Alginate vehicles are capable of forming a gel matrix in situ when they come into contact with gastric medium in the presence of calcium ions. However, the gel structure is pH dependent and can break after gastric emptying, leading to dose dumping. The aim of this work was to develop modified in situ gelling alginate formulations capable of sustaining dextromethorphan release throughout the gas...

BACKGROUND Chitosan and Alginate were used as biopolymers to prepare membranes for protein adsorption. The network requires a cross-linker able to form bridges between polymeric chains. Viscopearl-mini(®) (VM) was used as a support to synthesize them. Six different types of membranes were prepared using the main compounds of the matrix: VM, Chitosan of low and medium molecular weight, and Algin...

Four hydrophilic polymers in the form of beads - chitosan, alginate, alginate/polyvinyl alcohol (PVA), and chitosan-coated alginate - were used as supports for lipase immobilisation. Hydrogel beads were characterised by bead-size-distribution estimation, surface morphology studies, and polymer interactions assessment. Matrix performances - loading efficiency, immobilisation yield, enzyme activi...

Yeast cells immobilized by entrapment in Ba-alginate gel were investigated for growth pattern and respiratory activity. The oxygen uptake rates (OUR) of cells entrapped in gels with 4% alginate were 5.2 and 23% lower than the OUR of 2% alginate and free cells, respectively. The mass-transfer resistance offered by the matrix and growth of the entrapped cells determine a gradient of nutrients thr...

Accepted September 16, 2013 Alginate vehicles are capable of forming a gel matrix in situ when they come into contact with gastric medium in the presence of calcium ions. However, the gel structure is pH dependent and can break after gastric emptying, leading to dose dumping. The aim of this work was to develop modified in situ gelling alginate formulations capable of sustaining dextromethorpha...

Composite polymeric scaffolds from alginate and single-walled carbon nanotube (SWCNT) were produced using a freeform fabrication technique. The scaffolds were characterized for their structural, mechanical, and biological properties by scanning electron microscopy, Raman spectroscopy, tensile testing, and cell-scaffold interaction study. Three-dimensional hybrid alginate/SWCNT tissue scaffolds ...

Inspired by biosilicification, biomimetic polymer-silica nanocomposite has aroused a lot of interest from the viewpoints of both scientific research and technological applications. In this study, a novel dual functional polymer, NH₂-Alginate, is synthesized through an oxidation-amination-reduction process. The "catalysis function" ensures the as-prepared NH₂-Alginate inducing biomimetic mineral...

Alginate beads are one of the most common vehicles for encapsulation. When designing bioartificial organs, they are used as matrix for cell culture. Cell survival and activity depend essentially on the bead physical and mechanical properties. Our objective is to study the feasibility of evaluating mechanical properties of millimetric beads using an ultrasound technique. We show that Lamé’s firs...

The bacterium Pseudomonas aeruginosa causes chronic respiratory infections in cystic fibrosis (CF) patients. Such infections are extremely difficult to control because the bacteria exhibit a biofilm-mode of growth, rendering P. aeruginosa resistant to antibiotics and phagocytic cells. During the course of infection, P. aeruginosa usually undergoes a phenotypic switch to a mucoid colony, which i...

Calcium alginate beads covalently linked with alpha-cyclodextrin (alpha-CD-alginate beads) were prepared and examined for their ability to serve as a supporting matrix for bacterial degradation of nonylphenol, an endocrine disruptor. Column chromatographic experiment using alpha-CD-alginate beads with diameter of 657+/-82 microm and with degree of CD substitution of 0.16 showed a strong affinit...