Search results for "SAC"
showing 10 items of 3337 documents
Spray-Drying, Solvent-Casting and Freeze-Drying Techniques: a Comparative Study on their Suitability for the Enhancement of Drug Dissolution Rates.
2019
Purpose Solid dispersions (SDs) represent the most common formulation technique used to increase the dissolution rate of a drug. In this work, the three most common methods used to prepare SDs, namely spray-drying, solvent-casting and freezedrying, have been compared in order to investigate their effect on increasing drug dissolution rate. Methods Three formulation strategies were used to prepare a polymer mixture of polyvinyl-alcohol (PVA) and maltodextrin (MDX) as SDs loaded with the following three model drugs, all of which possess a poor solubility: Olanzapine, Dexamethasone, and Triamcinolone acetonide. The SDs obtained were analysed and compared in terms of drug particle size, drug-lo…
A Magnetostrictive Electric Power Generator for energy harvesting from traffic: Design and experimental verification
2015
In the last decades, the growth in energy demand, the decrease of fossil fuels available in the market and the impact of anthropogenic factors on climate change has given new impulse to research on renewable energy systems, particularly those known as energy harvesting devices (EHDs) [1]. A large number of EHDs have been proposed, using different operating principle [1-4]. Among them, piezoelectric and magnetostrictive seem to be particularly suitable for the application in EHD. In these materials the application of external mechanical stress induces a change in the level of magnetization and therefore an electromotive force (emf) can be generated and collected in order to produce electrica…
Green Nanocomposites-Based on PLA and Natural Organic Fillers
2017
Over the past decades, many efforts have been carried out for the development of novel green nanocomposites based on biopolymers and natural organic nanofillers. Indeed, these nanocomposites could replace some oil-derived polymers and thus helping to overcome environmental problems. In this regard, poly (lactic acid) (PLA) as matrix and polysaccharide nanocrystals (cellulose, chitin, and starch) as bio-based nanoreinforcements are the most promising components to obtain high-performance green nanocomposites. This chapter covers the basic features of PLA and polysaccharide nanocrystals derived from biomass-based raw materials such as cellulose, chitin, and starch. In particular, this chapter…
Zirconia nanocrystals as submicron level biological label
2012
Inorganic nanocrystals are of increasing interest for their usage in biology and pharmacology research. Our interest was to justify ZrO2 nanocrystal usage as submicron level biological label in baker's yeast Saccharomyces cerevisia culture. For the first time (to our knowledge) images with sub micro up-conversion luminescent particles in biologic media were made. A set of undoped as well as Er and Yb doped ZrO2 samples at different concentrations were prepared by sol-gel method. The up-conversion luminescence for free standing and for nanocrystals with baker's yeast cells was studied and the differences in up-conversion luminescence spectra were analyzed. In vivo toxic effects of ZrO2 nanoc…
Core-shell PLA/Kef hybrid scaffolds for skin tissue engineering applications prepared by direct kefiran coating on PLA electrospun fibers optimized v…
2021
Abstract Over the recent years, there is a growing interest in electrospun hybrid scaffolds composed of synthetic and natural polymers that can support cell attachment and proliferation. In this work, the physical and biological properties of polylactic acid (PLA) electrospun mats coated with kefiran (Kef) were evaluated. Gravimetric, spectroscopic (FTIR-ATR) and morphological investigations via scanning electron microscopy confirmed the effective formation of a thin kefiran layer wrapped on the PLA fibers with an easy-tunable thickness. Air plasma pre-treatment carried out on PLA (P-PLA) affected both the morphology and the crystallinity of Kef coating as confirmed by differential scanning…
Polysaccharides/Halloysite nanotubes for smart bionanocomposite materials.
2020
Biopolymers as alternative to fossils-derived polymers are attracting the interest of researcher in material science. Besides the economic advantages, the sustainability makes polysaccharides ideal candidates to prepare films and formulations. The addition of Halloysite nanotubes as green inorganic fillers was exploited to improve the physico-chemical properties and to introduce smart response abilities to the material. Halloysite is a natural tubular nanomaterial with hollow cavity and large aspect ratio. The effect of polymer charge on the morphology and mesoscopic properties of polysaccharides/halloysite nanocomposites has been highlighted. Different strategies (solvent casting, lyophili…
Efficient boron removal by using mesoporous matrices grafted with saccharides.
2004
Highly efficient boron removal from water was achieved by using mesoporous silica materials functionalised with saccharides. Beltran Porter, Daniel, Daniel.Beltran@uv.es ; Amoros del Toro, Pedro Jose, Pedro.Amoros@uv.es
Thermal restraint of a bacterial exopolysaccharide of shallow vent origin
2018
This is the post-print version of the following article: "Thermal restraint of a bacterial exopolysaccharide of shallow vent origin", which has been published in final form at https://www.sciencedirect.com/science/article/pii/S0141813018308250?via%3Dihub; International audience; To dynamically characterize the thermal properties of the fructose-rich exopolysaccharide (EPS1-T14), produced by themarine thermophilic Bacillus licheniformis T14, the Attenuated Total Reflectance Fourier Transform Infra-Redspectroscopy was coupled to variable temperature ranging from ambient to 80 °C.The spectra were analyzed by the following innovative mathematical tools: i) non-ideal spectral deviation, ii) OHst…
Preparation and Characterization of Gold Nanorods Coated with Gellan Gum and Lipoic Acid
2020
Gold nanorods (AuNRs) can combine therapeutic hyperthermia with diagnostic features, representing a smart choice to address personalized cancer treatments. In this regard, a crucial quest is the selection of the right biocompatible coating agent able to stabilize them in the physiological environment, further endowing the possibility to load bioactive molecules and/or targeting moieties. Therefore, AuNRs optical properties can be successfully merged with advantageous materials features to obtain selective photothermal therapy (PTT) systems. Here, the natural materials lipoic acid (LA) and the polysaccharide gellan gum (GG) were chosen to prepare three types of stabilized gold nanorods, usin…
A genetic algorithm for the minimum generating set problem
2016
Graphical abstractDisplay Omitted HighlightsWe propose a novel formulation for the MGS problem based on multiple knapsack.The so-conceived MGS problem is solved by a novel GA.The GA embeds an intelligent construction method and specialized crossover operators.We perform a thorough comparison with regards to state-of-the-art algorithms.The proposal proves to be very competitive, specially for large and hard instances. Given a set of positive integers S, the minimum generating set problem consists in finding a set of positive integers T with a minimum cardinality such that every element of S can be expressed as the sum of a subset of elements in T. It constitutes a natural problem in combinat…