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Triamcinolone acetonide (TA) is an effective drug widely (off-label) used in the treatment of several ocular diseases involving inflammation and angiogenic processes. However, the use of TA ocular presents some limitations mainly related to its excipient composition, as in the case of benzyl alcohol. Thus, the aim of this work was to obtain an alternative TA formulation based on lipid nanocapsules (LNCs). Triamcinolone acetonide-loaded lipid nanocapsules (TA-LNCs) were obtained by the phase inversion temperature process without the use of irritating excipients, by combining lipids and surfactants generally recognized as safe. Pre-formulation studies were carried out to evaluate the TA solubility in different co-surfactants and to optimize the lipid core composition in order to enhance the drug loading and encapsulation rate in the LNCs. A stable final TA-LNC formulation was obtained with a mean particle size (MPS) of below 50 nm, a narrow size distribution (PDI < 0.2), a negative zeta potential (ZP) and a high encapsulation efficiency (%EE > 98%). In vitro cellular viability assays revealed that blank LNCs and TA-LNCs at 0.1 µg/mL did not affect the viability of the human corneal epithelial (HCE) cells. TA-LNCs showed a high anti-inflammatory activity below the toxicity level, with a reduction of 30% in interleukin (IL)-6 secretion observed in an in vitro model using the same cell line. More importantly, the TA-LNCs revealed a therapeutic efficacy in the endotoxin-induced uveitis (EIU) rabbit model with a significant attenuation of clinical signs of an inflammatory response. These findings make the TA-LNCs a safer and more efficient alternative for the treatment of eye disorders., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Oxaliplatin loaded PLAGA microspheres have been prepared by solvent extraction process. Parameters affecting the release kinetics in vitro have been studied in order to design specific release profiles suitable for direct intra-tumoral injection. By varying the nature and the relative proportions of different polymers we managed to prepare microspheres with good encapsulation efficiency (75-90%) and four different release profiles: zero order kinetics (type II) and the classical sigmoïd release profile with three different sizes of plateau and burst. These results, if correlated with in vivo activity, are promising to enhance effectiveness of local tumor treatment.

Solvent-free microparticles, loaded with a model protein (bovine serum albumin: BSA) have been produced using a novel coating process based on supercritical (SC) fluid technology. Coating material consists of either trimyristin (Dynasan114) or Gelucire50-02, two lipidic compounds having a high melting point. Microparticles were characterized as regards their morphology, protein content and in vitro release profile. A discontinuous coating made of crystalline micro-needles was obtained using Dynasan114. It led to particles with an initial burst release of about 70% in 30 min at 37 degrees C. However, a prolonged release of the protein has been achieved over a 24 h period from particles coated with Gelucire50-02, which produces a more homogeneous, film-forming coating. Furthermore, it was shown that BSA does not undergo any degradation after SCCO2 treatment under the SC conditions used in the coating process.

The two major objectives of this study were: (i) to monitor the effect of different gamma-irradiation doses (4-33 kGy) on the release kinetics from 5-fluorouracil (5-FU)-loaded poly(D,L-lactide-co-glycolide) (PLGA)-based microparticles, and (ii) to analyze the obtained experimental data with a new mathematical model giving insight into the occurring mass transport phenomena. Drug release was found to depend significantly on the applied gamma-irradiation dose. Interestingly, the obtained release profiles were all biphasic: a rapid initial drug release phase ("burst") was followed by a slower, approximately constant drug release phase. Surprisingly, only the initial rapid drug release was accelerated by gamma-irradiation; the subsequent zero-order phase was almost unaffected. Importantly, the new mathematical model which is based on Fick's second law of diffusion and which considers polymer degradation was applicable to all the investigated systems. In addition, the gamma-irradiation dose could be quantitatively related to the resulting drug release rate. In conclusion, diffusion seems to be the dominating release rate controlling mechanism in all cases, with a significant contribution of the polymer degradation process.

This paper describes the preparation of colloidal lipid particles containing magnetite from warm emulsions. A two step method was used to obtain the nanoparticles: (i) formulation of a transparent phase by heating a O/W emulsion (aqueous surfactant solution melted with a lipid phase, containing the ethyl oleate and soybean lecithin) in which modified lipophilic magnetite is incorporated, and (ii) preparation of the nanoparticles by dispersing the warm transparent phase in cold water (7 degrees C) under mechanical stirring. The latter method gives spherical nanoparticles of a mean size of 62 nm measured by Photon Correlation Spectroscopy and Transmission Electronic Microscopy. The magnetite entrapment efficiency was determined by use of a magnetophoretic sedimentation method.