nanocomposite. The fibers from the external fractions of the BPF were alkaline bleached and hydrolyzed under acidic conditions (H2SO4 62% w/w, 70 min, 45 °C) to obtain CNCs with a length (L) of 135.0 ± 12.

View Article and Find Full Text PDF