Search results for "alginate"
showing 10 items of 88 documents
Hepatocytes cultured in alginate microspheres: an optimized technique to study enzyme induction.
2004
An important application of hepatocyte cultures is identification of drugs acting as inducers of biotransformation enzymes that alter metabolic clearance of other therapeutic agents. In the present study we optimized an in vitro system with hepatocytes cultured in alginate microspheres that allow studies of enzyme induction with excellent sensitivity. Induction factors obtained with standard inducers, such as 3-methylcholanthrene or phenobarbital, were higher compared to those with conventional hepatocyte co-cultures on collagen coated dishes. This is illustrated by activities of 7-ethoxyresorufin-O-deethylase (EROD) after incubation with 5 microM 3-methylcholanthrene (3-MC), a standard ind…
Effect of media composition on long-term in vitro stability of barium alginate and polyacrylic acid multilayer microcapsules.
2000
For a number of applications stability of microcapsules is a critical factor. Since the maintenance of polyelectrolyte complexes depends considerably on the ion composition we tested the physical properties of barium alginate capsules and searched for conditions to improve stability by a multilayer coating with polyethylenimine (PEI) and polyacrylic acid (PAA). Mechanical stability and diameters were determined in barium alginate capsules and compared with multilayer capsules. Multilayer coating resulted in smaller capsules than barium complexing alone. The difference was more pronounced when CaCl2 was used instead of NaCl during coating. Barium alginate capsules and application of CaCl2 du…
A scalable three-dimensional porous λ-MnO2/rGO/Ca-alginate composite electroactive film with potential-responsive ion-pumping effect for selective re…
2021
Abstract A scalable three-dimensional (3D) porous composite electroactive film consisting of λ-MnO2, reduced graphene oxide (rGO) and calcium alginate (Ca-alg) was successfully fabricated and employed for the selective extraction of Li+ ions with low concentration via an electrochemically switched ion exchange (ESIX) technology. The Li+ ion adsorption capacity of the obtained λ-MnO2/rGO/Ca-alg composite electroactive film reached as high as 32.7 mg g−1 and more than 90% of its equilibrium adsorption capacity was achieved in 1 h. The λ-MnO2/rGO/Ca-alg composite electroactive film displayed evident selectivity towards Li+ ions. The separation factors for Li+/Na+ and Li+/Mg2+ reached 1040.57 a…
Safely Dissolvable and Healable Active Packaging Films Based on Alginate and Pectin
2019
Extensive usage of long-lasting petroleum based plastics for short-lived application such as packaging has raised concerns regarding their role in environmental pollution. In this research, we have developed active, healable, and safely dissolvable alginate-pectin based biocomposites that have potential applications in food packaging. The morphological study revealed the rough surface of these biocomposite films. Tensile properties indicated that the fabricated samples have mechanical properties in the range of commercially available packaging films while possessing excellent healing efficiency. Biocomposite films exhibited higher hydrophobicity properties compared to neat alginate films. T…
Physical characterization of alginate-Pluronic F127 gel for endoluminal NABDs delivery
2014
Here we focus the attention on the physical characteristics of a highly biocompatible hydrogel made up of crosslinked alginate and Pluronic F127 (PF127). This is a composite polymeric blend we propose for artery endoluminal delivery of an emerging class of molecules named nucleic acid based drugs (NABDs). The physical characterization of our composite gel, i.e. mesh size distribution and PF127-alginate mutual organization after crosslinking, can significantly determine the NABDs release kinetics. Thus, to explore these aspects, different technical approaches, i.e. rheology, low/high field NMR and TEM, were used. While rheology provided information at the macroscopic and nano-level, the othe…
SORPTION OF CD2+ AND CU2+ IONS FROM AQUEOUS SOLUTIONS BY ALGINATE AND ALGINATE/PECTIN GEL BEADS.
2012
Removal of toxic metal ions from natural waters, wastewaters and contaminated sites is of great importance for the health of living organism and for environmental protection (1). Alternatively to the conventional chemical treatments, such as precipitation, reverse osmosis, etc, that are expensive and of high environmental impact, the use of low cost and environmental friendly sorbent materials is a very promising new technology for meal ions removal (2,3). The most investigated sorbent materials are of organic origin derived from the natural biomass (algae, fungi, bacteria) and from industrial processes, such as wood, agriculture, fishery, textile manufacturing, etc. Also some inorganic mat…
Produzione di semi sintetici di Capparis spinosa (L.). Innovazione e tradizione
2011
The caper bush (Capparis spinosa L.) is a rupiculous species. It is widespread on rocky areas and it grows on different soil associations. Caper can be propagated from fresh seeds, gathered from ripe fruit, or by stem cuttings both methods with unsatisfying results, due to the low germination percentage and to the season-dependent answer of the cutting technique. The aim of the present research has been to evaluate the attitude, for caper in vitro propagules , to be encapsulated. Micro cuttings from in vitro plantlets, were dissected and put on two different Murashige and Skoog liquid media enriched with 4% sodium alginate and 1,4% di CaCl2 separately, for the encapsulation. The synthetic s…
Resistance of Immobilized Lactic Acid Bacteria to the Inhibitory Effect of Quaternary Ammonium Sanitizers
2001
Abstract The inhibitory effect of quaternary ammonium sanitizers (QAS) on the fermentation activity of lactic acid bacteria was investigated. Benzalkonium chloride and didecyl dimethyl ammonium chloride show the same inhibitory effect. In MRS agar medium and MRS liquid medium their minimum inhibitory concentration was below 2 μg/mL. Interfering molecules in milk increased this concentration of inhibitory QAS above 8 μg/mL. Both growth and acidification were decreased but by immobilizing cells in calcium alginate gel beads this inhibitory effect could be reduced. The longer the beads were used for successive acidification and were colonized by lactic acid bacteria, the better was the acidifi…
New nanobiohybrid engineering composed of titanate nanoribbons for regenerative medicine
2012
This research work is devoted to new nanohybrid engineering composed of titanate nanoribbons for regenerative medicine. Over a first phase, nanoribbons were synthesized by hydrothermal treatment and their morphological, structural and chemical features were defined. A fine characterization by means of different techniques of transmission electron microscopy mainly enabled to determine their thickness; dimension which had never been measured so far. Subsequently, titanate nanoribbons were functionalized by different home-made heterobifunctional PEG. Those polymers present at one of their extremities specific functional groups being able to couple with numerous biological molecules. Some coll…
Magnetic hybrid TiO 2 /Alg/FeNPs triads for the efficient removal of methylene blue from water
2018
A new adsorbent material with combined adsorption, photocatalytic, and magnetic properties has been suc- cessfully synthesized and tested for the efficient dye removal from methylene blue (MB) contaminated water. A facile non-thermal method was applied to synthesize a hybrid nanocomposite consisting of TiO2/calcium algi- nate (TiO/Alg) and magnetite (Fe3O4) nanoparticles (FeNPs). The potential of the adsorbent Alg as a barrier to prevent direct contact between the magnetic core and TiO2 was experimented by varying the synthesis condi- tions. The performance of four differently synthesized TiO2/Alg/FeNPs samples (TiO2/Alg/FeNPs-1, TiO2/Alg/ FeNPs-2, TiO2/Alg/FeNPs-3, and TiO2/Alg/FeNPs-4) wa…