Development and optimisation of spironolactone nanoparticles for enhanced dissolution rates and stability

Stable solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) formulations to enhance the dissolution rates of poorly soluble drug spironolactone (SP) were being developed. Probe ultra-sonication method was used to prepare SLNs and NLCs. All NLCs contained stearic acid (solid lipid carrier) and oleic acid (liquid lipid content), whereas, SLNs were prepared and optimised by using the solid lipid only. The particles were characterised in terms of particle size analysis, thermal behaviour, morphology, stability and in vitro release. The zeta sizer data revealed that the increase in the concentration of oleic acid in the formulations reduced the mean particle size and the zeta potential. The increase in concentration of oleic acid from 0 to 30% (w/w) resulted in a higher entrapment efficiency. All nanoparticles were almost spherically shaped with an average particle size of about ∼170 nm. The DSC traces revealed that the presence of oleic acid in the NLC formulations resulted in a shift in the melting endotherms to a higher temperature. This could be attributed to a good long-term stability of the nanoparticles. The stability results showed that the particle size remained smaller in NLC compared to that of SLN formulations after 6 months at various temperatures. The dissolution study showed about a 5.1- to 7.2-fold increase in the release of the drug in 2 h compared to the raw drug. Comparing all nanoparticle formulations indicated that the NLC composition with a ratio of 70:30 (solid:liquid lipid) is the most suitable formulation with desired drug dissolution rates, entrapment efficiency and physical stability

Élaboration par CVD de WSe

Nous présentons les premiers résultats de l’étude des conditions de préparation, par CVD, de WSe2 en couches minces. Nous avons utilisé un appareillage classique de CVD (à parois chaudes) fonctionnant à pression atmosphérique et utilisant WF6 et H2Se comme agents vecteurs de W et de Se. les couches déposées sur des substrats de nature différente (Quartz, silice, alumine, mica et différents métaux), dans un intervalle de température allant de 300°C à 700°C, ont été caractérisées par différentes techniques: RBS, RX, EDAX, microscopie optique et électronique à balayage. Ces analyses montrent qu’on peut obtenir dans certaines conditions, des couches stoechiométriques (NSe/NW = 2) présentant une cristallisation préférentielle marquée. Les spectres d’absorption optique obtenus avec ces couches sont semblables à ceux des monocristaux et leur stabilité photoélectrochimique est très bonne

Pickering Emulsions Stabilised by Biodegradable Particles Offer a Double Level of Controlled Delivery of Hydrophobic Drugs

International audienc

Diagnosis of Geomorphological Hazard in Semiarid Urban Areas. Case Study of Bou-Saada (Algerie)

peer reviewedThe study aims to emphasize the hazard diversity in the warm semi-arid climate areas, beginning from the concrete analyze of the Bou-Saada city (Algeria). Bou-Saada is situated at the contact of the Hodna shot with the Presaharian Atlas in the proximity of a corridor, which allows the orientation of the air masses. The extinction of the city has lead to the partial destruction of the oasis, as well as the exposition to the different risk phenomena, being frequent the following: - The exposition to the sand accumulation, especially of the district developed on the Southern-Western corridor, in the wind direction; - The exposition to the rock falls from the mountain side, in the conditions of a powerful desegregation; - The exposition to the inundations during the rare torrential rains, being also facilitated by the city development in a narrow depression, which allows quick running of water from the mountain side. The main factors determining the quality of the geomorphological vulnerability to the hazards (geological, geomorphological, climatic, anthropogenetic, biopedogeographical) highlight the favourability of the position of the first nucleus of the settlement compared to its area of current expansion. The research was made in many campaigns between the years of 2006-2008, within an agreement of cooperation, being in progress